The so-called law of induction cannot possibly be a law of logic, since it is obviously a proposition with a sense.--Nor, therefore, can it be an a priori law.

The object of philosophy is the logical clarification of thought.

Whereof one cannot speak, thereof one must be silent.

It would strike me as ridiculous to want to doubt the existence of Napoleon; but if someone doubted the existence of the earth 150years ago, perhaps I should be more willing to listen, for now he is doubting our whole system of evidence.

Uttering a word is like striking a note on the keyboard of the imagination.

Only when one thinks even much more madly than the philosophers can one solve their problems.

Here the term 'language-game' is meant to bring into prominence the fact that the speaking of language is part of an activity, of a form of life.