History of Ethics

Any historical overview is necessarily selective. The current article elaborates the central teachings of some of the most important ethical philosophers of the ancient, medieval and modern periods. Roughly speaking, ancient ethical thinking begins with the Greek Sophists of the fifth century B.C.E. and ends with the fall of Rome. Medieval philosophy is the philosophy of Western Europe from about AD 400-1400, approximately the period between the fall of Rome and the Renaissance. Modern Philosophy begins after the Renaissance (circa 1600) and continues until the present day.


Each period has its framework of thought shaped by accepted beliefs, trends, and presuppositions. It forms a background of ethical theories and it often remains as implicit knowledge. History of Ethics depicts changes of this background as well as particular ethical theories of each philosopher. The article covers ethical theories in Western philosophy alone. Rich resources in other traditions are not discussed.

Ancient Ethics

Ancient Greek ethics: Socrates, Plato, and Aristotle

In the western intellectual tradition, philosophical reflection on ethical codes began with the Greek Sophists of the fifth century B.C.E. The sophists were itinerant teachers who travelled around the Hellenic world teaching young men the art of public speaking—the most important skill needed to become successful in the political arena of the day. One of the earliest sophists, Protagoras, denied the existence of objective moral truth and defended a version of moral relativism. He emphasised the extent to which moral codes are human creations, sets of customs practiced and upheld by particular communities. In Plato’s Theaetetus, he is said have claimed that “whatever the city establishes as just, is just for that city as long as it judges so.” (Theaetetus 177d)

Later figures such as Callicles drew a contrast between moral laws as human conventions (nomos) and laws of nature (phusis—nature). In Plato’s Gorgias, Callicles argues that conventional moral codes are the inventions of a weak majority so as to subordinate the powerful few. Weak men promote belief in the goodness of equality since this is the best they can attain. But these conventions serve only to subvert the laws of natural justice in which “might is right.” It is a law of nature that the strong ought to possess more than the weak. Consequently, the right way for a strong man to live is to pursue his own interests and power, acting unjustly if he can get away with it. This challenge to the rationality of moral action may be seen as providing fuel for the philosophical thought of Socrates, Plato, and Aristotle. Theirs is a question that still haunts philosophical ethics more than two and a half thousand years later: Why be moral?

Much of Socrates’ activity as a philosopher consisted in examining people about virtue (arête). In Plato’s earlier dialogues, he is presented as enquiring into the essence of such traits as wisdom, courage and piety. Socrates was convinced that possessing and exercising the virtues are absolutely crucial if a person is to lead a good and happy (eudaimon) life. The point of philosophical inquiry into the virtues is that acting correctly requires that one possess knowledge of the human good. Indeed, Socrates seems to have held that the virtues of self-control, wisdom, and courage are nothing other than a particular type of knowledge. This idea—that terms such as courage and self-control pick out a single state of knowledge—has become known as the doctrine of the unity of the virtues. Given the unity of the virtues, it follows that a person cannot possess one virtue independently of the others: if he possesses one, he must possess them all. Both Plato, in the Republic, and Aristotle in Nicomachean Ethics subscribe to variations of this idea.

Plato’s greatest work, the Republic, is addressed specifically to the moral sceptic—someone who denies that being just is ultimately in one’s good, and hence who maintains that a person has no ultimate reason to behave justly beyond the conventional sanctions of society. In other words, the sceptic claims that a person has no reason to behave justly when he can get away with behaving unjustly. Plato’s response to the sceptic is that justice is an ordered state of the soul with each part—reason, spirit and appetite—performing its proper function. The just person is happy because his soul is in ordered in the proper way. By contrast, the unjust person’s soul is chaotic and at war with itself, so that even if he were able to satisfy his desires, a lack of inner harmony and unity prevent the attainment of happiness. In this way, being moral is argued to be ultimately in a person’s own self-interest. Possession of virtue—most specifically justice—is an indispensibly necessary condition for a good life.

Aristotle was a student of Plato, and his ethical inquiries are conducted within the same ethical framework. Aristotle’s basic thought is that happiness (eudaimonia)—living well—depends on a creature’s perfecting its natural endowments. He argues that reason is unique to man so that the function (ergon) of a human being will involve the exercise and perfection of its rational capacities. It follows that the good life for man involves the attainment of virtue or excellence (arête) in reason. Aristotle divides the human excellences (' 'aretai—often translated as ‘virtues’) connected with reason into two groups: moral and intellectual excellence. (He also recognises bodily excellence (virtue) but this is exclusively non-rational and so does not contribute to a distinctively human (rather than animal) good.) Moral excellences are excellences of character and pertain to action, including dispositions to feel emotions (such as fear) and make certain types of choices. Intellectual excellences (virtues) are excellences of thought including such states as wisdom and intelligence. In general, his claim is that the virtues of character and intellect are ways of perfecting reason and hence indispensable to the good human life. However, although Aristotle emphasizes the importance of cultivating one’s rational capacities, he does not neglect the importance of friends, wealth, and social status in a good life. He says that one is unlikely to be happy if one lacks certain external goods such as ‘good birth, good children, and beauty’. So, a person who is extremely ugly, or has “lost children or good friends through death” (1099b5-6), or who is all alone, is unlikely to be happy. Virtue does not guarantee a happy life.

