Difference between revisions of "3 (number)" - New World Encyclopedia

From New World Encyclopedia
 
(43 intermediate revisions by 5 users not shown)
Line 1: Line 1:
 +
{{Images OK}}{{Approved}}{{copyedited}}
 
:''This article is about the number three.''
 
:''This article is about the number three.''
  
Line 45: Line 46:
 
|-
 
|-
 
| [[numerical prefix|prefix]]es
 
| [[numerical prefix|prefix]]es
| [[Wiktionary:tri-|tri-]] (from [[Greek language|Greek]])
+
| tri- (from [[Greek language|Greek]])
[[Wiktionary:tre-|tre-]]/[[Wiktionary:ter-|ter-]] (from [[Latin]])
+
tre-/ter- (from [[Latin]])
 
|-
 
|-
 
| [[Binary numeral system|Binary]]
 
| [[Binary numeral system|Binary]]
Line 61: Line 62:
 
|}
 
|}
  
[[Image:Three.png|thumb|right]]
+
'''3''' '''(three)''' is a [[number]], [[numeral]], and [[glyph]] that represents the number. It is the [[natural number]]<ref>A natural number is any number that is a positive integer, such as 1, 2, 3, 4, and so forth. Often, the number 0 is also called a natural number.</ref> that follows [[2 (number)|2]] and precedes [[4 (number)|4]]. It is an [[integer]] and a [[cardinal number]], that is, a number that is used for counting.<ref>A cardinal number indicates the quantity of things, but not the order in which they occur. By contrast, ordinal numbers are first, second, third, and so on, indicating their positions in a series.</ref> In addition, it is classified as a [[real number]],<ref>A real number is a number that can be given by a finite or infinite decimal representation. The term "real number" was coined to distinguish it from an "imaginary number." The set of real numbers includes rational and irrational numbers, which can be positive, negative, or zero.</ref> distinguishing it from [[imaginary number]]s.
'''3''' ('''three''') is a [[number]], [[Numeral system|numeral]], and [[glyph]]. It is the [[natural number]] following [[2 (number)|2]] and preceding [[4 (number)|4]].  
+
{{toc}}
 +
==Evolution of the glyph==
 +
The number three was once written with as many lines as the number represents. The [[Ancient Rome|Romans]] tired of writing 4 as IIII, but 3 continues to be written as three lines in Roman and [[Chinese numerals]]. This was the way the [[Brahmin]] Indians wrote it, and the [[Gupta Empire|Gupta]] made the three lines more curved. The [[Nagari]] started rotating the lines clockwise, ending each line with a slight downward stroke on the right. Eventually, they made these strokes connect with the lines below, transforming it to a character that looks very much like a modern 3 with an extra stroke at the bottom.
 +
 
 +
[[Image:Evolution3glyph.png|400px|left]]
 +
The Western Ghubar [[Arab]]s finally eliminated the extra stroke and created our modern 3. The extra stroke, however, was very important to the Eastern Arabs, who made it much larger, while rotating the strokes above to lie along a horizontal axis. To this day, Eastern Arabs write a 3 that looks like a mirrored 7 with ridges on its top line:
 +
<font style="font-size:200%;">٣</font><ref>Georges Ifrah, ''The Universal History of Numbers: From Prehistory to the Invention of the Computer'' (New York: Wiley, 2000, ISBN 0471393401), 393.</ref>
 +
 
 +
While the shape of the 3 character has an [[ascender]] in most modern [[typeface]]s, in typefaces with [[text figures]] the character usually has a [[descender]], for example, in [[Image:TextFigs036.png]].
 +
In some [[French language|French]] text-figure typefaces, though, it has an ascender instead of a descender.
 +
 
 +
A common variant of the digit 3 has a flat top, similar to the character {{unicode|Ʒ}} ([[ezh]]), sometimes used to prevent people from falsifying a 3 into an 8.
  
 
==In mathematics==
 
==In mathematics==
Line 77: Line 89:
 
Three is the fourth [[Fibonacci number]] and the third that is unique. In the [[Perrin sequence]], however, 3 is both the zeroth and third [[Perrin number]]s.
 
Three is the fourth [[Fibonacci number]] and the third that is unique. In the [[Perrin sequence]], however, 3 is both the zeroth and third [[Perrin number]]s.
  
[[Vulgar fraction]]s with 3 in the [[denominator]] have a single [[numerical digit|digit]] repeating sequences in their [[decimal]] expansions, (.000..., .333..., .666...)
+
[[Vulgar fraction]]s with 3 in the [[denominator]] have a single [[numerical digit|digit]] repeating sequences in their [[decimal]] expansions, (.000…, .333…, .666…)
  
A [[natural number]] is [[divisible]] by three if the sum of its digits in base 10 is divisible by 3. For example, the number 21 is divisible by three (3 times 7) and the sum of its digits is 2 + 1 = 3. Because of this, the reverse of any number that is divisible by three (or indeed, any [[permutation]] of its digits) is also divisible by three. For instance, 1368 and its reverse 8631 are both divisible by three (and so are 1386, 3168, 3186, 3618, etc..). See also [[Divisibility rule]].
+
A [[natural number]] is [[divisible]] by three if the sum of its digits in base 10 is divisible by 3. For example, the number 21 is divisible by three (3 times 7) and the sum of its digits is 2 + 1 = 3. Because of this, the reverse of any number that is divisible by three (or indeed, any [[permutation]] of its digits) is also divisible by three. For instance, 1368 and its reverse 8631 are both divisible by three (and so are 1386, 3168, 3186, 3618, and so on).
  
 
A [[triangle]] is the most durable shape possible, the only "perfect" figure that, if all endpoints have hinges, will never change its shape unless the sides themselves are bent.
 
A [[triangle]] is the most durable shape possible, the only "perfect" figure that, if all endpoints have hinges, will never change its shape unless the sides themselves are bent.
Line 92: Line 104:
  
 
===In numeral systems===
 
===In numeral systems===
It is frequently noted by historians of numbers that early counting systems often  
+
It is frequently noted by historians of numbers that early counting systems often relied on the three-patterned concept of "One- Two- Many" to describe counting limits. In other words, in their own language equivalent way, early peoples had a word to describe the quantities of one and two, but any quantity beyond this point was simply denoted as "Many." As an extension to this insight, it can also be noted that early counting systems appear to have had limits at the numerals 2, 3, and 4. References to counting limits beyond these three indices do not appear to prevail as consistently  
relied on the three-patterned concept of "One- Two- Many" to describe counting limits.  
 
In other words, in their own language equivalent way, early peoples had a word to  
 
describe the quantities of one and two, but any quantity beyond this point was  
 
simply denoted as "Many." As an extension to this insight, it can also be noted that  
 
early counting systems appear to have had limits at the numerals 2, 3, and 4. References  
 
to counting limits beyond these three indices do not appear to prevail as consistently  
 
 
in the historical record.
 
in the historical record.
 
 
{| class=wikitable
 
{| class=wikitable
 
|-
 
|-
Line 113: Line 118:
  
 
===List of basic calculations===
 
===List of basic calculations===
 
+
;Multiplication
 
{|class="wikitable" style="text-align: center; background: white"
 
{|class="wikitable" style="text-align: center; background: white"
 
|-
 
|-
Line 127: Line 132:
 
!9
 
!9
 
!10
 
!10
!width="5px"|
+
|-
 +
|<math>3 \times x</math>
 +
|'''3'''
 +
|[[6 (number)|6]]
 +
|[[9 (number)|9]]
 +
|[[12 (number)|12]]
 +
|[[15 (number)|15]]
 +
|[[18 (number)|18]]
 +
|[[21 (number)|21]]
 +
|[[24 (number)|24]]
 +
|[[27 (number)|27]]
 +
|[[30 (number)|30]]
 +
|}
 +
{|class="wikitable" style="text-align: center; background: white"
 +
|-
 +
!width="105px"|[[Multiplication]]
 
!11
 
!11
 
!12
 
!12
Line 138: Line 158:
 
!19
 
!19
 
!20
 
!20
!width="5px"|
 
!21
 
!22
 
!23
 
!24
 
!25
 
!width="5px"|
 
!50
 
!100
 
!1000
 
 
|-
 
|-
 
|<math>3 \times x</math>
 
|<math>3 \times x</math>
|'''3'''
 
|[[6 (number)|6]]
 
|[[9 (number)|9]]
 
|[[12 (number)|12]]
 
|[[15 (number)|15]]
 
|[[18 (number)|18]]
 
|[[21 (number)|21]]
 
|[[24 (number)|24]]
 
|[[27 (number)|27]]
 
|[[30 (number)|30]]
 
!
 
 
|[[33 (number)|33]]
 
|[[33 (number)|33]]
 
|[[36 (number)|36]]
 
|[[36 (number)|36]]
Line 171: Line 170:
 
|[[57 (number)|57]]
 
|[[57 (number)|57]]
 
|[[60 (number)|60]]
 
|[[60 (number)|60]]
!
+
|}
 +
{|class="wikitable" style="text-align: center; background: white"
 +
|-
 +
!width="105px"|[[Multiplication]]
 +
!21
 +
!22
 +
!23
 +
!24
 +
!25
 +
!width="5px"|
 +
!50
 +
!100
 +
!1000
 +
|-
 +
|<math>3 \times x</math>
 
|[[63 (number)|63]]
 
|[[63 (number)|63]]
 
|[[66 (number)|66]]
 
|[[66 (number)|66]]
Line 183: Line 196:
 
|}
 
|}
  
 +
;Division
 
{|class="wikitable" style="text-align: center; background: white"
 
{|class="wikitable" style="text-align: center; background: white"
 
|-
 
|-
Line 196: Line 210:
 
!9
 
!9
 
!10
 
!10
!width="5px"|
 
!11
 
!12
 
!13
 
!14
 
!15
 
 
|-
 
|-
 
|<math>3 \div x</math>
 
|<math>3 \div x</math>
Line 214: Line 222:
 
|<math>0.\overline{3}</math>
 
|<math>0.\overline{3}</math>
 
|0.3
 
|0.3
!
 
|<math>0.\overline{2}\overline{7}</math>
 
|0.[[25 (number)|25]]
 
|<math>0.\overline{2}3076\overline{9}</math>
 
|<math>0.2\overline{1}4285\overline{7}</math>
 
|0.2
 
 
|-
 
|-
 
|<math>x \div 3</math>
 
|<math>x \div 3</math>
Line 232: Line 234:
 
|'''3'''
 
|'''3'''
 
|<math>3.\overline{3}</math>
 
|<math>3.\overline{3}</math>
!
+
|}
 +
{|class="wikitable" style="text-align: center; background: white"
 +
|-
 +
!width="105px"|[[Division (mathematics)|Division]]
 +
!11
 +
!12
 +
!13
 +
!14
 +
!15
 +
|-
 +
|<math>3 \div x</math>
 +
|<math>0.\overline{2}\overline{7}</math>
 +
|0.[[25 (number)|25]]
 +
|<math>0.\overline{2}3076\overline{9}</math>
 +
|<math>0.2\overline{1}4285\overline{7}</math>
 +
|0.2
 +
|-
 +
|<math>x \div 3</math>
 
|<math>3.\overline{6}</math>
 
|<math>3.\overline{6}</math>
 
|4
 
|4
Line 240: Line 259:
 
|}
 
|}
  
 +
;Exponentiation
 
{|class="wikitable" style="text-align: center; background: white"
 
{|class="wikitable" style="text-align: center; background: white"
 
|-
 
|-
Line 253: Line 273:
 
!9
 
!9
 
!10
 
!10
!width="5px"|
 
!11
 
!12
 
!13
 
 
|-
 
|-
 
|<math>3 ^ x\,</math>
 
|<math>3 ^ x\,</math>
Line 269: Line 285:
 
|19683
 
|19683
 
|59049
 
|59049
!
 
|177147
 
|531441
 
|1594323
 
 
|-
 
|-
 
|<math>x ^ 3\,</math>
 
|<math>x ^ 3\,</math>
Line 285: Line 297:
 
|729
 
|729
 
|[[1000 (number)|1000]]
 
|[[1000 (number)|1000]]
!
+
|}
 +
{|class="wikitable" style="text-align: center; background: white"
 +
|-
 +
!width="105px"|[[Exponentiation]]
 +
!11
 +
!12
 +
!13
 +
|-
 +
|<math>3 ^ x\,</math>
 +
|177147
 +
|531441
 +
|1594323
 +
|-
 +
|<math>x ^ 3\,</math>
 
|1331
 
|1331
 
|1728
 
|1728
 
|2197
 
|2197
 
|}
 
|}
 
==Evolution of the glyph==
 
 
[[Image:Evolution3glyph.png]]
 
 
The number three was once written with as many lines as the number represents. The [[Ancient Rome|Romans]] tired of writing 4 as IIII, but 3 continues to be written as three lines in Roman and [[Chinese numerals]]. This was the way the [[Brahmin]] Indians wrote it, and the [[Gupta Empire|Gupta]] made the three lines more curved. The [[Nagari]] started rotating the lines clockwise, ending each line with a slight downward stroke on the right. Eventually, they made these strokes connect with the lines below, transforming it to a character that looks very much like a modern 3 with an extra stroke at the bottom.
 
 
The Western Ghubar [[Arab]]s finally eliminated the extra stroke and created our modern 3. The extra stroke, however, was very important to the Eastern Arabs, who made it much larger, while rotating the strokes above to lie along a horizontal axis. To this day, Eastern Arabs write a 3 that looks like a mirrored 7 with ridges on its top line:
 
<font style="font-size:200%;">٣</font><ref>Georges Ifrah. 1998. ''The Universal History of Numbers: From Prehistory to the Invention of the Computer''. Translated by David Bellos et al. London: The Harvill Press. p. 393, Fig. 24.63.</ref>
 
 
While the shape of the 3 character has an [[ascender]] in most modern [[typeface]]s, in typefaces with [[text figures]] the character usually has a [[descender]], for example, in [[Image:TextFigs036.png]].
 
In some [[French language|French]] text-figure typefaces, though, it has an ascender instead of a descender.
 
 
A common variant of the digit 3 has a flat top, similar to the character {{unicode|Ʒ}} ([[ezh]]), sometimes used to prevent people from falsifying a 3 into an 8.
 
