Just be indipendent of the external world, so you don't have to fear for what's in it.

If we were to imagine an orange on the blue side or green on the red side or violet on the yellow side, it would give us the same impression as a north wind coming from the southwest.

What signs fail to express, their application shows. What signs slur over, their application says clearly.

Philosophy aims at the logical clarification of thoughts. Philosophy is not a body of doctrine but an activity. A philosophical work consists essentially of elucidations.

The aspects of a thing that are most important to us are hidden to us because of their simplicity and familiarity.

A new word is like a fresh seed sown on the ground of the discussion.

Only describe, don't explain.