Thought is necessary to go from here to there, to function technologically, to operate, to write a letter, to talk. There thought is absolutely necessary. The more objective, the more clear, the more reasonable, healthy, sane, the better. But thought also breeds pain, fear and sorrow. So what is one to do? At one level, thought is necessary, and at another level, or at the same level, thought operates, bringing agony. So there is a contradiction. Thought says, ‘If I could have no pain, no sorrow, no fear, then there will be ecstasy, I will live in perpetual heaven.’ So it invents a heaven. And the hell is this world.