  
 
==In science==
 
==In science==
 
===Astronomy===
 
===Astronomy===
 
 
* Earth is the third planet from the [[Sun]].
 
* Earth is the third planet from the [[Sun]].
* There are three types of [[galaxy|galaxies]]: elliptical, spiral, and irregular.
+
* There are three types of [[galaxy|galaxies]]: Elliptical, spiral, and irregular.
 
*[[Globular Cluster M3]] (also known as Messier Object 3 or NGC 5272) is a globular cluster in the Canes Venatici constellation.
 
*[[Globular Cluster M3]] (also known as Messier Object 3 or NGC 5272) is a globular cluster in the Canes Venatici constellation.
 
* The Roman numeral III stands for [[giant star]] in the [[stellar classification|Yerkes spectral classification scheme]].
 
* The Roman numeral III stands for [[giant star]] in the [[stellar classification|Yerkes spectral classification scheme]].
* The Roman numeral III (usually) stands for the third-discovered satellite of a planet or minor planet (e.g. [[Pluto III]])
+
* The Roman numeral III (usually) stands for the third-discovered satellite of a planet or minor planet (for example, [[Pluto III]])
 
* In the constellation [[Orion (constellation)|Orion]], the "belt" is made up of 3 stars in a row.
 
* In the constellation [[Orion (constellation)|Orion]], the "belt" is made up of 3 stars in a row.
  
 
=== Biology ===
 
=== Biology ===
 
 
;Classification of biological forms:
 
;Classification of biological forms:
 
* 3 basic life domains: Archaea, Bacteria, and Eucarya
 
* 3 basic life domains: Archaea, Bacteria, and Eucarya
Line 347: Line 356:
  
 
'''3 social group types of the Great Apes:'''
 
'''3 social group types of the Great Apes:'''
# Orangutans (Solitary - little amount of both sexes)
+
# Orangutans (Solitary--little amount of both sexes)
# Gorillas (Harems - great amount of one sex)
+
# Gorillas (Harems--great amount of one sex)
# Common Chimps (Live in territories defended by related males - great amount of both sexes)
+
# Common Chimps (Live in territories defended by related males--great amount of both sexes)
  
 
'''Three traditional families of hominoid:'''
 
'''Three traditional families of hominoid:'''
# Hylobatidae: include the so-called lesser apes of Asia, the gibbons and siamangs.
+
# Hylobatidae: Include the so-called lesser apes of Asia, the gibbons and siamangs.
# Hominidae: include living humans and typically fossil apes that possess a suite of characteristics such as bipedalism, reduced canine size, and increasing brain size such as the australopithecines.
+
# Hominidae: Include living humans and typically fossil apes that possess a suite of characteristics such as bipedalism, reduced canine size, and increasing brain size such as the australopithecines.
# Pongidae: include the remaining African great apes including gorillas, chimpanzees, and the Asian orangutan.
+
# Pongidae: Include the remaining African great apes including gorillas, chimpanzees, and the Asian orangutan.
  
 
;Molecular biology
 
;Molecular biology
Line 364: Line 373:
  
 
;Physiology
 
;Physiology
* 3 distinct Cytoskeleton components: Microtubules~ Intermediate Filament~ Actin Filaments
+
* 3 distinct Cytoskeleton components: Microtubules, Intermediate Filament, Actin Filaments
* 3 primary cellular energy molecules: AMP~ ADP~ ATP
+
* 3 primary cellular energy molecules: AMP, ADP, ATP
* 3 main fatty acid categories: Saturated~ Monounsaturated~ Polyunsaturated
+
* 3 main fatty acid categories: Saturated, Monounsaturated, Polyunsaturated
* 3 substances metabolized for energy needs: Carbohydrates~ Fats~ Proteins
+
* 3 substances metabolized for energy needs: Carbohydrates, Fats, Proteins
 
* Triglycerides are the main storage forms of fatty acids.
 
* Triglycerides are the main storage forms of fatty acids.
 
* 3 primary germ layers of a mammalian [[embryo]]: Endoderm, Mesoderm, Ectoderm.
 
* 3 primary germ layers of a mammalian [[embryo]]: Endoderm, Mesoderm, Ectoderm.
  
 
;Plants and Animals
 
;Plants and Animals
* Triceratops: Cretaceous period dinosaur with three horns on its head.
+
* [[Triceratops]]: [[Cretaceous]] period dinosaur with three horns on its head.
 
* Shamrock: refers to one of several trifoliate (three-leaved) plants of the Leguminosae family which includes the clover.
 
* Shamrock: refers to one of several trifoliate (three-leaved) plants of the Leguminosae family which includes the clover.
* 3-bodied general description of insects: Head~ Thorax~ Abdomen.
+
* 3-bodied general description of insects: Head, Thorax, Abdomen.
 
* Trilobite: hard-bodied invertebrate marine arthropod of the Paleozoic era with three lobes.
 
* Trilobite: hard-bodied invertebrate marine arthropod of the Paleozoic era with three lobes.
* Monocotyledon: A monocot's flower is often trimerous, with the flower parts in threes or in multiples of three (typically three, six, or nine petals.)
+
* Monocotyledon: A monocot's flower is often trimerous, with the flower parts in threes or in multiples of three (typically three, six, or nine petals).
  
 
===Chemistry===
 
===Chemistry===
 
 
* Three is the [[atomic number]] of [[lithium]].
 
* Three is the [[atomic number]] of [[lithium]].
* [[Atoms]] consist of three types of constituents: [[protons]], [[neutrons]], and [[electrons]].
+
* [[Atoms]] consist of three types of constituents: [[Protons]], [[neutrons]], and [[electrons]].
 
* 3 types of molecular bonds: Covalent, Ionic, and Polar Covalent (Dative or Coordinate).
 
* 3 types of molecular bonds: Covalent, Ionic, and Polar Covalent (Dative or Coordinate).
 
* 3 types of isomerism: Structural (Ethyl alcohol), Geometric (Maleic acid), and Optical (L-Lactic acid).
 
* 3 types of isomerism: Structural (Ethyl alcohol), Geometric (Maleic acid), and Optical (L-Lactic acid).
Line 394: Line 402:
  
 
===Physics===
 
===Physics===
 +
* Humans perceive the [[universe]] to have three spatial [[dimension]]s.
  
* We perceive our [[universe]] to have three spatial [[dimension]]s.
+
* White light is composed of a mixture of the three additive [[primary color|primary hues]]: Red, green, and blue.
 
 
* White light is composed of a mixture of the three additive [[primary color|primary hues]]: red, green, and blue.
 
  
 
;Particle physics:
 
;Particle physics:
 
* There are three generations of fundamental [[lepton]]s ([[electron]], [[muon]], [[tauon]] and their [[neutrino]]s) and three groups of flavors of [[quark]]s (up-down, charmed-strange, top-bottom).
 
* There are three generations of fundamental [[lepton]]s ([[electron]], [[muon]], [[tauon]] and their [[neutrino]]s) and three groups of flavors of [[quark]]s (up-down, charmed-strange, top-bottom).
* A neutron consists of three quarks: two down quarks and one up quark.
+
* A neutron consists of three quarks: Two down quarks and one up quark.
  
 
* Nature defines the state of supersymmetry as ±0 (left- and right-handed). This allows additional variations with respect to the breaking of supersymmetry involving the number three. The whole spectrum of possibilities based on the number three thus is duplicated for matter and antimatter.
 
* Nature defines the state of supersymmetry as ±0 (left- and right-handed). This allows additional variations with respect to the breaking of supersymmetry involving the number three. The whole spectrum of possibilities based on the number three thus is duplicated for matter and antimatter.
Line 411: Line 418:
 
* Three non-gravitational forces actively are generated by three different superstring spin functionalities, while gravity is a passive reaction of spacetime due to the presence of superstrings with broken supersymmetry.
 
* Three non-gravitational forces actively are generated by three different superstring spin functionalities, while gravity is a passive reaction of spacetime due to the presence of superstrings with broken supersymmetry.
  
*Three represents an optimum of economy in a physical geometrical realization and a maximum of functionality at the same time. This limits the otherwise nearly infinite number of degrees of freedom by a defined geometry with a specific functionality to exactly the ones needed to generate the fundamental basis for the expression of the 'Everything'.  
+
*Three represents an optimum of economy in a physical geometrical realization and a maximum of functionality at the same time. This limits the otherwise nearly infinite number of degrees of freedom by a defined geometry with a specific functionality to exactly the ones needed to generate the fundamental basis for the expression of the "Everything."
  
 
*The number three is shown to be represented by different possible spin states in the regime from -3 to +3, that is by negative and positive integer numbers, including a -0 and +0, in contrast to mathematics where 0 is an integer number without sign. Due to geometrically defined quanta of spin, the superstring shows a physical realization of integer numbers between -3 and +3. This answers Roger Penrose's question of the physical meaning of integer numbers (Road to Reality, p. 65) and their relevance in the physical world.
 
*The number three is shown to be represented by different possible spin states in the regime from -3 to +3, that is by negative and positive integer numbers, including a -0 and +0, in contrast to mathematics where 0 is an integer number without sign. Due to geometrically defined quanta of spin, the superstring shows a physical realization of integer numbers between -3 and +3. This answers Roger Penrose's question of the physical meaning of integer numbers (Road to Reality, p. 65) and their relevance in the physical world.
Line 418: Line 425:
  
 
* Three is the smallest number that, in a physical realization, on breaking of symmetry allows the emergence of two additional functionalities different from the one of a central state. These either can be symmetric as in -3 (±0) +3 (electron, two supersymmetric superstrings (left/right-handed, no matter particles, dark), and the positron) or asymmetric as in -1 (-0) +2 (quarks) or -2 (+0) +1 (anti quarks). This means, breaking of a symmetry also can result in one of two different asymmetric states. In this case supersymmetry globally is conserved on the average by the properties of three quarks (enforced quark confinement). Multiplication of these angular spins by 1/3 gives the three particle charges, negative or positive are defined by the direction of angular spin.
 
* Three is the smallest number that, in a physical realization, on breaking of symmetry allows the emergence of two additional functionalities different from the one of a central state. These either can be symmetric as in -3 (±0) +3 (electron, two supersymmetric superstrings (left/right-handed, no matter particles, dark), and the positron) or asymmetric as in -1 (-0) +2 (quarks) or -2 (+0) +1 (anti quarks). This means, breaking of a symmetry also can result in one of two different asymmetric states. In this case supersymmetry globally is conserved on the average by the properties of three quarks (enforced quark confinement). Multiplication of these angular spins by 1/3 gives the three particle charges, negative or positive are defined by the direction of angular spin.
 +
 +
==In technology==
 +
[[Image:U+2675 DejaVu Sans.svg|120px|right|3 as a resin identification code, used in recycling.]]
 +
 +
* Three is the [[resin identification code]] used in recycling to identify [[polyvinyl chloride]].
 +
* In [[ASCII]], the code for "3" in hexadecimal is 33. This is the only character in ASCII such that a large file consisting of a single character has identical-looking hexadecimal and normal representation.
 +
 +
[[Image:Seven-segment 3.svg|120px|right]]
 +
 +
* Three is approximately [[pi]] (which is closer to 3.14159) when doing rapid engineering wags or estimates. The same is true if one wants a rough-and-ready estimate of [[E (mathematical constant)|''e'']], which is approximately 2.7183.
 +
* Some [[computer]] users may use "3" as an alternate to the letter "[[E]]," often in jest or to prevent search engines from reading their messages. This form of code is an example of basic [[Leetspeak]].
 +
* "3" is the [[DVD region code]] for many East Asian countries, except for Japan (which is Region 2) and China (which is Region 6).
 +
* The glyph "3" may be used as a substitute for [[yogh]] ({{unicode|Ȝ, ȝ}}) or [[Ze (Cyrillic)|ze]] ({{unicode|З, з}}) when those characters are not available.
 +
* Three is the minimum odd number of voting components for simple easy [[redundancy checks]] by direct comparison.
  
 
==In history==
 
==In history==
Line 425: Line 446:
 
* 3rd Estate: French Revolution
 
* 3rd Estate: French Revolution
 
* 3rd Way: Mussolini's social movement
 
* 3rd Way: Mussolini's social movement
* 3rd Wave: journalistic name given to Newt Gingrich's social movement (U.S.)
+
* 3rd Wave: Journalistic name given to Newt Gingrich's social movement (U.S.)
* Third Communist International was founded in 1919 by Vladimir Ilyich Lenin (He died after a 3rd stroke).
+
* Third Communist International was founded in 1919 by [[Vladimir Ilyich Lenin]] (He died after a 3rd stroke).
  
 
==In religion==
 
==In religion==
  
 
===Abrahamic religions===
 
===Abrahamic religions===
[[Image:Shield-Trinity-Scutum-Fidei-English.png|thumb|The [[Shield of the Trinity]] is a diagram of the Christian doctrine of the Trinity.]]
+
[[Image:Shield-Trinity-Scutum-Fidei-English.png|thumb|350px|The [[Shield of the Trinity]] is a diagram of the Christian doctrine of the Trinity.]]
 +
 
 
* There are three main [[Abrahamic religion]]s: [[Judaism]], [[Christianity]], and [[Islam]].
 
* There are three main [[Abrahamic religion]]s: [[Judaism]], [[Christianity]], and [[Islam]].
 
* [[Noah]] had three sons: [[Shem]], [[Ham]] and [[Japheth]].
 
* [[Noah]] had three sons: [[Shem]], [[Ham]] and [[Japheth]].
  
 
===Christianity===
 
===Christianity===
 
+
* In the Christian concept of the [[Trinity|Holy Trinity]], God is a single being with three persons: The Father, Son and Holy Spirit.
* In the Christian concept of the [[Trinity|Holy Trinity]], God is a single being with three persons: the Father, Son and Holy Spirit.
 
 
* Three [[Biblical Magi|Wise Men]] visited Jesus after his birth and brought him three gifts.
 
* Three [[Biblical Magi|Wise Men]] visited Jesus after his birth and brought him three gifts.
 
* Jesus had three main disciples.
 
