Full Idea
No knowledge can be its own foundation and proof. Every knowledge presupposes something still higher as its foundation, and this ascent has no end.
Gist of Idea
Knowledge can't be its own foundation; there has to be regress of higher and higher authorities
Source
Johann Fichte (The Vocation of Man [1800], 3.I)
Book Reference
Fichte,Johann G.: 'The Vocation of Man', ed/tr. Preuss,Peter [Hackett 1987], p.71
A Reaction
A metaphor that's hard to visualise! He must have in mind a priori as well as empirical knowledge. The 'higher' levels don't seem to be God, but some region of absolute rationality, to which free minds have access. I think.