It is easy to give proofs. Only brutalised criminals and insane persons take absolutely no interest in their fellow men; they live as if they were alone in the world, and the presence of strangers has no effect on them. But for him who possesses a self there is a self in his neighbour, and only the man who has lost the logical and ethical centre of his being behaves to a second man as if the latter were not a man and had no personality of his own. “I” and “thou” are complementary terms. A man soonest gains consciousness of himself when he is with other men. This is why a man is prouder in the presence of other men than when he is alone, whilst it is in his hours of solitude that his self-confidence is damped. Lastly, he who destroys himself destroys at the same time the whole universe, and he who murders another commits the greatest crime because he murders himself in his victim. Absolute selfishness is, in practice, a horror, which should rather be called nihilism; if there is no “thou,” there is certainly no “I,” and that would mean there is nothing. There is in the psychological disposition of the man of genius that which makes it impossible to use other men as a means to an end. And this is it: he who feels his own personality, feels it also in others. For him the Tat-tvam-asi is no beautiful hypothesis, but a reality. The highest individualism is the highest universalism. Ernest Mach is in great error when he denies the subject, and thinks it is only after the renunciation of the individual “I” that an ethical relation, which excludes neglect of the strange “I” and over-estimation of the individual “I,” may be expected. It has already been seen where the want of one’s own I leads in relation to one’s neighbour. The I is the fundamental ground of all social morality. I should never be able to place myself, as an actual psychological being, in an ethical relation to a mere bundle of elements. It is possible to imagine such a relationship; but it is entirely opposed to practical conduct; because it eliminates the psychological condition necessary for making the moral idea an actual reality. We are preparing for a real ethical relation to our fellow men when we make them conscious that each of them possesses a higher self, a soul, and that they must realise the souls in others. This relation is, however, manifested in the most curious manner in the man of genius. No one suffers so much as he with the people, and, therefore, for the people, with whom he lives. For, in a certain sense, it is certainly only “by suffering” that a man knows. If compassion is not itself clear, abstractly conceivable or visibly symbolic knowledge, it is, at any rate, the strongest impulse for the acquisition of knowledge. It is only by suffering that the genius understands men. And the genius suffers most because he suffers with and in each and all; but he suffers most through his understanding.