Full Idea
Reason is our power of finding out true propositions.
Gist of Idea
Reason is our power of finding out true propositions
Source
Francis Hutcheson (Treatise 4: The Moral Sense [1728], §I)
Book Reference
'British Moralists 1650-1800 Vol. 1', ed/tr. Raphael,D.D. [Hackett 1991], p.307
A Reaction
This strikes me as a very good definition. I don't see how you can define reason without mentioning truth, and you can't believe in reason if you don't believe in truth. The concept of reason entails the concept of a good reason.