Always get rid of theory private object in this way: assume that it constantly changes, but that you do not notice the change because your memory constantly deceives you.

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

This sort of thing has got to be stopped. Bad philosophers are like slum landlords. It's my job to put them out of business.

Language disguises thought.

To understand a sentence means to understand a language. To understand a language means to be master of a technique.

A picture is a model of reality.

That which cannot be said must not be said. That which cannot be said, one must be silent thereof.