Full Idea
Kant argues that the good will is unconditionally good because it is the only thing able to be a source of value.
Gist of Idea
The good will is unconditionally good, because it is the only possible source of value
Source
report of Immanuel Kant (Critique of Practical Reason [1788]) by Christine M. Korsgaard - Aristotle and Kant on the Source of Value 8 'Kant'
Book Reference
Korsgaard,Christine M.: 'Creating the Kingdom of Ends' [CUP 1996], p.240
A Reaction
The obvious worry is the circularity of resting a theory of value on identifying a 'good' will as its source.
Related Ideas
Idea 18675 Kant may rate two things as finally valuable: having a good will, and deserving happiness [Orsi on Kant]
Idea 1454 Morality is not about making ourselves happy, but about being worthy of happiness [Kant]