Full Idea
The 'thing in iself' acted on Kant's successors like a hole in the closed world of knowledge...Hegel, Fichte and Schelling wanted to penetrate into what they presumed to be the heart of things, by the invention of means of 'ego', or 'nature', or 'spirit.,
Gist of Idea
Hegel, Fichte and Schelling wanted to know Kant's thing-in-itself, as ego, or nature, or spirit
Source
Rüdiger Safranski (Nietzsche: a philosophical biography [2000], 07)
Book Reference
Safranski,Rüdiger: 'Nietzsche: a philosophical biography' [Granta 2003], p.164
A Reaction
[a bit compressed] Although no scientist claims to know the ultimate essence of matter, the authority of science largely comes from persuasively moving us several steps closer to the thing in itself (more persuasively than these three).
Related Ideas
Idea 21911 Fichte, Hegel and Schelling developed versions of Absolute Idealism [Lewis,PB]
Idea 21912 Fichte, Schelling and Hegel rejected transcendental idealism [Lewis,PB]