Logic is not a body of doctrine, but a mirror-image of the world. Logic is transcendental.

The child learns to believe a host of things. I.e. it learns to act according to these beliefs. Bit by bit there forms a system of what is believed, and in that system some things stand unshakeably fast and some are more or less liable to shift. What stands fast does so, not because it is intrinsically obvious or convincing; it is rather held fast by what lies around it.

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

If people did not sometimes do silly things, nothing intelligent would ever get done.

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

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.

Philosophy can be said to consist of three activities: to see the commonsense answer, to get yourself so deeply into the problem that the common sense answer is unbearable, and to get from that situation back to the commonsense answer.