Full Idea
There are reasons for action, and we must discover them instead of deriving them from our preexisting motives - and in that way we can acquire new motives superior to the old.
Gist of Idea
We find new motives by discovering reasons for action different from our preexisting motives
Source
Thomas Nagel (The View from Nowhere [1986], VIII.1)
Book Reference
Nagel,Thomas: 'The View from Nowhere' [OUP 1989], p.139