From the earliest period of his history down to the present day man has ever been an object of eager study to himself. Nevertheless it is questionable whether he has yet succeeded in satisfying himself what he really is. “Everything by turns, and nothing long,” seems to be the conclusion to which one may most safely come after consideration of the numerous definitions which man has at different times seriously given of himself. He has likened himself to most things on earth, and to not a few under the earth. He has, as it were, dissolved himself, tested, precipitated, dried, and weighed himself; he has frequently lost himself, gone in search of himself, traced himself back to an homunculus, and forward to his final disappearance in a general dissolution of his constituent particles. But after making all these and many other experiments upon himself, whether he is the godlike son of Heaven, or an idealised monkey, he has not yet decided.