This scientific term signifies no more than “the same thing.” It might be correctly, translated by “sameness.” This subject is of considerably more interest than may be imagined. All agree that the guilty person only ought to be punished — the individual perpetrator, and no other. But a man fifty years of age is not in reality the same individual as the man of twenty; he retains no longer any of the parts which then formed his body; and if he has lost the memory of past events, it is certain that there is nothing left to unite his actual existence to an existence which to him is lost.

I am the same person only by the consciousness of what I have been combined with that of what I am; I have no consciousness of my past being but through memory; memory alone, therefore, establishes the identity, the sameness of my person.

We may, in truth, be naturally and aptly resembled to a river, all whose waters pass away in perpetual change and flow. It is the same river as to its bed, its banks, its source, its mouth, everything, in short, that is not itself; but changing every moment its waters, which constitute its very being, it has no identity; there is no sameness belonging to the river.

Were there another Xerxes like him who lashed the Hellespont for disobedience, and ordered for it a pair of handcuffs; and were the son of this Xerxes to be drowned in the Euphrates, and the father desirous of punishing that river for the death of his son, the Euphrates might very reasonably say in its vindication: “Blame the waves that were rolling on at the time your son was bathing; those waves belong not to me, and form no part of me; they have passed on to the Persian Gulf; a part is mixed with the salt water of that sea, and another part, exhaled in vapor, has been impelled by a south-east wind to Gaul, and been incorporated with endives and lettuces, which the Gauls have since used in their salads; seize the culprit where you can find him.”

It is the same with a tree, a branch of which broken by the wind might have fractured the skull of your great grandfather. It is no longer the same tree; all its parts have given way to others. The branch which killed your great grandfather is no part of this tree; it exists no longer.

It has been asked, then, how a man, who has totally lost his memory before his death, and whose members have been changed into other substances, can be punished for his faults or rewarded for his virtues when he is no longer himself? I have read in a well known book the following question and answer:

“Question. How can I be either rewarded or punished when I shall no longer exist; when there will be nothing remaining of that which constituted my person? It is only by means of memory that I am always myself; after my death, a miracle will be necessary to restore it to me — to enable me to re-enter upon my lost existence.

“Answer. That is just as much as to say that if a prince had put to death his whole family, in order to reign himself, and if he had tyrannized over his subjects with the most wanton cruelty, he would be exempted fr............