Full Idea
According to discourse ethics moral rightness is internally linked to validity and is analogous to truth: ..thus Habermas takes himself to have shown that morality is a matter of knowledge, rather than the expression of contingently held values.
Gist of Idea
Moral right is linked to validity and truth, so morality is a matter of knowledge, not an expression of values
Source
report of Jürgen Habermas (Moral Consciousness and Communicative Action [1990]) by James Gordon Finlayson - Habermas Ch.7:102
Book Reference
Finlayson,James G.: 'Habermas' [OUP 2005], p.102
A Reaction
I can immediately hear Nietzsche asking why you place such a high value on knowledge. Personally I don't assume that values must be 'contingent'. The Aristotelian tradition sees necessary values in facts about human nature.