* Jesus had three main disciples.
Line 443: Line 464:
 
* Jesus rose from the dead on the third day after his death.
 
* Jesus rose from the dead on the third day after his death.
 
* Jesus predicted that Peter would deny him three times.
 
* Jesus predicted that Peter would deny him three times.
* Three [[theological virtues]] are mentioned in [[1 Corinthians 13]].
+
* [[St. Paul|Paul]]'s first letter to the Corinthians (1 Cor 13:13) mentions three [[theological virtues]]: faith, hope, and love.
 
* In [[Roman Catholicism]], there are three groups of [[martyrs]], collectively known as [[Faith, Hope, and Charity]] (named after the Theological Virtues).
 
* In [[Roman Catholicism]], there are three groups of [[martyrs]], collectively known as [[Faith, Hope, and Charity]] (named after the Theological Virtues).
 
* Catholicism also mentions three divisions in the spiritual world: [[Heaven]], [[Hell]], and [[Purgatory]] (or Limbo).
 
* Catholicism also mentions three divisions in the spiritual world: [[Heaven]], [[Hell]], and [[Purgatory]] (or Limbo).
 
=== Islam ===
 
 
* In [[Muslim]] devotional rites, certain formulas are repeated three times, and others, thirty-three times.
 
* A devout Muslim tries to make a [[pilgrimage]] to all three holy cities of Islam: [[Mecca]], [[Medina]], and [[Jerusalem]].
 
  
 
=== Judaism ===
 
=== Judaism ===
Line 460: Line 476:
 
* There are 3 daily [[Jewish services|prayer services]]: ''Shacharit'', ''Mincha'', and ''Maariv''
 
* There are 3 daily [[Jewish services|prayer services]]: ''Shacharit'', ''Mincha'', and ''Maariv''
 
* [[Shimon Hatzaddik]] taught: "On three things the world stands: On [[Torah]], on prayer, and on acts of kindness" ([[Pirkei Avoth]] 1:2). Rabban [[Shimon ben Gamliel]] taught: "The world continues to exist because of three things: justice, truth, and peace" (ibid. 1:18).
 
* [[Shimon Hatzaddik]] taught: "On three things the world stands: On [[Torah]], on prayer, and on acts of kindness" ([[Pirkei Avoth]] 1:2). Rabban [[Shimon ben Gamliel]] taught: "The world continues to exist because of three things: justice, truth, and peace" (ibid. 1:18).
 +
 +
=== Islam ===
 +
* In [[Muslim]] devotional rites, certain formulas are repeated three times, and others, thirty-three times.
 +
* A devout Muslim tries to make a [[pilgrimage]] to all three holy cities of Islam: [[Mecca]], [[Medina]], and [[Jerusalem]].
  
 
=== Zoroastrianism ===
 
=== Zoroastrianism ===
 
 
* In their daily prayers, Zoroastrians commit themselves to pursuing three types of goodness: good thoughts, good words, and good deeds.
 
* In their daily prayers, Zoroastrians commit themselves to pursuing three types of goodness: good thoughts, good words, and good deeds.
* At the same time, they pray to reject three types of evil: evil thoughts, evil words, and evil deeds.
+
* At the same time, they pray to reject three types of evil: Evil thoughts, evil words, and evil deeds.
  
 
=== Hinduism ===
 
=== Hinduism ===
Line 474: Line 493:
  
 
===In Buddhism===
 
===In Buddhism===
*The Triple Gem - [[Gautama Buddha|Buddha]], [[Dharma (Buddhism)|Dhamma]] (Buddha's teaching) and [[Sangha]] (the preachers of Dhamma).
+
*The Triple Gem--[[Gautama Buddha|Buddha]], [[Dharma (Buddhism)|Dhamma]] (Buddha's teaching) and [[Sangha]] (the preachers of Dhamma).
*The Triple Bodhi (ways to understand the end of birth)- Budhu, Pasebudhu, Mahaarahath
+
*The Triple Bodhi (ways to understand the end of birth)--Budhu, Pasebudhu, Mahaarahath
* Buddhism's three refuges are called "Trisharana": Buddhan sharanam gacchami, Dhammam sharanam gacchami, Sangham sharanam gacchami.
+
*Buddhism's three refuges are called "Trisharana:" Buddhan sharanam gacchami, Dhammam sharanam gacchami, Sangham sharanam gacchami.
  
 
===Other religions===
 
===Other religions===
*The [[Wicca]]ns have a [[Rule of Three (Wiccan)|Rule of Three]].
+
*[[Wicca]]ns have a [[Rule of Three (Wiccan)|Rule of Three]].
*The [[Triple Goddess]]: Maiden, Mother, Crone; the three fates.
+
*[[Taoism]] teaches about the [[Three Pure Ones]].
* [[Taoism]] teaches about the [[Three Pure Ones]].
 
  
 
==In mythology==
 
==In mythology==
 
 
* 3 Greek gods: Zeus, Poseidon, Hades (Air, Water, Earth)
 
* 3 Greek gods: Zeus, Poseidon, Hades (Air, Water, Earth)
 
* 3 Roman gods: Jupiter, Neptune, Pluto (Air, Water, Earth)
 
* 3 Roman gods: Jupiter, Neptune, Pluto (Air, Water, Earth)
Line 490: Line 507:
 
* Ancient Egypt Theban Triad: Amun, Mut, and their son Khans.
 
* Ancient Egypt Theban Triad: Amun, Mut, and their son Khans.
 
* 3 ancient Egyptian central religious figures: Horus, Isis, Osiris.
 
* 3 ancient Egyptian central religious figures: Horus, Isis, Osiris.
*  The Maya believed 3 stars in the Orion Constellation (Alnitak, Saiph, Rigel) were arranged by the gods as a triangular hearth, enclosing the smoke of the fire creation - the nebula.
+
*  The Maya believed 3 stars in the Orion Constellation (Alnitak, Saiph, Rigel) were arranged by the gods as a triangular hearth, enclosing the smoke of the fire creation--the nebula.
 
* 3 Greek Fates (Moirai, Moirés): [[Clotho]], [[Lachesis (mythology)|Lachesis]], [[Atropos]] (sometimes referred to as the 3 spinners).
 
* 3 Greek Fates (Moirai, Moirés): [[Clotho]], [[Lachesis (mythology)|Lachesis]], [[Atropos]] (sometimes referred to as the 3 spinners).
 
* 3 Roman Fates: Decima, Nona (goddesses of birth), Morta (goddess of death)
 
* 3 Roman Fates: Decima, Nona (goddesses of birth), Morta (goddess of death)
Line 499: Line 516:
 
* 3 different beings made up the different qualities of death according to ancient Greek belief: Thantos (male), Ker (female), Gorgo (female).
 
* 3 different beings made up the different qualities of death according to ancient Greek belief: Thantos (male), Ker (female), Gorgo (female).
 
* 3 Roman Furies (female personifications of vengeance) that were called the Erinyes (the Angry Ones) or Eumenides by the Ancient Greeks (Orestes called them the Solemn Ones, or the Kindly Ones): Alecto ("unceasing"), Megaera ("grudging"), Tisiphone ("avenging murder").
 
* 3 Roman Furies (female personifications of vengeance) that were called the Erinyes (the Angry Ones) or Eumenides by the Ancient Greeks (Orestes called them the Solemn Ones, or the Kindly Ones): Alecto ("unceasing"), Megaera ("grudging"), Tisiphone ("avenging murder").
* 3-headed dog that guarded the gate to Hades in Greek Mythology: Cerberus
+
* 3-headed dog that guarded the gate to Hades in Greek Mythology: [[Cerberus]]
 
* 3 ancient Greek Harpies: Aello, Ocypete, and Celaeno.
 
* 3 ancient Greek Harpies: Aello, Ocypete, and Celaeno.
  
 
==In philosophy==
 
==In philosophy==
 
 
{|class="wikitable" width="100%" bgColor="#ffffff" border="1" borderColor="#e6e6e6"  
 
{|class="wikitable" width="100%" bgColor="#ffffff" border="1" borderColor="#e6e6e6"  
 
     |+'''3-patterned Philosophical Distinctions'''
 
     |+'''3-patterned Philosophical Distinctions'''
 
     |-  
 
     |-  
     | St. Augustine's Philosophy: || Memory~ Understanding~ Will
+
     | [[St. Augustine]]'s Philosophy: || Memory~ Understanding~ Will
 
     |-
 
     |-
     | Aquinas's 3 transcendentals of being: || Unity~ Truth~ Goodness
+
     | [[Aquinas]]' 3 transcendentals of being: || Unity~ Truth~ Goodness
 
     |-
 
     |-
     | Aquinas's 3 requisites for the beautiful: || Wholeness or perfection~ Harmony or due proportion~ Radiance
+
     | Aquinas' 3 requisites for the beautiful: || Wholeness or perfection~ Harmony or due proportion~ Radiance
 
     |-
 
     |-
     | Aquinas's 3 logical faculties (based in Aristotle) || Conception~ Judgment~ Reasoning  
+
     | Aquinas' 3 logical faculties (based in Aristotle) || Conception~ Judgment~ Reasoning  
 
     |-
 
     |-
     | Aquinas's 3 causal principles (based in Aristotle) || Agent~ Patient~ Act
+
     | Aquinas' 3 causal principles (based in Aristotle) || Agent~ Patient~ Act
 
     |-
 
     |-
     | Comte's Philosophy: || Great Being~ Great Medium~ Great Fetish
+
     | [[Auguste Comte|Comte]]'s Philosophy: || Great Being~ Great Medium~ Great Fetish
 
     |-
 
     |-
     | Hegel's 3 Spirits: || Subjective Spirit~ Objective Spirit~ Absolute Spirit
+
     | [[Hegel]]'s 3 Spirits: || Subjective Spirit~ Objective Spirit~ Absolute Spirit
 
     |-
 
     |-
     | Plotinu's Philosophy: || One~ One Many~ One and Many
+
     | [[Plotinus]]' Philosophy: || One~ One Many~ One and Many
 
     |-
 
     |-
     | Aristotle's 3 Unities: || Unity of Action~ Unity of Time~ Unity of Place
+
     | [[Aristotle]]'s 3 Unities: || Unity of Action~ Unity of Time~ Unity of Place
 
     |-
 
     |-
     | Sir F. Bacon's 3 Tables: || Presence~ Absence~ Degree  
+
     | [[Francis Bacon]]'s 3 Tables: || Presence~ Absence~ Degree  
 
     |-
 
     |-
     | Thomas Hobbes's 3 Fields: || Physics~ Moral Philosophy~ Civil Philosophy
+
     | [[Thomas Hobbes]]' 3 Fields: || Physics~ Moral Philosophy~ Civil Philosophy
 
     |-
 
     |-
     | Immanuel Kant's 3 Critiques: || Pure Reason~ Practical Reason~ Judgment
+
     | [[Immanuel Kant]]'s 3 Critiques: || Pure Reason~ Practical Reason~ Judgment
 
     |-
 
     |-
     | Averroes's 3 Commentaries: || Little~ Middle~ Great
+
     | [[Averroes]]' 3 Commentaries: || Little~ Middle~ Great
 
     |-
 
     |-
     | Karl Marx's 3 isms: || Communism~ Socialism~ Capitalism
+
     | [[Karl Marx]]'s 3 isms: || Communism~ Socialism~ Capitalism
 
     |-
 
     |-
     | Woodrow Wilson's 3 isms: || Colonialism~ Racism~ Anti-Communism
+
     | [[Woodrow Wilson]]'s 3 isms: || Colonialism~ Racism~ Anti-Communism
 
     |-
 
     |-
     | Hippocrates's Mind Disorders: || Mania~ Melancholia~ Phrenitis  
+
     | [[Hippocrates]]' Mind Disorders: || Mania~ Melancholia~ Phrenitis  
 
     |-
 
     |-
     | Emile Durkeim's 3 Suicides: || Egoistic~ Altruistic~ Anomic
+
     | [[Emile Durkheim]]'s 3 Suicides: || Egoistic~ Altruistic~ Anomic
 
     |-  
 
     |-  
     | D. Liesman's 3 Social Characters: || Tradition-directed~ Inner-directed~ Other-directed
+
     | [[David Riesman]]'s 3 Social Characters: || Tradition-directed~ Inner-directed~ Other-directed
 
     |-  
 
     |-  
     | Erich Fromm's 3 Symbols: || The Conventional~ The Accidental~ The Universal
+
     | [[Erich Fromm]]'s 3 Symbols: || The Conventional~ The Accidental~ The Universal
 
     |-
 
     |-
     | Pythagoras's "fusion" idea: || Monarchy~ Oligarchy~ Democracy (into harmonic whole)
+
     | [[Pythagoras]]' "fusion" idea: || Monarchy~ Oligarchy~ Democracy (into harmonic whole)
 
     |-
 
     |-
     | M.L. King Jr.'s "Middle Road": || Acquiescence~ Nonviolence~ Violence  
+
     | [[Martin Luther King Jr.]]'s "Middle Road": || Acquiescence~ Nonviolence~ Violence  
 
     |-  
 
     |-  
     | Kierkegaard's 3 Stages: || Aesthetic~ Ethical~ Religious
+
     | [[Kierkegaard]]'s 3 Stages: || Aesthetic~ Ethical~ Religious
 
     |-
 
     |-
     | Husserl's 3 Reductions: || Phenomenological~ Eidetic~ Religious
+
     | [[Husserl]]'s 3 Reductions: || Phenomenological~ Eidetic~ Religious
 
     |-  
 
     |-  
 
     | St. Augustine's 3 Laws: || Divine Law~ Natural Law~ Temporal, or positive Law  
 
     | St. Augustine's 3 Laws: || Divine Law~ Natural Law~ Temporal, or positive Law  
Line 557: Line 573:
 
     | Witness Stand truths: || The Truth~ The whole Truth~ Nothing but the Truth
 
     | Witness Stand truths: || The Truth~ The whole Truth~ Nothing but the Truth
 
     |-  
 
     |-  
     | Titus Carus's 3 Ages: || Stone Age~ Bronze Age~ Iron Age  
+
     | [[Lucretius]]' 3 Ages: || Stone Age~ Bronze Age~ Iron Age  
 
