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

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.

Is my understanding only blindness to my own lack of understanding? It often seems so to me.

If in life we are surrounded by death, so too in the health of our intellect by madness.

Think of the tools in a tool-box: there is a hammer, pliers, a saw, a screwdriver, a rule, a glue-pot, nails and screws.--The function of words are as diverse as the functions of these objects.

The object of philosophy is the logical clarification of thought.

'Imagine a person whose memory could not retain what the word 'pain' meant-so that he constantly called different things by that name-but nevertheless used the word in a way fitting in with the usual symptoms and presuppositions of pain'-in short he uses it as we all do. Here I should like to say: a wheel that can be turned though nothing else moves with it, is not part of the mechanism.