Jeremy Bentham was extremely generous in his attributions of credit for the expression with which he is most associated. "Priestley was the first (unless it was Beccaria) who taught my lips to pronounce this sacred truth:- That the greatest happiness of the greatest number is the foundation of morals and legislation." [cf. Bentham's Commonplace Book in Works, vol. X, page 142.]
(1733 - 1804)
Joseph Priestley was a unitarian clergyman, scientist and political reformer. Bentham says he came across the phrase “greatest happiness of the greatest number” in one of Priestley’s pamphlets; but if so, the source has never been found. Bentham was certainly impressed by Priestley's The First Principles of Government and the Nature of Political, Civil and Religious Liberty (1768). Priestley states: "The good and happiness of the members, that is the majority of the members of the state, is the great standard by which every thing relating to that state must finally be determined."
Bentham also remarks that the origin of the phrase must ultimately be traced to the Italian jurist Cesare Beccaria. ["massima felicità divisa nel maggior numero"] Beccaria's Essay on Crimes and Punishments (1764) was translated into English in 1767. It is possible Beccaria himself derived the phrase from French-Swiss Enlightement philosopher Helvetius. Earlier still, moral sentiment theorist Francis Hutcheson (1694-1746) says "that Action is best, which procures the greatest Happiness for the greatest numbers; and that, worst, which, in like manner, occasions Misery.” (Inquiry into the Origins of our Ideas of Beauty and Virtue, in Two Treatises, 1725: Sect. 3.8). Indeed, prefiguring Bentham's "felicific calculus", Hutchinson proposes a "moral arithmetic" for calculating the best consequences of an action. But he did not systemetically explore the idea; and Bentham does not seem to have been directly influenced by Hutchinson.
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