Whereof one cannot speak, thereof one must be silent.

Philosophy is not a theory but an activity.

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.

There are remarks that sow and remarks that reap.

The eternal life is given to those who live in the present.

This procedure [selecting the simplest law], however, has no logical justification but only a psychological one.

If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty.