Classical economics is widely regarded as the first modern school of economic thought. Coming at a time when Mercantilism held sway, emphasizing the maximizing of exports and minimizing imports, classical economists promoted a radically different approach. They essentially regarded the economy as able to maintain its own equilibrium through market forces, and that government intervention in the form of artificial tariffs or other barriers that disrupted the free flow of goods and services were harmful to the economy. This view greatly impacted policies for a long time.
Classical economics was a major intellectual achievement. While new techniques of analysis were required to address new questions, giving rise to the mathematical formulations of the neoclassicals and others, and advances in technology and changes in social awareness appear to have transformed the economic landscape, economic theory today still rests in many areas, monetary and trade theory to name but two, upon the foundations laid by classical economists.
While the classical economists were not opposed to Capitalism, Karl Marx took key points from their theory and developed his exploitation theory. Marx's socialist economics greatly impacted the world, generally with disastrous results despite his intentions to free the general populace from Capitalist and government oppression. An understanding of economics that embraces all people, promoting a society of peace, harmony, and prosperity for all is perhaps what Marx hoped for. However, neither his adaptation of classical theory, nor classical economics in its original form has achieved this. It is not better mathematics that is needed to realize such a goal, but a deeper understanding of the true nature of human beings.