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.

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.

What Copernicus really achieved was not the discovery of a true theory but of a fertile new point of view.

Language disguises thought.

Most of the propositions and questions to be found in philosophical works are not false but nonsensical.

A picture is a model of reality.

With my full philosophical rucksack I can only climb slowly up the mountain of mathematics.