Later Greek ethics: Epicureanism and Stoicism

Later Greek ethical thought is conducted within the same Platonic/Aristotelian framework. It is generally agreed that happiness (eudaimonia) is the ultimate human good, and living a good life will involve cultivating and exercising virtues. Epicurus departs from Plato and Aristotle in that his view of eudaimonia is hedonistic. He identifies the eudaimon life with the life of pleasure, understanding eudaimonia as a more or less continuous experience of the pleasure, and also, freedom from pain and distress (ataraxia). But Epicurus does not advocate that one pursue any and every pleasure. Rather, he recommends a policy whereby pleasures are optimized in the long run. Some pleasures are not worth having because they lead to greater pains, and some pains are worthwhile when they lead to greater pleasures. The best strategy for attaining a maximal amount of pleasure overall is not to seek instant gratification but to work out a sensible long term policy.

Epicurus argues that the life of pleasure will coincide with the life of virtue. He believes that we do and ought to seek virtue because virtue brings pleasure. His basic doctrine is that a life of virtue is the life which generates the most amount of pleasure, and it is for this reason that we ought to be virtuous. This thesis—the happy life (eudaimonia) is the pleasurable life—is not a tautology as “the happy life is the good life” would be: rather, it is the substantive and controversial claim that a life of pleasure and absence of pain is what happiness consists in.

Stoic philosophy begins with Zeno of Citium and was further developed by Cleanthes and Chrysippus. A basic assumption of Stoic thinking is that the universe itself is governed by laws of reason, and structured in the best possible way. This metaphysical thesis is connected with the ethical view that the good life is one that is lived in accordance with reason. Moral goodness and happiness are attained by mirroring the perfect rationality of the world in oneself and by finding out and living one’s own assigned role in the cosmic order of things.

Medieval Ethics

Church Fathers

One central philosophical aim of the patristic period—the writings of the Church fathers—was the attempt to understand and interpret the Judeo-Christian scriptures in light of the Greek philosophers. Saint Augustine was undoubtedly the most important figure of the time. (Other significant figures are Gregory of Nyassa, Ambrose, Saint Jerome, and Boethius.) Augustine’s major contribution to ethics is his account of the will (voluntas; see voluntarism). Indeed, some philosophers (e.g., Albrecht Dihle (1982)) have argued that the modern and medieval concept of the will originates in Augustine.

Ancient Greek ethics is a form of intellectualism: the intellect was conceived as the most important faculty in the determination of action. Once the practical intellect had judged a certain course of action to be the best, rational choice would follow. Indeed, Socrates, and in more guarded fashion, Aristotle, denied the possibility of akrasia or weakness of will. All cases of wrongdoing are treated as cases of imperfect knowledge, encapsulated in the famous Socratic formula: “no one does wrong willingly.” In contrast, Saint Augustine held that one might know the good and still not do it. In a famous passage from Confessions II, he recounts how as a boy he stole pears for the very thrill of doing wrong. This is a challenge to Greek intellectualism in that Augustine did not think that stealing the pears was good, or that the pears themselves were particularly good—he had better ones at home. To make sense of this possibility Augustine develops a notion of the will as an executive power than need not follow the intellect’s judgments. A person can perform an action that he judges to be entirely unjustified. It is always open to the will to reject the judgments of the intellect. The will is capable of choosing to do something the intellect judges to be bad.

Scholasticism: Aquinas, Scotus, and Ockham

The age of high scholasticism begins towards the end of the eleventh century and ends around the middle of the fourteenth century. The thirteenth century was a particularly fruitful period of philosophical activity. The main contributors were members of religious orders such as the Dominicans and the Franciscans—central figures were Saint Thomas Aquinas, John Duns Scotus, and William of Ockham. Thomas Aquinas developed and extended Aristotle’s ethical theory into a Christian context. Aquinas inherits the Greek framework of ethics, which is a eudaimonistic account of the human good, and a focus on the virtues rather than discrete actions. As discussed in the previous section, ancient philosophers agreed that happiness (eudaimonia) is the highest human good—the goal of human existence—and that virtue (arête) is in some way essential for one’s achieving this goal. Aquinas’ adaptation of this idea amounts to his identifying God—the exemplification of perfect goodness—as the goal of human life. Eudaimonia is transposed into perfect happiness (beatitude) conceived as union with God. For Aquinas, then, the goal of human life is fully achieved in the beatific vision, identified as supernatural union with God in the after life.

