The Theory of Moral Sentiments was written by Adam Smith in 1759. It provided the ethical, philosophical, psychological, and methodological underpinnings to Smith's later works, including The Wealth of Nations (1776), A Treatise on Public Opulence (1764) (first published in 1937), Essays on Philosophical Subjects (1795), and Lectures on Justice, Police, Revenue, and Arms (1763) (first published in 1896).
Broadly speaking, Smith followed the views of his mentor, Francis Hutcheson of the University of Glasgow, who divided moral philosophy into four parts: Ethics and Virtue; Private rights and Natural liberty; Familial rights (called Economics); and State and Individual rights (called Politics).
More specifically, Smith divided moral systems into:
- Categories of the nature of morality. These included Propriety, Prudence, and Benevolence.
- Categories of the motive of morality. These included Self-love, Reason, and Sentiment.
It was in the TMS that Smith first referred to the "invisible hand" to describe the apparent benefits to society of people behaving in their own interests. Smith writes (6th ed. p. 350):
... In spite of their natural selfishness and rapacity, though they mean only their own conveniency, though the sole end which they propose ... be the gratification of their own vain and insatiable desires, they divide with the poor the produce of all their improvements. They are led by an invisible hand to make nearly the same distribution of the necessaries of life, which would have been made, had the earth been divided into equal portions among all its inhabitants, and thus without intending it, without knowing it, advance the interest of the society.
How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it. Of this kind is pity or compassion, the emotion which we feel for the misery of others, when we either see it, or are made to conceive it in a very lively manner. That we often derive sorrow from the sorrow of others, is a matter of fact too obvious to require any instances to prove it; for this sentiment, like all the other original passions of human nature, is by no means confined to the virtuous and humane, though they perhaps may feel it with the most exquisite sensibility. The greatest ruffian, the most hardened violator of the laws of society, is not altogether without it.
Adam Smith (1723-1790) is commonly regarded as the first modern economist with the publication in 1776 of The Wealth of Nations. He wrote in a wide range of disciplines: moral philosophy, jurisprudence, rhetoric and literature, and the history of science. He was one of the leading figures in the Scottish Enlightenment. Smith also studied the social forces giving rise to competition, trade, and markets. While professor of logic, and later professor of moral philosophy at Glasgow University, he also had the opportunity to travel to France, where he met François Quesnay and the physiocrats; he had friends in business and the government, and drew broadly on his observations of life as well as careful statistical work summarizing his findings in tabular form. He is viewed as the founder of modern economic thought, and his work inspires economists to this day. The economic phrase for which he is most famous, the “invisible hand” of economic incentives, was only one of his many contributions to the modern-day teaching of economics.