     |-  
 
     |-  
     | Feuerbach's 3 Thoughts: || God, 1st Thought~ Reason, 2nd~ Man, 3rd
+
     | [[Feuerbach]]'s 3 Thoughts: || God, 1st Thought~ Reason, 2nd~ Man, 3rd
 
     |-
 
     |-
     | Magnus's 3 Universals: || Ante Rem~ In Rem~ Post Rem
+
     | [[Albertus Magnus]]' 3 Universals: || Ante Rem~ In Rem~ Post Rem
 
     |-
 
     |-
     | Max Weber's 3 Authorities: || Traditional~ Charismatic~ Legal-rational
+
     | [[Max Weber]]'s 3 Authorities: || Traditional~ Charismatic~ Legal-rational
 
     |-
 
     |-
     | F.&nbsp; de Sausure's 3 "Signs": || Sign~ Signified~ Signifier  
+
     | [[Ferdinand de Saussure]]'s 3 "Signs": || Sign~ Signified~ Signifier  
 
     |-
 
     |-
     | Charles Peirce's 3 semiotic elements || Sign~ Object~ Interpretant  
+
     | [[Charles Peirce]]'s 3 semiotic elements || Sign~ Object~ Interpretant  
 
     |-
 
     |-
 
     | Charles Pierce's 3 categories: || Quality of feeling~ Reaction/resistance~ Representation
 
     | Charles Pierce's 3 categories: || Quality of feeling~ Reaction/resistance~ Representation
Line 579: Line 595:
 
     | Charles Peirce's 3 modes of evolution: || Fortuitous variation~ Mechanical necessity~ Creative love
 
     | Charles Peirce's 3 modes of evolution: || Fortuitous variation~ Mechanical necessity~ Creative love
 
     |-
 
     |-
     | John Keynes's 3 Eras: || Scarcity~ Abundance~ Stabilization
+
     | [[John Maynard Keynes]]'s 3 Eras: || Scarcity~ Abundance~ Stabilization
 
     |-
 
     |-
     | George Mead's 3 Distinctions: || Self~ I~ Me  
+
     | [[George Mead]]'s 3 Distinctions: || Self~ I~ Me  
 
     |-  
 
     |-  
     | Thrasher's 3-group Gangs: || Inner Circle~ Rank & File~ Fringers
+
     | [[Frederic Thrasher]]'s 3-group Gangs: || Inner Circle~ Rank & File~ Fringers
 
     |-
 
     |-
     | Abe Lincoln's 3-For-All: || Of the People~ By the People~ For the People  
+
     | [[Abraham Lincoln]]'s 3-For-All: || Of the People~ By the People~ For the People  
 
     |-
 
     |-
     | Samuel Clemmons' (Mark Twain) 3 lies: || Lies~ Damned Lies~ Statistics
+
     | Samuel Clemmons' ([[Mark Twain]]) 3 lies: || Lies~ Damned Lies~ Statistics
 
     |-
 
     |-
 
     | J.W.S. Pringle's 3 intellectual problems: || Religious & Ethical~ Practical~ Scientific
 
     | J.W.S. Pringle's 3 intellectual problems: || Religious & Ethical~ Practical~ Scientific
 
     |-
 
     |-
     | J. Bruner's 3 cognitive processing modes: || Enactive~ Iconic~ Symbolic
+
     | [[Jerome Bruner]]'s 3 cognitive processing modes: || Enactive~ Iconic~ Symbolic
 
     |-
 
     |-
     | Wilhelm Wundt's 3 mind elements: || Sensations~ Images~ Feelings
+
     | [[Wilhelm Wundt]]'s 3 mind elements: || Sensations~ Images~ Feelings
 
     |-
 
     |-
     | Robert Sternberg's 3 love components: || Passion~ Intimacy~ Commitment
+
     | [[Robert Sternberg]]'s 3 love components: || Passion~ Intimacy~ Commitment
 
     |-
 
     |-
     | Sternberg's Triarchic Intelligence: || Analytic~ Creative~ Practica
+
     | Robert Sternberg's Triarchic Intelligence: || Analytic~ Creative~ Practica
 
     |-
 
     |-
     | Paul D. Maclean's Triune Brain: || R-System (Reptilian)~ Limbic System~ Neocortex
+
     | [[Paul D. Maclean]]'s Triune Brain: || R-System (Reptilian)~ Limbic System~ Neocortex
 
     |-
 
     |-
 
     | 3-monkey Philosophy: || Hear no Evil~ See no Evil~ Speak no Evil
 
     | 3-monkey Philosophy: || Hear no Evil~ See no Evil~ Speak no Evil
 
     |-
 
     |-
     | J.A. Fodor's mind Taxonomy: || Central Processes~ Input Processes~ Transducers
+
     | [[Jerry Fodor]]'s mind Taxonomy: || Central Processes~ Input Processes~ Transducers
 
     |-
 
     |-
 
     | Plato's Tripartite soul: || Rational~ Libidinous~ Spirited (various animal qualities)
 
     | Plato's Tripartite soul: || Rational~ Libidinous~ Spirited (various animal qualities)
Line 609: Line 625:
 
     | Hjalmar Wennerberg's philosophy orders: || Phenomenology~ Normative Science~ Metaphysics
 
     | Hjalmar Wennerberg's philosophy orders: || Phenomenology~ Normative Science~ Metaphysics
 
     |-
 
     |-
     | W.H. Sheldon's body types: || Endomorph~ Mesomorph~ Ectomorph
+
     | [[William Herbert Sheldon]]'s body types: || Endomorph~ Mesomorph~ Ectomorph
 
     |-
 
     |-
     | Ernst Kretschmer's body types: || Pyknic~ Asthenic~ Athletic
+
     | [[Ernst Kretschmer]]'s body types: || Pyknic~ Asthenic~ Athletic
 
     |-
 
     |-
 
     | Aristotle's 3 in 1 idea: || Mind~ Self-knowledge~ Self-love  
 
     | Aristotle's 3 in 1 idea: || Mind~ Self-knowledge~ Self-love  
 
     |-
 
     |-
     | K.J.W. Craik's 3 reasoning processes: || Translation~ Reasoning~ Retranslation
+
     | [[Kenneth Craik]]'s 3 reasoning processes: || Translation~ Reasoning~ Retranslation
 
     |-
 
     |-
     | Galton's 3 genius traits: || Intellect~ Zeal~ Power of working
+
     | [[Francis Galton]]'s 3 genius traits: || Intellect~ Zeal~ Power of working
 
     |-
 
     |-
    | Gregor Mendel "laws": || Independent Unit Characters~ Segregation~ Dominance
 
    |-
 
 
|}
 
|}
  
 
==In Education==
 
==In Education==
* 3 R's: Reading~ 'Riting~ 'Rithmetic
+
* 3 R's: Reading, 'Riting, 'Rithmetic.
* 3 divisions: Elementary (Grade) School~ Middle (Jr. High or Intermediate) School~ High (Sr. High) School
+
* 3 levels: Primary (Elementary) Education, Secondary (Jr. and Sr. High) Education, Tertiary (College, University, Polytechnical Institute, TAFE) Education.
* 3 levels: Primary (~Elementary) Education~ Secondary (~Jr. + Sr. High) Education~ Tertiary (College, University, Polytechnical Institute, TAFE) Education
+
* 3 levels of University degrees: Bachelor's, Maste, Doctor's (Ph.D., M.D., J.D., and so on)
* 3 University degrees: Bachelor's~ Master's- Ph.D
+
* 3 University distinctions at graduation: Cum Laude, Magna Cum Laude, Summa Cum Laude.
* 3 University distinctions: Cum Laude~ Magna Cum Laude~ Suma Cum Laude
+
* 3 good grade divisions: A, B, C
* 3 testing formats: True/False~ Multiple Choice~ Essay
+
* 3 levels to each grade formula: A+ (A plus), A (A neutral), A- (A minus)
* 3 levels to grade formulas: A+ (A plus)~ A (A neutral)~ A- (A minus)
 
* 3 good grade divisions: A~ B~ C
 
* 3 rings of the school bell return children to class after a fire drill.
 
* 3 ring notebooks are one standard of usage for holding looseleaf notebook paper (2 is another in lever-arch).
 
* 3-number combination locks are a standard usage for lockers.
 
  
 
==In politics==
 
==In politics==
 +
[[Image:Ständeordnung.jpg|thumb|300px|Christ sorting people into prayers, protectors and workers.]]
 
*[[Plato]] split [[Plato's Republic|his utopian city]] into three populations: laborers, guardians (warriors), and philosophers (rulers)
 
*[[Plato]] split [[Plato's Republic|his utopian city]] into three populations: laborers, guardians (warriors), and philosophers (rulers)
 
*Several polities have been ruled by three persons in a [[triumvirate]] or a [[troika (triumvirate)|troika]].
 
*Several polities have been ruled by three persons in a [[triumvirate]] or a [[troika (triumvirate)|troika]].
*As well, medieval theory divided society in ''[[laboratores]]'' (peasants), ''[[bellatores]]'' (noble warriors) and ''[[oratores]]'' ([[clergy]]). An earlier division had only the ''[[potentes]]'' ("powerful," warriors) and the powerless.
+
* Medieval theory divided society in ''[[laboratores]]'' (peasants), ''[[bellatores]]'' (noble warriors) and ''[[oratores]]'' ([[clergy]]). An earlier division had only the ''[[potentes]]'' ("powerful," warriors) and the powerless.
[[Image:Ständeordnung.jpg|thumb|Christ sorting people into prayers, protectors and workers.]]
+
*In the [[Ancient Regime]], the [[estates of the realm]] (for example, the [[French Estates General]]) were divided in a branch for [[aristocracy]], another for the Catholic hierarchy and the [[Third Estate]] for rich peasants and [[bourgeoisie]]. The triumph of the Third Estate is the [[French Revolution]].
*In the [[Ancient Regime]], the [[estates of the realm]] (e.g. the [[French Estates General]]) were divided in a branch for [[aristocracy]], another for the Catholic hierarchy and the [[Third Estate]] for rich peasants and [[bourgeoisie]]. The triumph of the Third Estate is the [[French Revolution]].
 
 
*By analogy to the Third Estate, the [[Third World]] (poor countries or [[non-aligned]] countries) was defined as different from the [[First World]] (led by the United States) and the [[Second World]] (led by the Soviet Union).
 
*By analogy to the Third Estate, the [[Third World]] (poor countries or [[non-aligned]] countries) was defined as different from the [[First World]] (led by the United States) and the [[Second World]] (led by the Soviet Union).
 
*The [[Third Way (centrism)|"third way"]] is a political term applied to a variety of "third choice" options that some offer as an alternative to dichotomous situations which may otherwise appear polarized.
 
*The [[Third Way (centrism)|"third way"]] is a political term applied to a variety of "third choice" options that some offer as an alternative to dichotomous situations which may otherwise appear polarized.
Line 648: Line 657:
 
*There are three branches to the US government; executive, legislative, and judicial.
 
*There are three branches to the US government; executive, legislative, and judicial.
 
*[[Alvin Toffler]]'s ''[[The Third Wave (book)|The Third Wave]]'' considers that the late twentieth century saw the beginning of a third wave of change in post-industrial civilization after the [[Neolithic]] and the [[Industrial Revolution]].
 
*[[Alvin Toffler]]'s ''[[The Third Wave (book)|The Third Wave]]'' considers that the late twentieth century saw the beginning of a third wave of change in post-industrial civilization after the [[Neolithic]] and the [[Industrial Revolution]].
*The [[Third International]] supported Leninism.
+
*The [[Third International]] supported [[Leninism]].
 
*Cenocracy is the word coined to represent what is believed by some to be the next and superior step to present day forms of Democratic rule. It is based on the notion that before a society can truly achieve a government Of-By-and For the people, the people themselves must play a direct part (and not be represented vicariously) in the law-making process. To this end, every man, woman, and worker must have access to such a role, thus constituting a true 3rd branch legislative body. For example, each State in the United States would adopt an ongoing list of self-elected candidates from which the 3 aforementioned persons would be randomly selected to fulfill one-year terms of office with at least the same pay, privileges and legislative power commensurate to all other congressional members.
 
*Cenocracy is the word coined to represent what is believed by some to be the next and superior step to present day forms of Democratic rule. It is based on the notion that before a society can truly achieve a government Of-By-and For the people, the people themselves must play a direct part (and not be represented vicariously) in the law-making process. To this end, every man, woman, and worker must have access to such a role, thus constituting a true 3rd branch legislative body. For example, each State in the United States would adopt an ongoing list of self-elected candidates from which the 3 aforementioned persons would be randomly selected to fulfill one-year terms of office with at least the same pay, privileges and legislative power commensurate to all other congressional members.
  
==As a lucky or unlucky number==
+
==Lucky or unlucky number==
 
Three (三, formal writing: 叁, [[pinyin]] san1, [[Cantonese (linguistics)|Cantonese]]: saam1) is considered a [[numerology|good number]] in [[Chinese culture]] because it sounds like the word "alive" (生 pinyin sheng1, Cantonese: saang1), compared to [[4 (number)|four]] (四, pinyin: si4, Cantonese: sei3) that sounds like the word "death" (死 pinyin si3, Cantonese: sei2).
 
Three (三, formal writing: 叁, [[pinyin]] san1, [[Cantonese (linguistics)|Cantonese]]: saam1) is considered a [[numerology|good number]] in [[Chinese culture]] because it sounds like the word "alive" (生 pinyin sheng1, Cantonese: saang1), compared to [[4 (number)|four]] (四, pinyin: si4, Cantonese: sei3) that sounds like the word "death" (死 pinyin si3, Cantonese: sei2).
  
Counting to three is common in situations where a group of people wish to perform an action in [[synchrony]]: ''Now, on the count of three, everybody pull!'' &nbsp;Assuming the counter is proceeding at a uniform rate, the first two counts are necessary to establish the rate, but then everyone can predict when "three" will come based on "one" and "two"; this is likely why three is used instead of some other number.
+
Counting to three is common in situations where a group of people wish to perform an action in [[synchrony]]: ''Now, on the count of three, everybody pull!'' Assuming the counter is proceeding at a uniform rate, the first two counts are necessary to establish the rate, but then everyone can predict when "three" will come based on "one" and "two;" this is likely why three is used instead of some other number.
  
