“…sense of futility that comes from doing anything merely to prove to yourself that you can do it: having a child, climbing a mountain, making some sexual conquest, committing suicide.The marathon is a form of demonstrative suicide, suicide as advertising: it is running to show you are capable of getting every last drop of energy out of yourself, to prove it… to prove what? That you are capable of finishing. Graffiti carry the same message. They simply say: I’m so-and-so and I exist! They are free publicity for existence.Do we continually have to prove to ourselves that we exist? A strange sign of weakness, harbinger of a new fanaticism for a faceless performance, endlessly self-evident.”

“If there are no self-evident first principles, as a foundation for reasoning to conclusions that are not immediately apparent, how can you construct any kind of a philosophy? If you have to prove even the basic axioms of your metaphysics, you will never have a metaphysics, because you will never have any strict proof of anything, for your first proof will involve you in an infinite regress, proving that you are proving what you are proving and so on, into the exterior darkness where there is wailing and gnashing of teeth. If Descartes thought it was necessary to prove his own existence by the fact that he was thinking, and that his though therefore existed in some subject, how did he prove that he was thinking in the first place? But as to the second step, that God must exist because Descartes had a clear idea of him – that never convinced me, then or at any other time, or now either. There are much better proofs for the existence of God than that one.”

“How do you prove we exist? Maybe we don't.”

“We have to dare to be ourselves, however frightening or strange that self may prove to be.”

“... what we say or do is unimportant; it is merely semblance, beyond which our real life lies concealed... We know this better than we can prove, but in order to prove it we have to express it, and on the path to speech the essential somehow gets lost.”

“You can't prove that something doesn't exist. You can only prove that something does exist.”