The first edition in book-form of Mill's spirited defence of this controversial branch of ethics closely associated with Jeremy Bentham and the 'Greatest Happiness Principle'.

Mill had been exposed to utilitarianism at an early age by his father, the political economist James Mill, who was a close disciple of Bentham — as Mill recalled in his autobiography, published posthumously in 1873, the 'Benthamic standard of "the greatest happiness" was that which I had always been taught to apply' (Autobiography, p.64). That is, that 'actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness' (Utilitarianism, pp9-10).

Mill's own utilitarianism gradually took on a more rules-based character, the most recognisable of which was the harm principle that Mill introduced four-years earlier in his essay On Liberty. This declares that the 'only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others. His own good, either physical or moral, is not a sufficient warrant' (On Liberty, pp21-22).

Thus, even if a particular act of harming another individual might bring about an increase in happiness on a single occasion, it cannot be condoned by the set of rules which promotes the total greatest happiness of society as a whole.

First edition in book-form, first printing; 8vo (23 x 15 cm); 4pp publisher's ads to rear, the odd note in pencil to margins, ownership inscription in pen to front free endpaper verso, a little toned at perimeter of textblock; publisher's blind-panelled pebble-grain brown cloth, neatly rebacked, preserving the original spine laid down and gilt lettering but for the letter 'U' which is supplied in neat facsimile, uncut edges, very good; [4], 95, [1], 4[ads]pp.