"So we shouted at each other and shook the room; because metaphysics is the only thoroughly emotional thing"

On the day that I met the strange cabman I had been lunching in a little restaurant in Soho in company with three or four of my best friends. My best friends are all either bottomless sceptics or quite uncontrollable believers, so our discussion at luncheon turned upon the most ultimate and terrible ideas. And the whole argument worked out ultimately to this: that the question is whether a man can be certain of anything at all. I think he can be certain, for if (as I said to my friend, furiously brandishing an empty bottle) it is impossible intellectually to entertain certainty, what is this certainty which it is impossible to entertain? If I have never experienced such a thing as certainty I cannot even say that a thing is not certain. Similarly, if I have never experienced such a thing as green I cannot even say that my nose is not green. It may be as green as possible for all I know, if I have really no experience of greenness. So we shouted at each other and shook the room; because metaphysics is the only thoroughly emotional thing. And the difference between us was very deep, because it was a difference as to the object of the whole thing called broad-mindedness or the opening of the intellect. For my friend said that he opened his intellect as the sun opens the fans of a palm tree, opening for opening's sake, opening infinitely for ever. But I said that I opened my intellect as I opened my mouth, in order to shut it again on something solid. I was doing it at the moment. And as I truly pointed out, it would look uncommonly silly if I went on opening my mouth infinitely, for ever and ever.

-Tremendous Trifles (1909)