"The old humility of the shepherds who felt themselves subject to the influences of Pleiades is no longer appropriate in the scientific world. But there is a danger lest it should be replaced by a species of arrogance towards nature, which can lead to great disasters. Man, however scientific he may be, is not omnipotent. He is hedged in by natural limits. By means of his knowledge and technique he can diminish the narrowness of these limits, but he can never remove them wholly. Some astronomers try to cheer us up in moments of depression by assuring us that one fine day the sun will explode, and in the twinkling of an eye we shall all be turned into gas. I do not know whether this is going to happen, nor when it will happen if it does happen, but I think it is safe to say that if it does it will be a matter outside human control, and that even the best astronomers will be unable to prevent it. This is an extreme example, and one which it is useless to think about, because there is no way in which human behavior can be adapted to it. It does, however, serve one purpose, which is to remind us that we are not gods."