The second basic assumption Aquinas inherits from Aristotle is the importance of the virtues in perfecting the rational nature of man, and hence their crucial significance in achieving eudaimonia. Here again Aquinas transposes Aristotle’s largely naturalistic theory into a theological context. Aristotle held that the cultivation and exercise of intellectual and moral virtues are the most important components in a good human life. But this conception of a good life is largely that of a biological organism living according to its distinctive endowments. Therefore, given Aquinas’ departure from Aristotle on the final goal of human life, that is, his identifying man’s ultimate end with supernatural union with God, he is required to give some explanation of the relationship between the perfection of man’s natural powers, and his achieving perfect happiness in a supernatural afterlife. To fill this gap, Aquinas introduces the theological virtues of faith, hope, and love, which have God as their immediate object. According to Aquinas, non-Christians cannot display theological virtues, although they can manifest other non-theological virtues such as courage. Therefore, while heathens are capable of eudaimonia in Aristotle’s sense, they are not capable of beatitude, which requires the theological virtues. One important difference between the ‘natural virtues’ and the theological virtues is that the former are within the agent’s power to cultivate and develop. On Aristotle’s analysis, which Aquinas adopts, character virtues such as courage are developed through training. By contrast, theological virtues depend on God’s help in the form of divine grace. Faith, hope, and love not acquired through voluntary actions but are directly infused by God. (Aquinas’ discussion of the virtues is found in Summa Theologiae IaIIae (49-88) and throughout IIaIIae.)

Aquinas’ ethical theory has been extraordinarily influential, especially as it has shaped the ethical teachings of the Catholic Church. He is generally regarded as one of the most sophisticated developers of natural law ethics. In the medieval period, philosophers contrasted natural law (ius naturale)—moral principles that do not derive from human legislation—with positive law (ius positivum), that is, law created by human authorities. The notion of natural law was developed in a variety of ways but on one important account, natural laws are patterns of conduct that facilitate the fulfillment of man’s natural developmental trajectory. Natural law is a participation in the eternal law (ST IaIIae 91, 2), where the eternal law refers to rational plan by which all creation is ordered (ST IaIIae 91, 1). Underpinning this conception of natural law is then a teleological conception of the universe according to which each individual part plays a role in the structure of the whole. On a second view, natural law is again contrasted with the laws of human governments but is now understood as directly dependent on God’s status as lawgiver. On this conception, natural law refers to laws made by God and revealed to mankind via the presentation of the Ten Commandments to Moses, by means of revelation, and the exercise of human conscience.

Thomas Aquinas offers a synthesis of these two conceptions of natural law. He argues that the commandments revealed to Moses are essentially the same as those that could be comprehended by human reason on the basis of knowledge of human nature. For example, adultery is wrong because it violates natural law in the sense that it thwarts or prevents the natural good of human beings. The law revealed to Moses that one must refrain from adultery is simply an additional source of the same basic truth. God’s laws as revealed to mankind are not in conflict with natural law in first sense. They are a supplementary source of prescriptions of courses of action that allow human beings to achieve their proper development.

In contrast with Aquinas, John Duns Scotus, and to a greater degree, William of Ockham, incline towards the second conception of natural law in which human law and morality are directly dependent on God’s capacity as a lawgiver. According to Ockham, natural law is ultimately rooted in the will of God. This idea has become known as theological voluntarism, a meta-ethical doctrine according to which actions are right in virtue of God’s willing them. For example, children should honor their parents because God wills that they do so. (Divine Command Theories of ethics are species of theological voluntarism.) Ockham argues for theological voluntarism as follows. Since God is omnipotent he can do anything logically possible. This means that while God cannot create a married bachelor, he can make it the case that killing is morally right. For the statement that killing is morally right may be false but it is not contradictory. Ockham reasons that God would be capable of making killing morally right only if right and wrong depend on his will. Therefore, since God is capable of making killing morally right it follows that God’s will is the ultimate source of moral requirements.

Theological voluntarism is often thought subject to a fatal difficulty called the "Euthyphro Problem." In Plato’s Dialogue, Euthyphro defines holiness as follows: “I would say that the holy is what all the gods love, and that the opposite, what all the gods hate, is unholy.” In response, Socrates inquires: “Is what is holy loved by the gods because it is holy, or is it holy because it is loved?” (10a). This question might be reformulated in terms of right action, goodness, or any normative other property. For example, are right actions right because God commands them, or does God command them because they’re right? For example, is it that promise-keeping is right because God commands it, or does God deem promise-keeping right because it is right—God knows that it is right? In the former case, God makes things right—there is no independent standard of rightness, independent of what God wills. This first possibility is the essence of Theological Voluntarism—moral right is a produce of the divine will. In the latter case, there is an independent standard of rightness, a standard that God knows and in virtue of which he makes his commands. The dilemma is that both of these alternatives are problematic for theological voluntarism. Either God’s commands are arbitrary because he could equally have commanded that promise keeping is wrong, or the rightness of promise-keeping is independent of God’s will.

Ockham was the last great philosopher of the period of high scholasticism. In the century after his death, the European intellectual world was transformed. The beginning of the Renaissance (1400), and the Protestant Reformation (1520) brought about dramatic changes in the intellectual climate of the day. Many philosophers attempted to disassociate themselves from the philosophical traditions of medieval scholasticism that they conceived to be artefacts of an old world order. In this way, the modern period was born. (For more on the significant philosophers of the Renaissance period, see, e.g., Francisco Suarez and Thomas More.)

Modern Ethics

For Aquinas, human beings have God as their ultimate goal, and natural laws are those patterns that facilitate their achieving this end. These laws are for the benefit of everyone whether they know it or not. By contrast, modern natural law affirms the right of individual human beings to determine their own purposes. Hugo Grotius (1583-1645) is an important figure in the mediation and transformation of the natural law theories of the medieval period into an Enlightenment context. He argued that natural law does not depend on God’s existence but on rational human nature, and that it is the function of political society to protect the natural rights of human beings—rights every person has independently of any contribution he or she makes to the community.

Thomas Hobbes

Thomas Hobbes provoked widespread reaction when he argued in his masterpiece, Leviathan (1651), that there is no ultimate or objective good. Good and evil are naturally relative to people’s appetites so that they comes to regard what they are inclined to pursue as good and what they are inclined to avoid as bad. Good and bad are relative to individuals’ desires and preferences: there is no such thing as objective goodness. This implies that there are many different goods for different people and not one overarching good as Aristotle and Aquinas had maintained.

Hobbes defended a version of psychological egoism, the idea that man’s nature is selfish and that he seeks primarily for the satisfaction of his own desires. As a result, Hobbes offers a pessimistic account of the state of nature, a notion that social contract theorists (compare Jean-Jacques Rousseau and John Locke) used to indicate the condition of human beings without or prior to government. Hobbes characterizes the state of nature as an utterly lawless state of affairs in which “the notions of right and wrong, justice and injustice … have no place,” and where each man has the right to do whatever he deems necessary to preserve himself. With each person striving for his or her own desires to be satisfied, and with a general equality of natural powers so that no one substantially supercedes anyone else in natural endowments such as strength, people live in unceasing conflict with one another. Such a condition, Hobbes says, is “called war; and such a war as is of every man against every other man.” He observes that under such conditions the “life of man is solitary poor, nasty, brutish and short.” Since it is to everyone’s benefit that this condition of war be ended, a result a social contract is drawn up in which each person agrees to restrict his own freedom for peace so long as everyone else is willing to do the same. Power is transferred to some political authority that is able to enforce the details of the contract. Morality is thus ultimately a function of political power. We see then in Hobbes that man is ultimately the creator of morality through the creation of political institutions.

Hobbes claims both that human nature is inherently selfish, and that the notion of objective moral principles without political authority is misconceived. Both of these positions were challenged. Firstly, Hobbes’s psychological egoism came under heavy attack by the Earl of Shaftsbury and Francis Hutcheson. Shaftsbury, for instance, argues that human beings are capable of altruism, since they have desires for their own good and for that of others (“private good” and “public good”). Secondly, in response to Hobbes’ subjective account of value, intuitionists such as Samuel Clarke, Ralph Cudworth, and Richard Price argue that the basic principles of morality are independent of both God’s will and of political institutions. Human beings know these moral rules by rational intuition analogous to the manner in which they come to know the basic principles of mathematics. Similarly, the moral sense theorists such as Francis Hutcheson argued for the existence of a human capacity to perceive moral qualities of good and evil. The perceptual notion of a moral sense stands in contrast with Clarke’s appeals to rational insight.

David Hume

The great Scottish philosopher, David Hume continued the work of Shaftsbury and Hutcheson, developing an account of ethics that is based on feeling rather than reason. Hume rejects rationalist theories of natural law, accusing them of an ‘is-ought’ fallacy, an error that arises from supposing that premises about what is the case (matters of fact) can justify conclusions about what one ought to do (see fact and value). Moreover, Hume contends that reason is motivationally inert: “Reason is and ought to be the slave of the passions, and can never pretend to any other office than to serve and obey them” (Treatise, II, ii, 3). Since morality is connected with action, if reason is motivationally inert, it follows that morality must be fundamentally a matter of feeling rather than reason. Hume emphasizes the emotion of sympathy, which is a reaction occasioned in one living creature by distress in another. Sympathy makes the well being of one person a concern to others. Hume argues that it is because of their natural sympathy that human beings come to regard certain states as virtues, more particularly, those states that are useful to their possessors (e.g., courage), and that are useful to others (e.g., justice).

The seeds of utilitarianism lie in the writings of Hume, who emphasizes the ‘utility’ of virtues. But by far the most important developers and proponents of utilitarianism are Jeremy Bentham (1748 –1832) and John Stuart Mill (1806- 1873). Utilitarianism recognizes one fundamental moral principle—the principle of utility. In Bentham’s formulation it is as follows: “By the Principle of Utility is meant that principle which approves or disapproves of every action whatsoever, according to the tendency which it appears to have … to promote or to oppose that happiness.” Similarly, in Mill’s formulation, Utilitarianism “the creed which accepts as the foundation of morals, Utility, or the Greatest Happiness Principle, holds that actions are right in proportion as they tend to promote happiness; wrong as they tend to produce the reverse of happiness.” For utilitarianism, morality is about increasing the amount of happiness in the world. Both Bentham and Mill equated happiness with pleasure and in this sense both were hedonists. Bentham believed any particular pleasure or pain has a determinate value, which can be measured, and compared. He attempted to construct a scale of comparison and measurement of pain and pleasure. He called this scale the felicific calculus. He claimed that the value of a pleasure is to be determined by such factors as its duration and its intensity. Bentham’s hedonism may be labeled quantitative hedonism, since all pleasures and pains appear on the same scale, being measured according to the same set of criteria (such as duration and intensity). In contrast with Bentham for whom all pleasures were alike and comparable, Mill distinguished between higher and lower pleasures. “…Some pleasures are more desirable and more valuable than others. It would be absurd that while, in estimating all other things, quality is considered as well as quantity, the estimation of pleasures should be supposed to depend on quantity alone.” Higher pleasures include pleasures of the human mind: pleasures of the intellect, imagination, appreciation of beauty, and others. According to Mill, these higher pleasures are vastly superior to lower pleasures of the body or “mere sensations” They are different in quality, not just quantity. The hedonism in classical utilitarianism has been widely criticized since Mill’s time, but its basic idea—that morality is about increasing the amount of good in the world—has remained attractive. Utilitarianism has undergone substantial refinements, notably by Henry Sidgwick, and has continues to be one of the dominant moral theories up until the present day.

