Full Idea
Thoughts are merely signs, as words are signs for thoughts.
Gist of Idea
Thoughts are signs (just as words are)
Source
Friedrich Nietzsche (Unpublished Notebooks 1881-82 [1882], 5[1]272)
A Reaction
The obvious question he invites is 'signs of what?'. His point must be that most thinking is both non-verbal and non-conscious, which he took to be true even of intellectual thought. I sympathise with his view.
Book Reference
Nietzsche,Friedrich: 'The Joyful Science, and 1881-82 fragments (v 6)', ed/tr. Del Caro,Adrian [Stanford 2023], p.196