In Vietnam, it is bad luck to take a photo with three people in it.  
+
In Vietnam, some consider it bad luck to take a photo with three people in it.  
  
 
[[Luck]], especially bad luck, is often said to "come in threes."
 
[[Luck]], especially bad luck, is often said to "come in threes."
  
 
Some cultures in history have a place for people of [[third gender]] such as in Thailand.
 
Some cultures in history have a place for people of [[third gender]] such as in Thailand.
 
It is often believed that people die in threes. This only includes people in one's personal sphere (ie. directly impact on one's day-to-day life).
 
  
 
There is a superstition that states it is unlucky to take a third light, that is, to be the third person to light a cigarette from the same match or lighter. This is commonly believed to date from the trenches of the First World War when a sniper might see the first light, take aim on the second and fire on the third.
 
There is a superstition that states it is unlucky to take a third light, that is, to be the third person to light a cigarette from the same match or lighter. This is commonly believed to date from the trenches of the First World War when a sniper might see the first light, take aim on the second and fire on the third.
  
3 strikes and the player is out.
+
Three strikes and the player is out.
 
 
3rd time's the charm.
 
 
 
==In technology==
 
[[Image:U+2675 DejaVu Sans.svg|50px|right|3 as a resin identification code, used in recycling.]]
 
* The [[resin identification code]] used in recycling to identify [[polyvinyl chloride]].
 
*On [[computer keyboard]]s, in the United Kingdom the "3" key may be used to type the [[pound sign]] when pressed in combination with the shift key.
 
*On most telephone keypads, the "3" key is also associated with the letters "[[D]]," "[[E]]," and "[[F]]."
 
*In [[ASCII]], the code for "3" in hexadecimal is 33. This is the only character in ASCII such that a large file consisting of a single character has identical-looking hexadecimal and normal representation.
 
[[Image:Seven-segment 3.svg|25px|right]]
 
*The glyph "3" may be used as a substitute for [[yogh]] ({{unicode|Ȝ, ȝ}}) or [[Ze (Cyrillic)|ze]] ({{unicode|З, з}}) when those characters are not available.
 
*Three is the minimum odd number of voting components for simple easy [[redundancy checks]] by direct comparison.
 
*Three is approximately [[pi]] (actually closer to 3.14159) when doing rapid engineering wags or estimates. The same is true if one wants a rough-and-ready estimate of [[E (mathematical constant)|''e'']], which is actually approximately 2.7183.
 
*Some [[computer]] users may use "3" as an alternate to the letter "[[E]]," often in jest or to prevent search engines from reading their messages. This form of code is an example of basic [[Leetspeak]].
 
*"3" is the [[DVD region code]] for many East Asian countries, except for Japan (which is Region 2) and China (which is Region 6).
 
 
 
  
 +
It is commonly believed that "third time's the charm."
  
 
==In music==
 
==In music==
Line 694: Line 686:
 
*Any [[diatonic]] chord progression's [[key signature]] is made obvious with any 3 different triads, as opposed to potential key ambiguities with any 2 chords.
 
*Any [[diatonic]] chord progression's [[key signature]] is made obvious with any 3 different triads, as opposed to potential key ambiguities with any 2 chords.
  
*The [[tritone]], which divides the [[octave]] into 3 equally spaced notes (root, tritone, octave) is the rarest [[Interval (music)|interval]] of any [[Musical mode|mode]], only occurring semantically twice, and physically once. It is the only interval that, when inverted, remains unchanged functionally and harmonically.
+
*The [[tritone]], which divides the [[octave]] into 3 equally spaced notes (root, tritone, octave), is the rarest [[Interval (music)|interval]] of any [[Musical mode|mode]], occurring semantically only twice, and physically once. It is the only interval that, when inverted, remains unchanged functionally and harmonically.
  
*The 3/4 time signature of Western classical music tradition (Three beats to a measure, with the quarter note comprising the beat.) is said to represent the Holy Trinity of Christian doctrine, Father, Son and Holy Spirit. It is for this reason that it is often utilized in compositions which were written for use in ecclesiastical rites, or that are inspired by scriptural/spiritual themes and texts.
+
*The 3/4 time signature<ref>The 3/4 time signature refers to three beats to a measure, with the quarter note comprising the beat.</ref> of Western classical music tradition is said to represent the Holy Trinity of Christian doctrine, Father, Son and Holy Spirit. It is for this reason that it is often utilized in compositions which were written for use in ecclesiastical rites, or that are inspired by scriptural/spiritual themes and texts.
  
 
*In a standard [[jazz]] combo there are 3 necessary parts: bass, percussion, and chord maker.
 
*In a standard [[jazz]] combo there are 3 necessary parts: bass, percussion, and chord maker.
  
*3 is [[The Magic Number]] according to De La Soul.
+
*3 is [[The Magic Number]], according to De La Soul.
  
*[[3 (band)|3]] is a [[progressive metal]] group from Woodstock, NY.
+
==In Geography==
 +
[[Image:Flag of Sicily (revised).svg|thumb|400px|Flag of Trinacria with a [[Triskelion|three-legged symbol]].]]
  
==In Geography==
 
[[Image:Flag of Sicily (revised).svg|thumb|Flag of Trinacria with a [[Triskelion|three-legged symbol]].]]
 
 
*Several cities are known as [[Tripoli]] from Greek for "three cities."
 
*Several cities are known as [[Tripoli]] from Greek for "three cities."
 
*[[Sicilia]] was known as [[Trinacria]] for its triangle-shape.
 
*[[Sicilia]] was known as [[Trinacria]] for its triangle-shape.
*[[Three Mile Island]] is known for a nuclear accident.
 
 
==In filmography==
 
 
* ''[[Three (1969 film)|Three]]'' is a 1969 film starring Charlotte Rampling and Sam Waterston.
 
* ''[[Three (1965 film)|Three]]'' is a 1965 [[Cinema of Yugoslavia|Yugoslavian]] film directed by [[Aleksandar Petrović]].
 
* ''[[Three (film)|Three]]'' is a 2002 Asian horror movie collaboration.
 
* ''[[Thr3e (film)|Thr3e]]'' is a 2007 film adaptation of the novel of the same name by Ted Dekker.
 
* ''Three'', also known as ''[[Survival Island]]'' is a 2006 film starring Billy Zane and Kelly Brook.
 
*There is a 1977 film titled ''[[3 Women (film)|3 Women]]''.
 
*In both the film ''[[The Craft]]'' and the fantasy television series ''[[Charmed]]'', the ''"power of three"'' has been used as part of [[wiccan]] incantations.
 
*[[The Three Stooges]], a comedy group made up of "Larry, Moe, and Curly" and later "Larry, Moe, and Shemp" in the early- to mid-20th century.
 
  
 
==In sports==
 
==In sports==
*In [[Bowling]], 3 strikes in a row is called a turkey.
+
*In [[bowling]], 3 strikes in a row is called a turkey.
*In [[Cricket]], 3 outs in a row is called a hat trick.
+
*In [[cricket]], 3 outs in a row is called a hat trick.
 
*In [[ice hockey]], a game consists of 3 periods of twenty minutes each.
 
*In [[ice hockey]], a game consists of 3 periods of twenty minutes each.
 
*In [[rugby union]], 3 is the jersey number of the starting [[Rugby union positions#1. Loosehead prop & 3. Tighthead prop|tighthead prop]]. It is also the number of points received for a successful drop goal or penalty kick.
 
*In [[rugby union]], 3 is the jersey number of the starting [[Rugby union positions#1. Loosehead prop & 3. Tighthead prop|tighthead prop]]. It is also the number of points received for a successful drop goal or penalty kick.
*In [[baseball]], 3 is the number of strikes before the batter is [[strikeout|out]] and the number of outs per side per inning. It also represents the [[first baseman]]'s position. The number 3 position in the batting order is generally occupied by the team's best hitter. In high school and college, 3 is the maximum "drop" (inches of length minus ounces of weight) for a legal bat. 3 is the retired number of [[List of members of the Baseball Hall of Fame (alphabetical)|Baseball Hall of Fame]] players [[Babe Ruth]], [[Joe Medwick]], [[Bill Terry]], and [[Harmon Killebrew]]. [[Gary Sheffield]] and [[Ken Griffey Jr]] wear the number three.  
+
*In [[baseball]], 3 is the number of strikes before the batter is [[strikeout|out]] and the number of outs per side per inning. It also represents the [[first baseman]]'s position. The number 3 position in the batting order is generally occupied by the team's best hitter. In high school and college, 3 is the maximum "drop" (inches of length minus ounces of weight) for a legal bat.
 
*In [[basketball]], a shot made from [[three-point field goal|behind the three-point arc]] is worth 3 points. 3 is used to represent the [[small forward]] position.
 
*In [[basketball]], a shot made from [[three-point field goal|behind the three-point arc]] is worth 3 points. 3 is used to represent the [[small forward]] position.
*Is the number of the famous [[NASCAR]] [[stock car racing|stock car]] that [[Dale Earnhardt]] drove for nearly 20 years before his death in 2001. He won 6 out of his 7 championships while driving the #3 car. No one has driven the 3 car since his death. In [[IROC]], [[Helio Castroneves]] had his car number changed from his standard 3 (which he drives in the [[Indy Racing League]]) to number 03.
 
*Traditional number for the [[Tyrrell]] [[Formula One]] team's first car along with number 4 for the second until the end of the [[1995 Formula One Season]].
 
 
*A [[hat-trick]] in sports is associated with succeeding at anything three times in three consecutive attempts.
 
*A [[hat-trick]] in sports is associated with succeeding at anything three times in three consecutive attempts.
 
*In both American and [[Canadian football]], the number of points received for a successful [[Field goal (football)|field goal]].
 
*In both American and [[Canadian football]], the number of points received for a successful [[Field goal (football)|field goal]].
Line 735: Line 712:
 
*An [[Ironman triathlon]] consists of three events, a 2.4 mile (3.86 kilometer) swim, a 112 mile (180.2 kilometer) bike ride, and a 26.2 mile (42.2 kilometer) marathon run.
 
*An [[Ironman triathlon]] consists of three events, a 2.4 mile (3.86 kilometer) swim, a 112 mile (180.2 kilometer) bike ride, and a 26.2 mile (42.2 kilometer) marathon run.
 
*In [[football (soccer)|football]], number 3 is assigned in most cases to the left defender or [[fullback (football)|fullback]].
 
*In [[football (soccer)|football]], number 3 is assigned in most cases to the left defender or [[fullback (football)|fullback]].
*On March 24, 2006 the number 3 became the second number retired by the New Jersey Devils in honor of defenseman [[Ken Daneyko]].
 
  
 
==In literature==
 
==In literature==
Line 741: Line 717:
 
*3 is the number of novels or films in a [[trilogy]] and the number of interconnected works of art in a [[triptych]].
 
*3 is the number of novels or films in a [[trilogy]] and the number of interconnected works of art in a [[triptych]].
 
*The [[tricolon]] is often used for rhetorical effect.
 
*The [[tricolon]] is often used for rhetorical effect.
*[[Thr3e]] is a 2003 suspense novel written by Thriller author Ted Dekker.
 
 
*[[Dante Alighieri]]'s [[Divine Comedy]] has three parts each of thirty-three ''cantos'' (plus one introductory ''canto'' totaling 100). It was written in ''[[terza rima]]'', a combination of [[tercet]]s. All of this is an allusion to the Christian Trinity.
 
*[[Dante Alighieri]]'s [[Divine Comedy]] has three parts each of thirty-three ''cantos'' (plus one introductory ''canto'' totaling 100). It was written in ''[[terza rima]]'', a combination of [[tercet]]s. All of this is an allusion to the Christian Trinity.
 
*The number three recurs several times in [[Tolkien]]'s ''[[The Lord of the Rings]]'' and also in ''[[The Silmarillion]]''. Three Rings of Power were given to the [[Elf (Middle-earth)|Elves]]. There are three [[Silmarils]]. The unions of the [[Sundering of the Elves#Eldar|Eldar]] (Elves) and the [[Edain]] (Men) were three in number: [[Beren]] and [[Lúthien]], [[Tuor]] and [[Idril]], and (of course) [[Aragorn]] and [[Arwen]].
 
*The number three recurs several times in [[Tolkien]]'s ''[[The Lord of the Rings]]'' and also in ''[[The Silmarillion]]''. Three Rings of Power were given to the [[Elf (Middle-earth)|Elves]]. There are three [[Silmarils]]. The unions of the [[Sundering of the Elves#Eldar|Eldar]] (Elves) and the [[Edain]] (Men) were three in number: [[Beren]] and [[Lúthien]], [[Tuor]] and [[Idril]], and (of course) [[Aragorn]] and [[Arwen]].
Line 748: Line 723:
 
*[[The Three Sisters]] is a play by [[Anton Chekhov]].
 
*[[The Three Sisters]] is a play by [[Anton Chekhov]].
  
===Original scholarly articles/reviews about the three===
+
==In other fields==
* The Number Three in The American Culture. A selected chapter found in the book entitled "Every Man His Way" (1967- 68) by Alan Dundes.
+
[[Image:ICS Three.svg|right|thumb|350px|[[International maritime signal flag]] for 3 is known as a [[triband (flag)|triband]], a form of the [[tricolor]].]]
 +
[[Image:Orlowski podrozny.jpg|thumb|400px|Traveling in a troika (three-horse sled).]]
  
* "People in Threes Going Up in Smoke and Other Triplicities in Russian Literature and Culture" (Fall 2005, Rocky Mountain Review) by Lee B. Croft.
+
* The [[French Revolution]] espoused three values ([[liberty]], [[Social equality|equality]], [[:wikt:fraternity|fraternity]]).
 
+
* The flags of many nations have three colors, including the flags of the [[United States]], [[France]], [[Colombia]].
* "Buckland's Third Revolution" (1997- 98) and "Three Wise Men" (1984 - 85) posters by Herb O. Buckland.
 
 
 
==In other fields==
 
[[Image:ICS Three.svg|right|thumb|100px|[[International maritime signal flag]] for 3 is known as a [[triband (flag)|triband]], a form of the [[tricolour]].]]
 