Immanuel Kant

Kant’s ethical philosophy stands in stark contrast with Utilitarianism. Kant does not agree with the utilitarianism that happiness is unconditionally good; indeed, he suggests that happiness achieved through immorality is not a good thing at all. Rather, he argues, the ‘good will’ is the only unconditional good, that is, the only thing that is good in all circumstances. In rough, a good will is a motivation to do the right action because it is the right. Being motivated in this way is to be motivated by duty. The ‘good will’ is good not because of what it brings about—again in contrast with utilitarianism—but in virtue of its own principle of willing.

Kant’s notion of the good will leads him to the Categorical Imperative. The Categorical Imperative is the central concept in Kant’s ethics. It refers to the “supreme principle of morality” [4: 392], from which all our moral duties are derived. The basic principle of morality is an imperative because it commands certain courses of action. It is a categorical imperative because it commands unconditionally, quite independently of the particular ends and desires of the moral agent. Kant formulates the Categorical Imperative in several different ways but according to the well-known ‘Universal Law’ formulation, you should ‘act only according to that maxim by which you can at the same time will that it be a universal law’. Since maxims are, roughly, principles of action, the Categorical Imperative commands that one should act only on universalizable principles, principles that could be adopted by all rational agents.

Kant provided several formulations of the Categorical Imperative and claimed that they were all equivalent. According to the well known humanity formula one should “act in such a way that you always treat humanity, whether in your own person or in the person of any other, never simply as a means, but always at the same time as an end.” [Gr. 66-67/429] The Humanity formula is closely linked with the idea of respecting persons. This formula expresses one of Kant’s deepest disagreements with utilitarianism, which does not place any limitation on what it is permissible to do to a person: anything is permitted, so long as the consequences are good enough. For example, it may be required that one torture a person in order to promote overall happiness. In contrast, Kant argues that human beings are ends in themselves, which means that they have value that is intrinsic, absolute, incomparable, and objective. Kant argues that every human agent possesses this sort of ultimate value, and gives it a special name: dignity. When Kant says that human beings are ends in themselves, he means that they have dignity and the appropriate response to dignity is respect. The Humanity Formula of the Categorical Imperative prescribes, then, that we respect persons because they possess dignity. We do so by treating persons as ends in themselves, that is, treat them in ways which acknowledge their fundamental value. The amounts to a strict prohibition on forms of action that will treat them as mere objects with conditional value.

G.W.F. Hegel

G.W.F. Hegel (1770-1831) was one of the first and most influential of Kant’s critics. He claimed that the categorical imperative was formal and empty because any maxim could be willed as a universal law. Once this is recognized, he argues, it evident that he content of morality only come from actual human institutions and practices. So Hegel emphasizes the social aspect of moral lives, the extent to which moral codes are drawn from the ethical institutions of the family, civil society, and the state. Hegel’s understanding of morality in terms of actual human practices invites questions about whether morality is universally binding, or, as Protagoras had maintained two thousand years previously, simply a reflection of a given society’s cultural practices. Echoing Callicles’ attack on Protagorean conventional morality, Friedrich Nietzsche (1844-1900) attacked the notion of universal morality, and the possibility of any abstract rational principle governing action (such as the Categorical Imperative). He emphasized the psychological forces underpinning different moral codes, and their contingent historical developments.


Nietzsche’s criticism of conventional moral codes revolves around his notion of slave morality. Slave morality, which corresponds closely to the Judeo-Christian moral code with its focus on duty and self-sacrifice, says Nietzsche, originates in the resentment of the weak and oppressed. Slaves morality is a subversion of master morality—the natural states of the strong—in which noble and life affirming values have been transformed in vices, and the contrary, slavish and life-negating values, transformed in values. Slave morality is the outcome of weak people’s coming to regard the qualities of the naturally strong as evil, and transforming their own resentment into current conceptions of morality, which have greatly debilitated human life. (See Beyond Good and Evil, sects 60-8; Genealogy of morals, First essay.)

