Adam Smith's 'invisible hand' appears only once in The Wealth of Nations

Smith used the phrase just a single time in his 1776 masterwork, to make a narrow point about merchants preferring to invest at home. It was later generalised by economists, especially after Paul Samuelson's 1948 textbook, into the now-famous idea that individuals pursuing their own self-interest can unintentionally benefit society as a whole.

— Adam Smith, An Inquiry into the Nature and Causes of the Wealth of Nations — 1776
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