Full Idea
Examine wilful murder and see if you can find the matter of fact called vice. You only find certain passions, motives, volitions and thoughts. There is no matter of fact in the case. You can never find it till you turn your reflexion into your own breast.
Gist of Idea
We cannot discover vice by studying a wilful murder; that only arises from our own feelings
Source
David Hume (Treatise of Human Nature [1739], III.I.2), quoted by Philippa Foot - Hume on Moral Judgement p.77
Book Reference
Foot,Philippa: 'Virtues and Vices' [Blackwell 1981], p.77
A Reaction
[...In you breast you find 'disapprobation'] The question Foot asks is whether the facts of the case are relevant to the disapprobation. If they are not, as Hume implies, then it would be rational to feel the same disapprobation about drinking coffee.