"It takes time, see. You finish painting the painting and then you turn it to the wall. I mean, you say, does it have it or doesn't it have it? If it doesn't have it, you throw it away, but if you think it has it, you turn it to the wall. And then when you have made some more work, then you turn them all over. And you, again, try to see exactly what it does mean and just exactly how effectively you have rendered this meaning."