People often say that aesthetics is a branch of psychology. The idea is that once we are more advanced-all the mysteries of art-will be understood by psychological experiments. Exceedingly stupid at this idea is, this is roughly it.

An inner process stands in need of outward criteria.

Sometimes, in doing philosophy, one just wants to utter an inarticulate sound.

One can defend common sense against the attacks of philosophers only by solving their puzzles, i.e., by curing them of the temptation to attack common sense.

Philosophy hasn't made any progress? - If somebody scratches the spot where he has an itch, do we have to see some progress? Isn't genuine scratching otherwise, or genuine itching itching? And can't this reaction to an irritation continue in the same way for a long time before a cure for the itching is discovered?

Language disguises thought.

Propositions show what they say: tautologies and contradictions show that they say nothing.