Full Idea
The end of all moral speculations is to teach us our duty.
Gist of Idea
Moral philosophy aims to show us our duty
Source
David Hume (Enquiry concerning Principles of Morals [1751], I.136)
Book Reference
Hume,David: 'Enquiries Conc. Human Understanding, Morals', ed/tr. Selby-Bigge/Nidditch [OUP 1975], p.172
A Reaction
A surprising view from someone who thinks morals are basically sentiment.