Full Idea
In her early work she also defends moral rationalism, which is the idea that morality gives reasons for action to everyone, even those who lack the desire to do what is right.
Gist of Idea
Morality gives everyone reasons to act, irrespective of their desires
Source
report of Philippa Foot (Moral Beliefs [1959]) by John Hacker-Wright - Philippa Foot's Moral Thought Intro
Book Reference
Hacker-Wright,John: 'Philippa Foot's Moral Thought' [Bloomsbury 2013], p.5
A Reaction
Evidently a rejection of the Humean view that only a desire can motivate action, including moral action. There is an ongoing debate about whether reasons can cause anything, or motivate anything. I think the contents of reasons pull us towards action.
Related Ideas
Idea 23683 Moral norms are objective, connected to facts about human goods [Foot, by Hacker-Wright]
Idea 23685 Reason is not a motivator of morality [Foot, by Hacker-Wright]