All I know is what I have words for.

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.

For an answer which cannot be expressed the question too cannot be expressed. The riddle does not exist. If a question can be put at all, then it can also be answered.

If we spoke a different language, we would perceive a somewhat different world.

It is an hypothesis that the sun will rise tomorrow: and this means that we do not know whether it will rise.

Where two principles really do meet which cannot be reconciled with one another, then each man declares the other a fool and a heretic

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.