[[Image:Orlowski podrozny.jpg|thumb|Travelling in a troika (three-horse sled).]]
 
{{otherusesof}}
 
'''Three''' is:
 
* Three are the values of [[French Revolution]] ([[liberty]], [[Social equality|equality]], [[:wikt:fraternity|fraternity]]) , and the colors of French flag. [[Colombian]] flag has three colors, meaning Gold, Water and Blood.
 
*[[3 (telecommunications)|Three]] is a mobile phone operator.
 
 
*The number of stars in "Pacific's triple star" in the ''[[God Defend New Zealand]]'', one of [[New Zealand]]'s two national anthems.
 
*The number of stars in "Pacific's triple star" in the ''[[God Defend New Zealand]]'', one of [[New Zealand]]'s two national anthems.
*The phrase "Third time's the charm" (or, rarely, "Three time's the charm") usually means that the third time a person attempts something, he or she will succeed
+
*The phrase "Third time's the charm" (or, rarely, "Three time's the charm") usually means that the third time a person attempts something, he or she will succeed.
 
*Three-bean salad is an appetizer containing three types of beans, such as [[kidney bean|kidney]], [[common bean|yellow]], and [[green bean|green]] beans.
 
*Three-bean salad is an appetizer containing three types of beans, such as [[kidney bean|kidney]], [[common bean|yellow]], and [[green bean|green]] beans.
 
*In most earlier video games, three lives were commonly given to players at the start.
 
*In most earlier video games, three lives were commonly given to players at the start.
 
*The [[television]] [[VHF]] channel most often used for hooking up [[VCR]]s and/or [[video game]] systems. If it is otherwise occupied by a local broadcaster, then channel 4 is used instead.
 
*The [[television]] [[VHF]] channel most often used for hooking up [[VCR]]s and/or [[video game]] systems. If it is otherwise occupied by a local broadcaster, then channel 4 is used instead.
 
*On most phones, the 3 key is associated with the letters [[D]], [[E]], and [[F]], but on the [[BlackBerry]] it is the key for [[U]] and [[I]].
 
*On most phones, the 3 key is associated with the letters [[D]], [[E]], and [[F]], but on the [[BlackBerry]] it is the key for [[U]] and [[I]].
*''"In Memory of 3"'' - a phrase about [[NASCAR]] driver [[Dale Earnhardt]], who drove the number 3 car. It can also refer to a 2004 [[ESPN]] [[television movie]] about Earnhardt's life called, ''[[3: The Dale Earnhardt Story]]''.
+
*The number 3 is often used as a [[literary device]] to provoke a feeling of unnaturalness, as [[2 (number)|twos]] are much more common in nature (pairs of [[Limb (anatomy)|limbs]], [[Cerebral hemispheres|hemispheres]], [[eyes]], and so forth). This is a prevailing [[theme (literature)|theme]] in [[Ray Bradbury]]'s novel [[Fahrenheit 451]]. The aliens and their machines in the 2005 film ''[[War of the Worlds (2005 film)|War of the Worlds]]'' were associated with features recurring in threes: eyes, legs, fingers, and so on, for this reason.
*[[No. 3]] - 1997 [[Korea]]n [[gangster]] [[comedy film|comedy]] written and directed by [[Neung-han Song]]
 
*In [[Astrology]], [[Gemini (astrology)|Gemini]] is the 3rd [[astrological sign]] of the [[Zodiac]].
 
*The number 3 is often used as a [[literary device]] to provoke a feeling of unnaturalness, as [[2 (number)|twos]] are much more common in nature ([[Limb (anatomy)|limbs]], [[Cerebral hemispheres|hemispheres]], [[eyes]], etc). This is a prevailing [[theme (literature)|theme]] in [[Ray Bradbury]]'s novel [[Fahrenheit 451]]. The aliens and their machines in the 2005 film ''[[War of the Worlds (2005 film)|War of the Worlds]]'' were associated with features recurring in threes: eyes, legs, fingers, etc, for this same reason.
 
 
 
 
* A [[tricycle]] has three wheels.
 
* A [[tricycle]] has three wheels.
* The standard number of lives in many arcade video games, such as [[Pac-Man]], [[Sonic the Hedgehog (video game)|Sonic the Hedgehog]] and [[Mega Man (video game)|Mega Man]].{{Fact|date=March 2008}}
+
* Three Giza Pyramids: [[Khufu]], [[Khafre]], and [[Menkaure]] ([[Giza pyramid complex]]).
* In Archeology- three Giza Pyramids: [[Khufu]], [[Khafre]], and [[Menkaure]] ([[Giza pyramid complex]]).
 
  
 
== See also ==
 
== See also ==
 
 
* [[Arithmetic]]
 
* [[Arithmetic]]
 
* [[Integer]]
 
* [[Integer]]
Line 787: Line 748:
  
 
==References==
 
==References==
 
+
* Flegg, Graham. ''Numbers: Their History and Meaning.'' Mineola, NY: Dover Publications, 2002. ISBN 0486421651.
* Flegg, Graham. 2002. ''Numbers: Their History and Meaning.'' Mineola, NY: Dover Publications. ISBN 0486421651.
+
* Ifrah, Georges. ''The Universal History of Numbers: From Prehistory to the Invention of the Computer.'' Translated by David Bellos et al. New York: Wiley, 2000. ISBN 0471393401.
 
+
* McLeish, John. ''The Story of Numbers: How Mathematics Has Shaped Civilization.'' New York: Fawcett Columbine, 1994. ISBN 0449909387.
* Ifrah, Georges. 2000. ''The Universal History of Numbers: From Prehistory to the Invention of the Computer.'' Translated by David Bellos et al. New York: Wiley. ISBN 0471393401.
+
* Menninger, Karl. ''Number Words and Number Symbols: A Cultural History of Numbers.'' New York: Dover Publications, 1992. ISBN 0486270963.
 
+
* Wells, D. G. ''The Penguin Dictionary of Curious and Interesting Numbers.'' London, UK: Penguin Books, 1998. ISBN 0140261494.
* McLeish, John. 1994. ''The Story of Numbers: How Mathematics Has Shaped Civilization.'' New York: Fawcett Columbine. ISBN 0449909387.
 
 
 
* Menninger, Karl. 1992. ''Number Words and Number Symbols: A Cultural History of Numbers.'' New York: Dover Publications. ISBN 0486270963.
 
 
 
* Wells, D. G. 1998. ''The Penguin Dictionary of Curious and Interesting Numbers.'' Rev. ed. London, UK: Penguin Books. ISBN 0140261494.
 
  
 
==External links==
 
==External links==
 
+
All links retrieved June 13, 2023.
* [http://www.learner.org/resources/series171.html Learning Math: Number and Operations.] Teacher Resources/Mathematics. Retrieved August 15, 2008.
+
* [https://teachers.net/lessons/posts/3203.html Number "3" and "recycling"] ''Teachers.net''.  
 
+
* Dr. John A. McNulty. [http://www.meddean.luc.edu/lumen/MedEd/GrossAnatomy/Threes.html List of Three's in Anatomy.]  
* [http://www.themathwebsite.com/ListOfTopics.php www.TheMathWebSite.com.] High School Math Teacher Lessons Tests Quizzes Enrichment. Retrieved August 18, 2008.
 
 
 
* [http://teachers.net/lessons/posts/3203.html Number "3" and "recycling".] teachers.net. Retrieved August 19, 2008.  
 
 
 
* [http://threes.com/ The Book of Threes.] threes.com. Retrieved August 19, 2008.
 
 
 
* Dr. John A. McNulty. 2006. [http://www.meddean.luc.edu/lumen/MedEd/GrossAnatomy/Threes.html List of Three's in Anatomy.] Retrieved August 19, 2008.
 
  
 
[[Category:Physical sciences]]
 
[[Category:Physical sciences]]

Latest revision as of 06:44, 13 June 2023

This article is about the number three.
3

0 1 2 3 4 5 6 7 8 9 >>

List of numbers — Integers

0 10 20 30 40 50 60 70 80 90 >>

Cardinal 3
three
Ordinal 3rd
third
Numeral system ternary
Factorization prime
Divisors 1, 3
Roman numeral III
Roman numeral (Unicode) Ⅲ, ⅲ
Arabic ٣
Ge'ez
Bengali
Chinese numeral 三,弎,叁
Devanāgarī
Hebrew ג (Gimel)
Khmer
Thai
prefixes tri- (from Greek)

tre-/ter- (from Latin)

Binary 11
Octal 3
Duodecimal 3
Hexadecimal 3

3 (three) is a number, numeral, and glyph that represents the number. It is the natural number[1] that follows 2 and precedes 4. It is an integer and a cardinal number, that is, a number that is used for counting.[2] In addition, it is classified as a real number,[3] distinguishing it from imaginary numbers.

Evolution of the glyph

The number three was once written with as many lines as the number represents. The Romans tired of writing 4 as IIII, but 3 continues to be written as three lines in Roman and Chinese numerals. This was the way the Brahmin Indians wrote it, and the Gupta made the three lines more curved. The Nagari started rotating the lines clockwise, ending each line with a slight downward stroke on the right. Eventually, they made these strokes connect with the lines below, transforming it to a character that looks very much like a modern 3 with an extra stroke at the bottom.

Evolution3glyph.png

The Western Ghubar Arabs finally eliminated the extra stroke and created our modern 3. The extra stroke, however, was very important to the Eastern Arabs, who made it much larger, while rotating the strokes above to lie along a horizontal axis. To this day, Eastern Arabs write a 3 that looks like a mirrored 7 with ridges on its top line: ٣[4]

While the shape of the 3 character has an ascender in most modern typefaces, in typefaces with text figures the character usually has a descender, for example, in TextFigs036.png. In some French text-figure typefaces, though, it has an ascender instead of a descender.

A common variant of the digit 3 has a flat top, similar to the character Ʒ (ezh), sometimes used to prevent people from falsifying a 3 into an 8.

In mathematics

Three is the first odd prime number, and the second smallest prime. It is both the first Fermat prime (2 + 1) and the first Mersenne prime (2² - 1), as well as the first lucky prime. However, it's the second Sophie Germain prime, the second Mersenne prime exponent, the second factorial prime (2! + 1), the second Lucas prime, the second Stern prime.

Three is the first unique prime, based on the properties of its reciprocal.

Three is the third Heegner number.

Three is the second triangular number and it is the only prime triangular number. Three is the only prime which is one less than a perfect square. Any other number which is n² - 1 for some integer n is not prime, since it is (n - 1)(n + 1). This is true for 3 as well, but in its case one of the factors is 1.

Three non-collinear points determine a plane and a circle.

Three is the fourth Fibonacci number and the third that is unique. In the Perrin sequence, however, 3 is both the zeroth and third Perrin numbers.

Vulgar fractions with 3 in the denominator have a single digit repeating sequences in their decimal expansions, (.000…, .333…, .666…)

A natural number is divisible by three if the sum of its digits in base 10 is divisible by 3. For example, the number 21 is divisible by three (3 times 7) and the sum of its digits is 2 + 1 = 3. Because of this, the reverse of any number that is divisible by three (or indeed, any permutation of its digits) is also divisible by three. For instance, 1368 and its reverse 8631 are both divisible by three (and so are 1386, 3168, 3186, 3618, and so on).

A triangle is the most durable shape possible, the only "perfect" figure that, if all endpoints have hinges, will never change its shape unless the sides themselves are bent.

3 is the only integer between the mathematical constants e and π.

Three of the five regular polyhedra have triangular faces—the tetrahedron, the octahedron, and the icosahedron. Also, three of the five regular polyhedra have vertices where three faces meet—the tetrahedron, the hexahedron (cube), and the dodecahedron. Furthermore, only three different types of polygons comprise the faces of the five regular polyhedra—the triangle, the quadrilateral, and the pentagon.

There are only three distinct 4×4 panmagic squares.

Only three tetrahedral numbers are also perfect squares.

In numeral systems

It is frequently noted by historians of numbers that early counting systems often relied on the three-patterned concept of "One- Two- Many" to describe counting limits. In other words, in their own language equivalent way, early peoples had a word to describe the quantities of one and two, but any quantity beyond this point was simply denoted as "Many." As an extension to this insight, it can also be noted that early counting systems appear to have had limits at the numerals 2, 3, and 4. References to counting limits beyond these three indices do not appear to prevail as consistently in the historical record.

Base Numeral system
2 binary 11
3 ternary 10
over 3 (decimal, hexadecimal) 3

List of basic calculations

Multiplication
Multiplication 1 2 3 4 5 6 7 8 9 10
3 6 9 12 15 18 21 24 27 30
Multiplication 11 12 13 14 15 16 17 18 19 20
33 36 39 42 45 48 51 54 57 60
Multiplication 21 22 23 24 25 50 100 1000
63 66 69 72 75 150 300 3000
Division
Division 1 2 3 4 5 6 7 8 9 10
3 1.5 1 0.75 0.6 0.5 0.375 0.3
1 2 3
Division 11 12 13 14 15
0.25 0.2
4 5
Exponentiation
Exponentiation 1 2 3 4 5 6 7 8 9 10
3 9 27 81 243 729 2187 6561 19683 59049
1 8 27 64 125 216 343 512 729 1000
Exponentiation 11 12 13
177147 531441 1594323
1331 1728 2197

In science

Astronomy

  • Earth is the third planet from the Sun.
  • There are three types of galaxies: Elliptical, spiral, and irregular.
  • Globular Cluster M3 (also known as Messier Object 3 or NGC 5272) is a globular cluster in the Canes Venatici constellation.
  • The Roman numeral III stands for giant star in the Yerkes spectral classification scheme.
  • The Roman numeral III (usually) stands for the third-discovered satellite of a planet or minor planet (for example, Pluto III)
  • In the constellation Orion, the "belt" is made up of 3 stars in a row.

Biology

Classification of biological forms
  • 3 basic life domains: Archaea, Bacteria, and Eucarya
  • 3 phyla of Archaebacteria that are found mainly in extreme habitats where little else can survive: Methanogens, Halophiles, Thermoacidophiles.

