From an 1971 interview with Henri Cartier-Bresson
But as for me, I enjoy shooting a picture. Being present. It’s a way of saying, “Yes! Yes! Yes!” It’s like the last three words of Joyce’s “Ulysses,” which is one of the most tremendous works which have ever been written. It’s “Yes, yes, yes.” And photography is like that. It’s yes, yes, yes. And there are no maybes. All the maybes should go to the trash, because it’s an instant, it’s a moment, it’s there! And it’s respect of it and tremendous enjoyment to say, “Yes!” Even if it’s something you hate. Yes! It’s an affirmation.
Read the full interview at: http://lens.blogs.nytimes.com/2013/06/21/cartier-bresson-there-are-no-maybes/