Full Idea
In what consciousness affirms from within itself as being-in-itself or the True we have the standard which consciousness itself sets up by which to measure what it knows.
Gist of Idea
Consciousness derives its criterion of knowledge from direct knowledge of its own being
Source
Georg W.F.Hegel (Phenomenology of Spirit [1807], p.053), quoted by Stephen Houlgate - An Introduction to Hegel 03 'The Method'
Book Reference
Houlgate,Stephen: 'An Introduction to Hegel' [Blackwell 2005], p.53
A Reaction
This seems to be a very close relation of Descartes' 'clear and distinct conceptions'. This certainly places Hegel in the Rationalist camp.