It is so characteristic, that just when the mechanics of reproduction are so vastly improved, there are fewer and fewer people who know how the music should be played.

Don't for heaven's sake, be afraid of talking nonsense! But you must pay attention to your nonsense.

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.

Nothing is so difficult as not deceiving oneself.

Think of words as instruments characterized by their use, and then think of the use of a hammer, the use of a chisel, the use of a square, of a glue pot, and of the glue.

I might say: if the place I want to get to could only be reached by way of a ladder, I would give up trying to get there. For the place I really have to get to is a place I must already be at now. Anything that I might reach by climbing a ladder does not interest me.

Logic must look after itself. In a certain sense, we cannot make mistakes in logic.