3 distinct species of the genus Homo:

  1. Homo habilis "capable man"
  2. Homo erectus "upright man"
  3. Homo sapiens "wise man"

3 distinct species of the genus Paranthropus:

  1. Paranthropus robustus
  2. Paranthropus boisei
  3. Paranthropus aethiopicus

3 Proconsul species:

  1. Proconsul africanus
  2. Proconsul major
  3. Proconsul nyanzae

3 Pan troglodyte sub-species:

  1. Pan Troglodytes Schweinfurthii- (Eastern Common Chimpanzee)
  2. Pan Troglodytes Troglodytes- (Central Common Chimp)
  3. Pan Troglodytes Verus- (Western Common Chimp)

3 types of primates:

  1. Prosimians
  2. Monkeys (old & new world)
  3. Apes (lesser & greater apes, as well as humans)

3 social group types of the Great Apes:

  1. Orangutans (Solitary—little amount of both sexes)
  2. Gorillas (Harems—great amount of one sex)
  3. Common Chimps (Live in territories defended by related males—great amount of both sexes)

Three traditional families of hominoid:

  1. Hylobatidae: Include the so-called lesser apes of Asia, the gibbons and siamangs.
  2. Hominidae: Include living humans and typically fossil apes that possess a suite of characteristics such as bipedalism, reduced canine size, and increasing brain size such as the australopithecines.
  3. Pongidae: Include the remaining African great apes including gorillas, chimpanzees, and the Asian orangutan.
Molecular biology
  • The information in DNA and RNA is stored and transmitted in the form of a triplet codon system.
Anatomy
  • A human ear has three semicircular canals.
  • A human middle ear has three ossicles.
Physiology
  • 3 distinct Cytoskeleton components: Microtubules, Intermediate Filament, Actin Filaments
  • 3 primary cellular energy molecules: AMP, ADP, ATP
  • 3 main fatty acid categories: Saturated, Monounsaturated, Polyunsaturated
  • 3 substances metabolized for energy needs: Carbohydrates, Fats, Proteins
  • Triglycerides are the main storage forms of fatty acids.
  • 3 primary germ layers of a mammalian embryo: Endoderm, Mesoderm, Ectoderm.
Plants and Animals
  • Triceratops: Cretaceous period dinosaur with three horns on its head.
  • Shamrock: refers to one of several trifoliate (three-leaved) plants of the Leguminosae family which includes the clover.
  • 3-bodied general description of insects: Head, Thorax, Abdomen.
  • Trilobite: hard-bodied invertebrate marine arthropod of the Paleozoic era with three lobes.
  • Monocotyledon: A monocot's flower is often trimerous, with the flower parts in threes or in multiples of three (typically three, six, or nine petals).

Chemistry

  • Three is the atomic number of lithium.
  • Atoms consist of three types of constituents: Protons, neutrons, and electrons.
  • 3 types of molecular bonds: Covalent, Ionic, and Polar Covalent (Dative or Coordinate).
  • 3 types of isomerism: Structural (Ethyl alcohol), Geometric (Maleic acid), and Optical (L-Lactic acid).
  • 3 types of hydrocarbon chains: Straight (Propane), Branched (Isobutane), and Circular (Cyclopropane).

Geology

  • Three basic planes: Above, Surfaced, Beneath.
  • Three fundamental divisions of Earth's layers: Core, Mantle, and Crust.
  • Three main types of rock formations: Igneous, Metamorphic, and Sedimentary.
  • 3 types of earthquake waves: P (Primary) waves, S (Secondary) waves, and L/R (Love & Rayleigh) waves.
  • 3 types of volcanoes: Cinder cones, Shield volcano, and Composite volcano.

Physics

  • White light is composed of a mixture of the three additive primary hues: Red, green, and blue.
Particle physics
  • There are three generations of fundamental leptons (electron, muon, tauon and their neutrinos) and three groups of flavors of quarks (up-down, charmed-strange, top-bottom).
  • A neutron consists of three quarks: Two down quarks and one up quark.
  • Nature defines the state of supersymmetry as ±0 (left- and right-handed). This allows additional variations with respect to the breaking of supersymmetry involving the number three. The whole spectrum of possibilities based on the number three thus is duplicated for matter and antimatter.
  • Three is realized as 0 1 2 in the number of exponents defining the basic kinds of spin. These are ½*2^0 ħ (fermionic), ½*2^1 ħ (bosonic), ½*2^2 ħ (gravitational). The bosonic state is the symmetric state.
  • Changes of spin, appearing as changes of flavor, can be by only three multiples of a fundamental angular quantum of spin causing an 1/3 elementary charge e. The down quark only can change its spin from -1 to +2, the up-quark. A supersymmetric superstring can break supersymmetry from -0 to -3 (electron) or from +0 to +3 (positron). The electron anti-neutrino (+3) and electron neutrino (-3)represent three quanta of fermionic spin within the spacetime metric (no superstrings/particles), conserving supersymmetry globally.
  • Three non-gravitational forces actively are generated by three different superstring spin functionalities, while gravity is a passive reaction of spacetime due to the presence of superstrings with broken supersymmetry.
  • Three represents an optimum of economy in a physical geometrical realization and a maximum of functionality at the same time. This limits the otherwise nearly infinite number of degrees of freedom by a defined geometry with a specific functionality to exactly the ones needed to generate the fundamental basis for the expression of the "Everything."
  • The number three is shown to be represented by different possible spin states in the regime from -3 to +3, that is by negative and positive integer numbers, including a -0 and +0, in contrast to mathematics where 0 is an integer number without sign. Due to geometrically defined quanta of spin, the superstring shows a physical realization of integer numbers between -3 and +3. This answers Roger Penrose's question of the physical meaning of integer numbers (Road to Reality, p. 65) and their relevance in the physical world.
  • Three different states of string tension exist. The whole geometry and functionality is the same with exception of the orthogonal magnetic flux component causing gravo-magnetic mass. Thus three generations of particles can exist solely according to energetic conditions. The basic relevance of the number three for the superstring in no way is touched.
  • Three is the smallest number that, in a physical realization, on breaking of symmetry allows the emergence of two additional functionalities different from the one of a central state. These either can be symmetric as in -3 (±0) +3 (electron, two supersymmetric superstrings (left/right-handed, no matter particles, dark), and the positron) or asymmetric as in -1 (-0) +2 (quarks) or -2 (+0) +1 (anti quarks). This means, breaking of a symmetry also can result in one of two different asymmetric states. In this case supersymmetry globally is conserved on the average by the properties of three quarks (enforced quark confinement). Multiplication of these angular spins by 1/3 gives the three particle charges, negative or positive are defined by the direction of angular spin.

In technology

3 as a resin identification code, used in recycling.
  • Three is the resin identification code used in recycling to identify polyvinyl chloride.
  • In ASCII, the code for "3" in hexadecimal is 33. This is the only character in ASCII such that a large file consisting of a single character has identical-looking hexadecimal and normal representation.
Seven-segment 3.svg
  • Three is approximately pi (which is closer to 3.14159) when doing rapid engineering wags or estimates. The same is true if one wants a rough-and-ready estimate of e, which is approximately 2.7183.
  • Some computer users may use "3" as an alternate to the letter "E," often in jest or to prevent search engines from reading their messages. This form of code is an example of basic Leetspeak.
  • "3" is the DVD region code for many East Asian countries, except for Japan (which is Region 2) and China (which is Region 6).
  • The glyph "3" may be used as a substitute for yogh (Ȝ, ȝ) or ze (З, з) when those characters are not available.
  • Three is the minimum odd number of voting components for simple easy redundancy checks by direct comparison.

In history

  • Christian Jürgensen Thomsen proposed the three-age system to divide prehistory in the Stone, Bronze and Iron Ages.
  • 3rd Reich of Germany: Adolf Hitler's Empire
  • 3rd Rome: Old name for Russia
  • 3rd Estate: French Revolution
  • 3rd Way: Mussolini's social movement
  • 3rd Wave: Journalistic name given to Newt Gingrich's social movement (U.S.)
  • Third Communist International was founded in 1919 by Vladimir Ilyich Lenin (He died after a 3rd stroke).

In religion

Abrahamic religions

The Shield of the Trinity is a diagram of the Christian doctrine of the Trinity.

Christianity

  • In the Christian concept of the Holy Trinity, God is a single being with three persons: The Father, Son and Holy Spirit.
  • Three Wise Men visited Jesus after his birth and brought him three gifts.
  • Jesus had three main disciples.
  • Jesus' main ministry lasted for 3 years before his crucifixion.
  • Jesus rose from the dead on the third day after his death.
  • Jesus predicted that Peter would deny him three times.
  • Paul's first letter to the Corinthians (1 Cor 13:13) mentions three theological virtues: faith, hope, and love.
  • In Roman Catholicism, there are three groups of martyrs, collectively known as Faith, Hope, and Charity (named after the Theological Virtues).
  • Catholicism also mentions three divisions in the spiritual world: Heaven, Hell, and Purgatory (or Limbo).

Judaism

  • The three Patriarchs: Abraham, Isaac, and Jacob.
  • King Solomon states in Ecclesiastes 4:12: "A three-ply cord is not easily severed."
  • The three pilgrim festivals (Sheloshet HaRegalim): Passover, Shavuot, and Sukkot.
  • The three leaders of the Jewish nation during their 40 years of wandering in the desert: Moses, Aaron, and Miriam.
  • The Tanakh is comprised of 3 sections: Torah, Nevi'im, and Ketuvim
  • There are 3 daily prayer services: Shacharit, Mincha, and Maariv
  • Shimon Hatzaddik taught: "On three things the world stands: On Torah, on prayer, and on acts of kindness" (Pirkei Avoth 1:2). Rabban Shimon ben Gamliel taught: "The world continues to exist because of three things: justice, truth, and peace" (ibid. 1:18).

Islam

  • In Muslim devotional rites, certain formulas are repeated three times, and others, thirty-three times.
  • A devout Muslim tries to make a pilgrimage to all three holy cities of Islam: Mecca, Medina, and Jerusalem.

Zoroastrianism

  • In their daily prayers, Zoroastrians commit themselves to pursuing three types of goodness: good thoughts, good words, and good deeds.
  • At the same time, they pray to reject three types of evil: Evil thoughts, evil words, and evil deeds.

Hinduism

  • 3 main aspects of God (Trimurti) in Hinduism: Brahma, Vishnu, and Shiva (Maheshwara).
  • The three Gunas underlie action, in the Vedic system of knowledge.
  • The three Vedas are called trayi, that is, triad.
  • Lord Shiva is Trinetra, or three-eyed.
  • The famous "Triveni" is the confluence of three holy rivers: Ganga, Yamuna, and the hidden Sarasvati.

In Buddhism

  • The Triple Gem—Buddha, Dhamma (Buddha's teaching) and Sangha (the preachers of Dhamma).
  • The Triple Bodhi (ways to understand the end of birth)—Budhu, Pasebudhu, Mahaarahath
  • Buddhism's three refuges are called "Trisharana:" Buddhan sharanam gacchami, Dhammam sharanam gacchami, Sangham sharanam gacchami.

Other religions

  • Wiccans have a Rule of Three.
  • Taoism teaches about the Three Pure Ones.

In mythology

  • 3 Greek gods: Zeus, Poseidon, Hades (Air, Water, Earth)
  • 3 Roman gods: Jupiter, Neptune, Pluto (Air, Water, Earth)
  • 3 mysterious figures amongst Norse gods: Hoenir, Lodurr, Mimir.
  • Ancient Egypt Theban Triad: Amun, Mut, and their son Khans.
  • 3 ancient Egyptian central religious figures: Horus, Isis, Osiris.
  • The Maya believed 3 stars in the Orion Constellation (Alnitak, Saiph, Rigel) were arranged by the gods as a triangular hearth, enclosing the smoke of the fire creation—the nebula.
  • 3 Greek Fates (Moirai, Moirés): Clotho, Lachesis, Atropos (sometimes referred to as the 3 spinners).
  • 3 Roman Fates: Decima, Nona (goddesses of birth), Morta (goddess of death)
  • 3 Roman Graces (or the Charities in Greek mythology, and according to the Spartans, Cleta was the third): Aglaia, Euphrosyne, Thalia.
  • 3 parts to a Chimera: Head of a lion, body of a goat, tail of a snake.
  • 3-faced goddess in Greek Mythology: Hecate
  • 3 Gorgons-(snake-haired sisters in Greek mythology): Stheno, Euryale, Medusa are sometimes depicted as having wings of gold, brazen claws, and the tusks of boars. Medusa is the only one of the gorgons that is mortal.
  • 3 different beings made up the different qualities of death according to ancient Greek belief: Thantos (male), Ker (female), Gorgo (female).
  • 3 Roman Furies (female personifications of vengeance) that were called the Erinyes (the Angry Ones) or Eumenides by the Ancient Greeks (Orestes called them the Solemn Ones, or the Kindly Ones): Alecto ("unceasing"), Megaera ("grudging"), Tisiphone ("avenging murder").
  • 3-headed dog that guarded the gate to Hades in Greek Mythology: Cerberus
  • 3 ancient Greek Harpies: Aello, Ocypete, and Celaeno.

