When the caterpillar emerges from the egg, almost all that was inside the egg has become caterpillar; the shell is nearly empty, and cannot move; therefore we do not count it, and call the caterpillar a continuation of the egg’s existence, and personally identical with the egg. So with the chrysalis and the moth; but after the moth has laid her eggs she can still move her wings about, and she looks nearly as large as she did before she laid them; besides, she may yet lay a few more, therefore we do not consider the moth’s life as continued in the life of her eggs, but rather in their husk, which we still call the moth, and which we say dies in a day or two, and there is an end of it. Moreover, if we hold the moth’s life to be continued in that of her eggs, we shall be forced to admit her to be personally identical with each single egg, and, hence, each egg to be identical with every other egg, as far as the past, and community of memories, are concerned; and it is not easy at first to break the spell which words have cast around us, and to feel that one person may become many persons, and that many different persons may be practically one and the same person, as far as their past experience is concerned; and again, that two or more persons may unite and become one person, with the memories and experiences of both, though this has been actually the case with every one of us. Our present way of looking at these matters is perfectly right and reasonable, so long as we bear in mind that it is a _façon de parler_, a sort of hieroglyphic which shall stand for the course of nature, but nothing more. Repair (as is now universally admitted by physiologists) is only a phase of reproduction, or rather reproduction and repair are only phases of the same power; and again, death and the ordinary daily waste of tissue, are phases of the same thing. As for identity it is determined in any true sense of the word, not by death alone, but by a combination of death and failure of issue, whether of mind or body.