Analytic philosophy

In the analytic tradition, twentieth century ethics has been preoccupied with the nature and meaning of ethical judgments. In this sense, the twentieth century has focused tremendously on meta-ethics rather than normative ethics. This meta-ethical agenda was set, firstly, by G. E. Moore’s tremendously influential work Principia Ethica, and secondly, by the influence of logical positivism. In Principia Ethica, Moore argues against naturalistic ethical theories that attempt to identify goodness with some natural property such as being pleasurable or being desired. (He claims to find this line of reasoning in the writing of Bentham and Mill). According to his open question argument, any attempted definition of a moral property such as goodness in terms of natural properties must fail. For example, suppose someone defined goodness, a normative property, in terms of “being desired,” a descriptive property, and went on to make the claim that war is desired. Moore’s point is that it would make perfect sense—the question is open—for someone to retort “sure, war is desired, but is it good?” Moore holds that this question would not make sense if good really meant ‘is desired’ (or so the argument goes). For instance, it makes no sense—the question is closed—to ask whether Charles is unmarried upon learning that he is a bachelor. This is because bachelor does mean unmarried man.

Moore himself concluded that goodness was a simple non-natural property that was indefinable and known through intuition. Although a majority of philosophers were convinced by Moore’s open question argument, they regarded his intuitionism as unacceptable. They took the open question argument to show not that goodness was simple and indefinable but that it is not a descriptive property at all. In other words, they endorsed the fact-value distinction. One way of dividing facts from values is in terms of a distinction between descriptive language, which aims to state facts, and evaluative language, which evaluates people, objects, actions, etc, as ‘good’, ‘bad’, ‘right’ and ‘wrong’. For example, the sentence “roses are red” is descriptive; it represents the world as being a certain way and may be evaluated as true or false. By contrast, the sentence “kindness is good” is an evaluation. Proponents of the fact-value distinction argue that the former descriptive sentence (“roses are red”) may describe a true state of affairs—state a fact—whereas the latter (“kindness is good”) does not.

Another historically important argument for the fact-value distinction comes from logical positivism. The logical positivists embraced a theory of the linguistic meaning called the principle of verification. This principle says that a sentence is strictly meaningful only if it expresses something that can be confirmed or disconfirmed by empirical observation. For example, the sentence “there are possums in India” is meaningful because it could be verified or falsified by actually checking whether there are possums in India. One significant implication of the principle of verification is that evaluative judgments are strictly meaningless. The sentence “murder is wrong” cannot be confirmed or disconfirmed by empirical experience. We may find that people believe that murder is wrong, or disapprove of murder, but there is nothing in world corresponding to ‘wrongness’ that could be investigated by empirical science. Therefore, according to the logical positivists, all evaluative judgments are meaningless and so they do not state facts.

Emotivism and prescriptivism may be understood as attempts to make sense of evaluative language while adhering to the principle of verification. If all evaluative judgments are meaningless, then what are people doing when they say that kindness is good, or that cruelty is bad? Emotivists such as A.J. Ayer, and C.L. Stevenson, hold that evaluations express the speaker’s feelings and attitudes: saying that kindness is good is a way of expressing one’s approval of kindness. Similarly, R.M Hare argues that evaluations are prescriptions (commands): saying that kindness is good is a way of telling people that they should be kind. Evaluative judgments are then understood as emotive or prescriptive, and are contrasted with descriptive judgments. Descriptive judgments are appraisable as true or false; evaluative judgments are not. In this way, a fact-value distinction is upheld.

Existentialist Ethics

While analytic philosophy was preoccupied by linguistic concerns, continental philosophy underwent an existentialist turn. Existentialist ethics, originating in the work of Kierkegaard, Heidegger, and developed in the twentieth century by Jean-Paul Sartre, has at its centre a doctrine of radical human freedom and responsibility. In Sartre’s well-known slogan, ‘man is condemned to be free’. The existentialists typically argued from an assumption of radical freedom to the conclusion that values are subjective rather than objective: they are ultimately created by free choice. Each person must make a personal decision about morality, and strive to live an authentic life, by facing up to their responsibility, thereby avoiding bad faith. Existentialists hold that the scope of personal responsibility is much larger than ordinarily supposed: according to Sartre, for instance, human beings are responsible for their characters, emotional reactions, and even to some extent the situations they find themselves in.

In the latter half of the twentieth century ethics has developed in a number of different directions. After the long dominance of utilitarianism, Kantian ethics and virtue ethics have undergone a widespread revival.

John Rawls and others

John Rawls’ magisterial A Theory of Justice especially has sparked interest in Kant’s ethical and political thinking. Rawls’ theory is inspired by Kant’s fourth formulation of the Categorical Imperative. The Kingdom of Ends formulation of the CI states that we must “act in accordance with the maxims of a member giving universal laws for a merely possible kingdom of ends” (4:439). Rawls interprets this in terms of a social contract theory. His idea is that principles of justice are based on the notion of a hypothetical contract to which reasonable individuals would agree from a position in which substantive facts about the good are not known. In this way Rawls argues that the priority of rules of justice over may be justified independently of utilitarian concerns with the good.

