Full Idea
I want to say, baldly, that there is no criterion for practical rationality that is not derived from that of goodness of will.
Gist of Idea
All criterions of practical rationality derive from goodness of will
Source
Philippa Foot (Natural Goodness [2001], 1)
Book Reference
Foot,Philippa: 'Natural Goodness' [OUP 2003], p.11
A Reaction
Where does that put the successful and clever criminal? Presumably they are broadly irrational, but narrowly rational - but that is not very clear distinction. She says Kant's concept of the good will is too pure, and unrelated to human good.
Related Ideas
Idea 23693 Practical rationality must weigh both what is morally and what is non-morally required [Foot]
Idea 18238 Only a good will can give man's being, and hence the world, a final purpose [Kant]