What we cannot speak about we must pass over in silence.
All I know is what I have words for.
The subject does not belong to the world; rather, it is a limit of the world.
Don't get involved in partial problems, but always take flight to where there is a free view over the whole single great problem, even if this view is still not a clear one.
A new word is like a fresh seed sown on the ground of the discussion.
When we can't think for ourselves, we can always quote