Interest in the concept of virtue and ancient ethical theory more generally has increased largely as a result of work by Philippa Foot, Alistair MacIntryre, Bernard Williams, and Elizabeth Anscombe. Anscombe’s article “Modern Moral Philosophy,” for instance, argues that duty-based conceptions of morality are incoherent for they are based on the idea of a “law but without a lawgiver.” Her point is that a system of morality conceived along the lines of the Ten Commandments, as a system of rules for action, depends on someone having actually made these rules. However, in the modern climate, which is unwilling to accept that morality depends on God in this way, a rule-based conception of morality is stripped of its metaphysical foundation. Anscombe recommends a return the virtue ethical theories of the ancients, particularly Aristotle, which ground morality in the interests and well being of human moral agents (eudaimonia), and can do so without appeal to any questionable metaphysic.

In the closing years of the twentieth century and beginning of the twenty-first there has been an increased interest in applied ethics. A great deal of work continues be done on abortion, environmental ethics, just war, medical treatment, business ethics, animal rights, and roles of women (see feminism).


Ancient ethics

Primary Sources

  • Aristotle, The Nichomachean Ethics, Translated by Martin Oswald. New York: The Bobs-Merrill Company, 1962.
  • Aristotle, The Complete Works of Aristotle, vol. 1 and 2, Jonathan Barnes, ed. Princeton: Princeton University Press, 1984. ISBN 0691099502
  • Cicero, De Finibus Bonorum et Malorum. H. Rackham, trans. London: W. Heinemann; New York: The Macmillan Co., 1914.
  • Cicero, On Moral Ends, tr. by R. Woolf. Cambridge: Cambridge University Press, 2001. ISBN 0511040601
  • Epicurus, Letter to Menoeceus, Principal Doctrines. and Vatican Sayings,28-40 in B. Inwood and L. Gerson, Hellenistic Philosophy: An Introduction, Second Edition. Indianapolis: Hackett Publishing Co., 1997.
  • Plato, Plato's Complete Works. John M. Cooper, ed. Indianapolis: Hackett Publishing Co., 1997. ISBN 0872203492
  • Long, A.A., and D.N. Sedley, The Hellenistic Philosophers, vol 1 and 2 Cambridge: Cambridge University Press, 1987. ISBN 0521255619

Secondary sources

  • Annas, J. An Introduction to Plato’s Republic. Oxford: Clarendon Press; New York : Oxford University Press, 1981. ISBN 0198274289
  • Broadie, S. Ethics with Aristotle. New York: Oxford University Press, 1991. ISBN 0195066014
  • Gulley, N. The philosophy of Socrates. London; Melbourne: Macmillan; New York: St. Martin's Press, 1968.
  • Irwin, T. Plato’s Moral Theory: The early and Middle dialogues. Oxford; New York: Clarendon Press, 1977. ISBN 019824567X
  • Kerferd, G.B. The Sophistic Movement. Cambridge; New York: Cambridge University Press, 1981. ISBN 0521239362
  • Rist, J.M. Epicurus: An introduction. Cambridge [Eng.] University Press, 1972. ISBN 0521084261
  • Urmson, J. O. Aristotle’s Ethics. Blackwell Publishers, 1988. ISBN 0631159460
  • Vlastos, G. Plato. A Collection of Critical Essays. New York: Anchor Books, 1971.

Medieval Ethics

Primary Sources

  • Abelard, P. Ethics, trans. and ed. D. Luscombe. Oxford: Clarendon Press, 1971.
  • Anslem. Basic Writings, trans. S.N. Deane. La Salle, Ill.: Open Court Pub. Co., 1962.
  • Aquinas, T. Summa theologiae, ed. T. Gilbey. Cambridge University Press, 2006. ISBN 0521029090
  • Augustine. The Essential Augustine, ed., V.J. Bourke. New York: Mentor Omega, 1964.
  • Augustine. The Confessions, ed., E.B. Pusey. London: Dent, 1962.
  • Duns Scotus. God and Creatures; The Quodlibetal Questions, ed., F. Alluntius and A. Wolter. Princeton: Princeton University Press 1975. ISBN 0691071950
  • Duns Scotus, John. Duns Scotus on the Will and Morality, ed. Allan Wolter; William A Frank. Washington, DC: Catholic University of America Press, 1997. ISBN 0813208955
  • Suarez, F. De Legibus. Oxford: Oxford University Press 1944.
  • William of Ockham. "Quodlibeta septem" (Quodlibetal Questions), in Opera Theologica. St Bonaventure, NY: The Franciscan Institute, vol. IX; trans. A.J. Freddoso and F.E. Kelley, New Haven, CT: Yale University Press, 1991, 2 vols.
  • William of Ockham. Philosophical Writings, ed. P. Boehner. Indianapolis: Bobbs-Merrill 1977.

