We still celebrate, at a distance of centuries, the return of the birthday of great men. In reality it is a mistake. We ought to celebrate the hour when not merely life, but _the idea of their life_, quickened them. That is the really important birth that calls for commemoration. Luther’s real birthday was when he nailed his theses to the church door. Then was born the Luther that belongs to the world. Over the world-cradle of Columbus shines, not the trivial and evanescent planet given in his horoscope, but the little red flickering star of Guanahani, the light that he saw from the shore on the night before he landed on an island of the New World. Life is a voyage of discovery to the man who passes through it. He looks out with his child-eyes and discovers the world—at the bottom, discovers only himself. But one day a greater veil is torn from before his self. Genius, the greater I, stirs within him like the butterfly in its narrow pupa-case. For the world at large that is the hour when the _great_ man is born who will leave his mark on it. Haeckel’s biography only begins on a certain day, if we look at it rightly and broadly. Until that day he is merely a young man, an outgrowth from a rich old civilisation: a young man who has felt in him a struggle between artistic and scientific tendencies, like so many: who has vacillated between the choice of a “paying profession” and research for its own sake, and has decided for the former, like so many: who has chosen zoology, and begun to work hard on professional lines at his science: and who has been told prophetically that he will one day do something, though along a line where much has been done already. In the whole of this development we have as yet no indication of the real tenor of his life. It comes first with the name of Darwin. The arabesque of a very different life begins to blend with that of his own.