In philosophy

3-patterned Philosophical Distinctions
St. Augustine's Philosophy: Memory~ Understanding~ Will
Aquinas' 3 transcendentals of being: Unity~ Truth~ Goodness
Aquinas' 3 requisites for the beautiful: Wholeness or perfection~ Harmony or due proportion~ Radiance
Aquinas' 3 logical faculties (based in Aristotle) Conception~ Judgment~ Reasoning
Aquinas' 3 causal principles (based in Aristotle) Agent~ Patient~ Act
Comte's Philosophy: Great Being~ Great Medium~ Great Fetish
Hegel's 3 Spirits: Subjective Spirit~ Objective Spirit~ Absolute Spirit
Plotinus' Philosophy: One~ One Many~ One and Many
Aristotle's 3 Unities: Unity of Action~ Unity of Time~ Unity of Place
Francis Bacon's 3 Tables: Presence~ Absence~ Degree
Thomas Hobbes' 3 Fields: Physics~ Moral Philosophy~ Civil Philosophy
Immanuel Kant's 3 Critiques: Pure Reason~ Practical Reason~ Judgment
Averroes' 3 Commentaries: Little~ Middle~ Great
Karl Marx's 3 isms: Communism~ Socialism~ Capitalism
Woodrow Wilson's 3 isms: Colonialism~ Racism~ Anti-Communism
Hippocrates' Mind Disorders: Mania~ Melancholia~ Phrenitis
Emile Durkheim's 3 Suicides: Egoistic~ Altruistic~ Anomic
David Riesman's 3 Social Characters: Tradition-directed~ Inner-directed~ Other-directed
Erich Fromm's 3 Symbols: The Conventional~ The Accidental~ The Universal
Pythagoras' "fusion" idea: Monarchy~ Oligarchy~ Democracy (into harmonic whole)
Martin Luther King Jr.'s "Middle Road": Acquiescence~ Nonviolence~ Violence
Kierkegaard's 3 Stages: Aesthetic~ Ethical~ Religious
Husserl's 3 Reductions: Phenomenological~ Eidetic~ Religious
St. Augustine's 3 Laws: Divine Law~ Natural Law~ Temporal, or positive Law
Witness Stand truths: The Truth~ The whole Truth~ Nothing but the Truth
Lucretius' 3 Ages: Stone Age~ Bronze Age~ Iron Age
Feuerbach's 3 Thoughts: God, 1st Thought~ Reason, 2nd~ Man, 3rd
Albertus Magnus' 3 Universals: Ante Rem~ In Rem~ Post Rem
Max Weber's 3 Authorities: Traditional~ Charismatic~ Legal-rational
Ferdinand de Saussure's 3 "Signs": Sign~ Signified~ Signifier
Charles Peirce's 3 semiotic elements Sign~ Object~ Interpretant
Charles Pierce's 3 categories: Quality of feeling~ Reaction/resistance~ Representation
Charles Peirce's 3 universes of experience: Ideas~ Brute fact~ Habit (habit-taking)
Charles Peirce's 3 normatives: The good (esthetic)~ The right (ethical)~ The true (logical)
Charles Peirce's 3 grades of conceptual clearness By familiarity~ Of definition's parts~ Of conceivable practical consequences
Charles Peirce's 3 modes of evolution: Fortuitous variation~ Mechanical necessity~ Creative love
John Maynard Keynes's 3 Eras: Scarcity~ Abundance~ Stabilization
George Mead's 3 Distinctions: Self~ I~ Me
Frederic Thrasher's 3-group Gangs: Inner Circle~ Rank & File~ Fringers
Abraham Lincoln's 3-For-All: Of the People~ By the People~ For the People
Samuel Clemmons' (Mark Twain) 3 lies: Lies~ Damned Lies~ Statistics
J.W.S. Pringle's 3 intellectual problems: Religious & Ethical~ Practical~ Scientific
Jerome Bruner's 3 cognitive processing modes: Enactive~ Iconic~ Symbolic
Wilhelm Wundt's 3 mind elements: Sensations~ Images~ Feelings
Robert Sternberg's 3 love components: Passion~ Intimacy~ Commitment
Robert Sternberg's Triarchic Intelligence: Analytic~ Creative~ Practica
Paul D. Maclean's Triune Brain: R-System (Reptilian)~ Limbic System~ Neocortex
3-monkey Philosophy: Hear no Evil~ See no Evil~ Speak no Evil
Jerry Fodor's mind Taxonomy: Central Processes~ Input Processes~ Transducers
Plato's Tripartite soul: Rational~ Libidinous~ Spirited (various animal qualities)
Hjalmar Wennerberg's philosophy orders: Phenomenology~ Normative Science~ Metaphysics
William Herbert Sheldon's body types: Endomorph~ Mesomorph~ Ectomorph
Ernst Kretschmer's body types: Pyknic~ Asthenic~ Athletic
Aristotle's 3 in 1 idea: Mind~ Self-knowledge~ Self-love
Kenneth Craik's 3 reasoning processes: Translation~ Reasoning~ Retranslation
Francis Galton's 3 genius traits: Intellect~ Zeal~ Power of working

In Education

  • 3 R's: Reading, 'Riting, 'Rithmetic.
  • 3 levels: Primary (Elementary) Education, Secondary (Jr. and Sr. High) Education, Tertiary (College, University, Polytechnical Institute, TAFE) Education.
  • 3 levels of University degrees: Bachelor's, Maste, Doctor's (Ph.D., M.D., J.D., and so on)
  • 3 University distinctions at graduation: Cum Laude, Magna Cum Laude, Summa Cum Laude.
  • 3 good grade divisions: A, B, C
  • 3 levels to each grade formula: A+ (A plus), A (A neutral), A- (A minus)

In politics

Christ sorting people into prayers, protectors and workers.
  • Plato split his utopian city into three populations: laborers, guardians (warriors), and philosophers (rulers)
  • Several polities have been ruled by three persons in a triumvirate or a troika.
  • Medieval theory divided society in laboratores (peasants), bellatores (noble warriors) and oratores (clergy). An earlier division had only the potentes ("powerful," warriors) and the powerless.
  • In the Ancient Regime, the estates of the realm (for example, the French Estates General) were divided in a branch for aristocracy, another for the Catholic hierarchy and the Third Estate for rich peasants and bourgeoisie. The triumph of the Third Estate is the French Revolution.
  • By analogy to the Third Estate, the Third World (poor countries or non-aligned countries) was defined as different from the First World (led by the United States) and the Second World (led by the Soviet Union).
  • The "third way" is a political term applied to a variety of "third choice" options that some offer as an alternative to dichotomous situations which may otherwise appear polarized.
  • After the fall of Constantinople, the Tsars considered Moscow as the Third Rome.
  • Also Nazism considered Nazi Germany the Third Reich after the Holy Roman Empire and the Prussian Empire.
  • There are three branches to the US government; executive, legislative, and judicial.
  • Alvin Toffler's The Third Wave considers that the late twentieth century saw the beginning of a third wave of change in post-industrial civilization after the Neolithic and the Industrial Revolution.
  • The Third International supported Leninism.
  • Cenocracy is the word coined to represent what is believed by some to be the next and superior step to present day forms of Democratic rule. It is based on the notion that before a society can truly achieve a government Of-By-and For the people, the people themselves must play a direct part (and not be represented vicariously) in the law-making process. To this end, every man, woman, and worker must have access to such a role, thus constituting a true 3rd branch legislative body. For example, each State in the United States would adopt an ongoing list of self-elected candidates from which the 3 aforementioned persons would be randomly selected to fulfill one-year terms of office with at least the same pay, privileges and legislative power commensurate to all other congressional members.

Lucky or unlucky number

Three (三, formal writing: 叁, pinyin san1, Cantonese: saam1) is considered a good number in Chinese culture because it sounds like the word "alive" (生 pinyin sheng1, Cantonese: saang1), compared to four (四, pinyin: si4, Cantonese: sei3) that sounds like the word "death" (死 pinyin si3, Cantonese: sei2).

Counting to three is common in situations where a group of people wish to perform an action in synchrony: Now, on the count of three, everybody pull! Assuming the counter is proceeding at a uniform rate, the first two counts are necessary to establish the rate, but then everyone can predict when "three" will come based on "one" and "two;" this is likely why three is used instead of some other number.

In Vietnam, some consider it bad luck to take a photo with three people in it.

Luck, especially bad luck, is often said to "come in threes."

Some cultures in history have a place for people of third gender such as in Thailand.

There is a superstition that states it is unlucky to take a third light, that is, to be the third person to light a cigarette from the same match or lighter. This is commonly believed to date from the trenches of the First World War when a sniper might see the first light, take aim on the second and fire on the third.

Three strikes and the player is out.

It is commonly believed that "third time's the charm."

In music

  • In music, the Roman numeral iii is the mediant scale degree, chord, or diatonic function, when distinguished III = major and iii = minor.
  • Three is the number of performers in a trio.
  • There are 3 notes in a triad, the most important and basic form of any chord.
  • Any diatonic chord progression's key signature is made obvious with any 3 different triads, as opposed to potential key ambiguities with any 2 chords.
  • The tritone, which divides the octave into 3 equally spaced notes (root, tritone, octave), is the rarest interval of any mode, occurring semantically only twice, and physically once. It is the only interval that, when inverted, remains unchanged functionally and harmonically.
  • The 3/4 time signature[5] of Western classical music tradition is said to represent the Holy Trinity of Christian doctrine, Father, Son and Holy Spirit. It is for this reason that it is often utilized in compositions which were written for use in ecclesiastical rites, or that are inspired by scriptural/spiritual themes and texts.
  • In a standard jazz combo there are 3 necessary parts: bass, percussion, and chord maker.
  • 3 is The Magic Number, according to De La Soul.

In Geography

Flag of Trinacria with a three-legged symbol.
  • Several cities are known as Tripoli from Greek for "three cities."
  • Sicilia was known as Trinacria for its triangle-shape.

In sports

  • In bowling, 3 strikes in a row is called a turkey.
  • In cricket, 3 outs in a row is called a hat trick.
  • In ice hockey, a game consists of 3 periods of twenty minutes each.
  • In rugby union, 3 is the jersey number of the starting tighthead prop. It is also the number of points received for a successful drop goal or penalty kick.
  • In baseball, 3 is the number of strikes before the batter is out and the number of outs per side per inning. It also represents the first baseman's position. The number 3 position in the batting order is generally occupied by the team's best hitter. In high school and college, 3 is the maximum "drop" (inches of length minus ounces of weight) for a legal bat.
  • In basketball, a shot made from behind the three-point arc is worth 3 points. 3 is used to represent the small forward position.
  • A hat-trick in sports is associated with succeeding at anything three times in three consecutive attempts.
  • In both American and Canadian football, the number of points received for a successful field goal.
  • In Canadian football, the last down before a team loses possession on downs. Usually, a team faced with a third down will punt (if far from the opponent's goal line) or attempt a field goal (if relatively close).
  • An Ironman triathlon consists of three events, a 2.4 mile (3.86 kilometer) swim, a 112 mile (180.2 kilometer) bike ride, and a 26.2 mile (42.2 kilometer) marathon run.
  • In football, number 3 is assigned in most cases to the left defender or fullback.

In literature

  • 3 is the number of words or phrases in a Tripartite motto.
  • 3 is the number of novels or films in a trilogy and the number of interconnected works of art in a triptych.
  • The tricolon is often used for rhetorical effect.
  • Dante Alighieri's Divine Comedy has three parts each of thirty-three cantos (plus one introductory canto totaling 100). It was written in terza rima, a combination of tercets. All of this is an allusion to the Christian Trinity.
  • The number three recurs several times in Tolkien's The Lord of the Rings and also in The Silmarillion. Three Rings of Power were given to the Elves. There are three Silmarils. The unions of the Eldar (Elves) and the Edain (Men) were three in number: Beren and Lúthien, Tuor and Idril, and (of course) Aragorn and Arwen.
  • Three Blind Mice is a children's nursery rhyme and musical round.
  • The Three Musketeers is a novel by Alexandre Dumas, and is part of a trilogy.
  • The Three Sisters is a play by Anton Chekhov.

In other fields

International maritime signal flag for 3 is known as a triband, a form of the tricolor.
Traveling in a troika (three-horse sled).
  • The French Revolution espoused three values (liberty, equality, fraternity).
  • The flags of many nations have three colors, including the flags of the United States, France, Colombia.
  • The number of stars in "Pacific's triple star" in the God Defend New Zealand, one of New Zealand's two national anthems.
  • The phrase "Third time's the charm" (or, rarely, "Three time's the charm") usually means that the third time a person attempts something, he or she will succeed.
  • Three-bean salad is an appetizer containing three types of beans, such as kidney, yellow, and green beans.
  • In most earlier video games, three lives were commonly given to players at the start.
  • The television VHF channel most often used for hooking up VCRs and/or video game systems. If it is otherwise occupied by a local broadcaster, then channel 4 is used instead.
  • On most phones, the 3 key is associated with the letters D, E, and F, but on the BlackBerry it is the key for U and I.
  • The number 3 is often used as a literary device to provoke a feeling of unnaturalness, as twos are much more common in nature (pairs of limbs, hemispheres, eyes, and so forth). This is a prevailing theme in Ray Bradbury's novel Fahrenheit 451. The aliens and their machines in the 2005 film War of the Worlds were associated with features recurring in threes: eyes, legs, fingers, and so on, for this reason.
  • A tricycle has three wheels.
  • Three Giza Pyramids: Khufu, Khafre, and Menkaure (Giza pyramid complex).

See also

Notes

  1. A natural number is any number that is a positive integer, such as 1, 2, 3, 4, and so forth. Often, the number 0 is also called a natural number.
  2. A cardinal number indicates the quantity of things, but not the order in which they occur. By contrast, ordinal numbers are first, second, third, and so on, indicating their positions in a series.
  3. A real number is a number that can be given by a finite or infinite decimal representation. The term "real number" was coined to distinguish it from an "imaginary number." The set of real numbers includes rational and irrational numbers, which can be positive, negative, or zero.
  4. Georges Ifrah, The Universal History of Numbers: From Prehistory to the Invention of the Computer (New York: Wiley, 2000, ISBN 0471393401), 393.
  5. The 3/4 time signature refers to three beats to a measure, with the quarter note comprising the beat.

References
ISBN links support NWE through referral fees

  • Flegg, Graham. Numbers: Their History and Meaning. Mineola, NY: Dover Publications, 2002. ISBN 0486421651.
  • Ifrah, Georges. The Universal History of Numbers: From Prehistory to the Invention of the Computer. Translated by David Bellos et al. New York: Wiley, 2000. ISBN 0471393401.
  • McLeish, John. The Story of Numbers: How Mathematics Has Shaped Civilization. New York: Fawcett Columbine, 1994. ISBN 0449909387.
  • Menninger, Karl. Number Words and Number Symbols: A Cultural History of Numbers. New York: Dover Publications, 1992. ISBN 0486270963.
  • Wells, D. G. The Penguin Dictionary of Curious and Interesting Numbers. London, UK: Penguin Books, 1998. ISBN 0140261494.

External links

All links retrieved June 13, 2023.

Credits

New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

The history of this article since it was imported to New World Encyclopedia:

Note: Some restrictions may apply to use of individual images which are separately licensed.