Secondary Sources

  • Adams, M. William Ockham. Notre Dame, IN: University of Notre Dame Press, 1987. ISBN 0268019401
  • Adams, M. "William Ockham: Voluntarist or Naturalist?" in J. Wippel (ed.) Studies in Medieval Philosophy. Washington, DC: Catholic University Press, 1987. ISBN 0813206405 *Coplestone, F.C. A History of Medieval Philosophy. New York: Harper & Row, 1972. ISBN 0061360732
  • Crowe, M. B. The Changing Profile of the Natural Law. The Hague: Nijhoff, 1977. ISBN 9789024719921
  • Finnis, John. Natural Law and Natural Rights. Oxford: Clarendon Press; New York: Oxford University Press, 1980. ISBN 0198760981
  • Finnis, John. "Is Natural Law Theory Compatible with Limited Government?" in Robert P. George(ed.) Natural Law, Liberalism, and Morality. Oxford: Clarendon Press ; New York: Oxford University Press, 1996. ISBN 0198259840
  • Finnis, John. Aquinas: Moral, Political, and Legal Theory. New York: Oxford University Press, 1998. ISBN 0585134936
  • Freppert, L. The Basis of Morality According to William Ockham. Chicago, Ill.: Franciscan Herald Press, 1988. ISBN 0819909181
  • Haakonssen, Knud. "Natural Law Theory," in Lawrence C. Becker and Charlotte B. Becker (ed.) Encyclopedia of Ethics. New York: Garland, 1992. ISBN 081530403X
  • Haakonssen, Knud. Natural Law and Moral Philosophy: From Grotius to the Scottish Enlightenment. New York, NY, USA: Cambridge University Press, 1996. ISBN 0521496861
  • Idziak, J.M. Divine Command Morality: Historical and Contemporary Readings. New York: Edwin Mellen Press, 1980. ISBN 0889469695
  • King, P. "Ockham’s Ethical Theory," in P. Spade (ed.) The Cambridge Companion to Ockham. Cambridge, UK; New York: Cambridge University Press, 1999. ISBN 052158244X
  • Kent, B. Virtues of the Will: The Transformation of Ethics in the Late Thirteenth Century. Washington, DC: Catholic University of America Press, 1995. ISBN 0813208297
  • Murphy, Mark C. Natural Law and Practical Rationality. Cambridge, UK; New York: Cambridge University Press, 2001. ISBN 0521802296

Modern moral philosophy

  • Anscombe, G.E.M. "Modern Moral Philosophy," in Philosophy 33 (1958).
  • Bentham, J. Introduction to the Principles of Morals and Legislation. Oxford: Basic Blackwell, 1789.
  • Foot, P. Virtues and Vices and other essays in moral philosophy. Berkeley: University of California Press, 1978. ISBN 0520036867
  • Foot, P. Natural Goodness. Oxford: Clarendon; New York : Oxford University Press, 2001. ISBN 0198235089
  • Grotius, H. The Law of War and Peace three books, trans. Kelsey et al. Oxford: Clarendon Press, 1925.
  • Hegel, G.W.F. Philosophy of Right, trans. Knox. Oxford: Clarendon Press, 1942.
  • Hobbes, T. Leviathan. Oxford: Oxford University Press, 1998. ISBN 0585193282
  • Hume, D. "An Enquiry Concerning the Principles of Morals," in Enquiries Concerning Human Understanding and Concerning the Principles of Morals. L.A. Selby-Bigge (ed.), revised by P.H. Nidditch. Oxford: Clarendon Press, 1975. ISBN 0198245351
  • Hume, D. Treatise of Human Nature, L.A. Selby-Bigge (ed.), revised by P.H. Nidditch. Oxford: Clarendon Press; New York: Oxford University Press, 1978. ISBN 0198245874
  • Kant, I. Practical Philosophy, ed. and trans. M.J. Gregor with introduction by A.W, Wood. Cambridge: Cambridge University Press, 1999. ISBN 0521654084
  • Locke, J. Two Treatises of Government, Peter Laslett (ed.) Cambridge; New York: Cambridge University Press, 1988. ISBN 052135448X
  • MacIntyre, A. After Virtue. Notre Dame, Ind.: University of Notre Dame Press, 1981. ISBN 026800594X
  • Mill, J.S. "Utilitarianism," in Collected works of John Stuart Mill, Vol. 10, J.M. Robson(ed.) Toronto: Univ. of Toronto Press, 1973. ISBN 0802018750
  • Moore, G.E. Principia Ethica. Cambridge, At the University press, 1903.
  • Nietzsche, F. On the Genealogy of Morals, Walter Kaufmann (ed.), Walter Kaufmann and R.J. Hollingdale (trans.) New York: Vintage Books, 1989. ISBN 0679724621
  • Rachels, J. The Elements of Moral Philosophy. Philadelphia: Temple University Press, 1986. ISBN 0877224056
  • Rawls, J. A theory of Justice. Cambridge, Mass., Belknap Press of Harvard University Press, 1971. ISBN 0674880102
  • Sartre, Jean Paul. Existentialism is Humanism. P Mairet (trans.) London; Methuen, 1974. ISBN 041331300X
  • Anthony Ashley Cooper Shaftesbury. "An Inquiry concerning virtue or merit." in Characteristics, ed. J.M Robertson. Manchester Univ. Press, 1977. ISBN 9780719006579
  • Sidgwick, H. The Methods of Ethics.'. Chicago: University of Chicago Press, 1962.
  • Williams, B. Ethics and the Limits of Philosophy. Cambridge, MA: Harvard University Press, 1985. ISBN 0674268571

External links

All links retrieved October 7, 2013.

General Philosophy Sources


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