You complain of my letter because I argue a philosophical proposition in it while pleading for love. Do you not know that this is man's way? And I would not try to deceive you: this philosophical proposition, which seems to you almost a matter of indifference, is more to me than everything else in the world. For it I could surrender all my heart's hope; for it I could sacrifice my own person; even, if the choice were necessary, which cannot be, I might sacrifice you. There is this duality in man's nature. The ambition of his intellect, the passion, it may be, to force upon the world some vision of his imagination or some theorem of his brain, works in him side by side with his personal being, and the two are never quite fused. Can you not recall a score of examples in history of men who have led this dual existence? You reviewed for me Bismarck's Love Letters and were yourself struck by this sharp contrast between the iron determination of the man in public affairs and the softness and sweetness of his domestic life. That is but one case in point of the eternal dualism in masculine nature which a woman can never comprehend, and which always, if it confronts her nakedly, she resents. For a woman is not so. There exists no such gap in her between her heart and brain, between her outer and inner life. And the consequence shows itself in many ways. She is less efficient in the world and is never a creator or impresser of new ideas; but, on the other hand, her character possesses a certain unity that is the wonder of all men who observe. She calls the man selfish and is bitter against him at times, but her accusation is wrong. It is not selfishness which leads a man if needs be to cut off his own personal desires while sacrificing another; it is the power in him which impels the world into new courses. A man's virtues are aggressive and turned toward outer conquest and may have little relation to his own heart. But a woman's virtues are bound up with every impulse of her personal being; they work out in her a loveliness and unity of character which make the man appear beside her coarse and unmoral. Men of vicious private life have more than once been benefactors of the human race; I think that never happened in the case of a woman.