It is evident that the position to-day is rather different. It has become different since the War. It is probable, as we shall see later, that the War itself is partly responsible for the increased attention paid by the artist to science. But the influence was not direct. The artist was not transported with admiration for the men who could make poison-gas,[1] although he may have been more inclined to believe their philosophy that existence is meaningless. No, the change was, I believe, due to Einstein: in this respect he must be likened to Newton and Darwin. The fact that his theory is completely unintelligible to the enormous majority of those who take an interest in it is not at all to its disadvantage. Rather the contrary. The artist is attracted by the theory, and respectful to it, not in the least because he understands it, but because he feels it is the result of a most unusual and most powerful _imaginative_ effort. It gives him a new conception of the power of the human consciousness. This theory, he is convinced, has come from the heights. It is probable, as a matter of fact, he thinks this because he believes the theory to be about that mathematical platitude, a fourth dimension. The fourth dimension is a phrase to which imaginative people respond with quite extraordinary intensity. Its popularity is like that of giant telescopes, as was proved when a thousand pounds was recently offered for a simple explanation of it. It seems to be the phrase which, to the non-mathematician, is most pregnant with the vast and liberating unknown. If its meaning is ever generally understood, we may anticipate that interest in Einstein’s theory will decline. This will be a pity, because the popular reaction to Einstein’s theory is perfectly justified. It _is_ the most profound and original scientific theory that has ever been invented, and it displays a kind of imagination almost[2] unprecedented in the history of science. The feeling of the artist about it is right――it is vastly important to him. [1] He ought to have been. See _Callinicus_, by J. B. S. Haldane.