A French politician once wrote that it was a peculiarity of the French language that in it words occur in the order in which one thinks them.

If a lion could talk, we could not understand him.

I am sitting with a philosopher in the garden; he says again and again 'I know that that’s a tree', pointing to a tree that is near us. Someone else arrives and hears this, and I tell him: 'This fellow isn’t insane. We are only doing philosophy.

Suppose someone follows the series "1,3,5,7, ..", and in writing the series 2x+1; and he asked himself "But am I always doing the same thing, or something different every time?" If from one day to the next someone promises: "Tomorrow I will give up smoking", does he say the same thing every day, or every day something different?

With my full philosophical rucksack I can only climb slowly up the mountain of mathematics.

One can defend common sense against the attacks of philosophers only by solving their puzzles, i.e., by curing them of the temptation to attack common sense.

The depressed man lives in a depressed world.