Would replacing bodily organs with artificial substitutes preserve the identity of the person?

SELF is that conscious thinking thing,—whatever substance made up of, (whether spiritual or material, simple or compounded, it matters not)—which is sensible or conscious of pleasure and pain, capable of happiness or misery, and so is concerned for itself, as far as that consciousness extends. Thus every one finds that, whilst comprehended under that consciousness, the little finger is as much a part of himself as what is most so. Upon separation of this little finger, should this consciousness go along with the little finger, and leave the rest of the body, it is evident the little finger would be the person, the same person; and self then would have nothing to do with the rest of the body.

A part of a person is a manifest absurdity. When a man loses his estate, his health, his strength, he is still the same person, and has lost nothing of his personality. If he has a leg or an arm cut off, he is the same person he was before. The amputated member is no part of his person, otherwise it would have a right to a part of his estate, and be liable for a part of his engagements. It would be entitled to a share of his merit and demerit, which is manifestly absurd. A person is something indivisible, and is what Leibnitz calls a monad. My personal identity, therefore, implies the continued existence of that indivisible thing which I call myself. Whatever this self may be, it is something which thinks, and deliberates, and resolves, and acts, and suffers. I am not thought, I am not action, I am not feeling ; I am something that thinks, and acts, and suffers. My thoughts, and actions, and feelings, change every moment ; they have no continued, but a successive, existence ; but that self or I, to which they belong, is permanent, and has the same relation to all the succeeding thoughts, actions, and feelings which I call mine.

Sooner or later some eminent physiologist will have his neck broken in a super-civilized accident or find his body cells worn beyond capacity for repair. He will then be forced to decide whether to abandon his body or his life. After all it is brain that counts, and to have a brain suffused by fresh and correctly prescribed blood is to be alive — to think. The experiment is not impossible; it has already been performed on a dog and that is three-quarters of the way towards achieving it with a human subject. But only a Brahmin philosopher would care to exist as an isolated brain, perpetually centred on its own meditations. Permanently to break off all communications with the world is as good as to be dead. However, the channels of communication are ready to hand. Already we know the essential electrical nature of nerve impulses ; it is a matter of delicate surgery to attach nerves permanently to apparatus which will either send messages to the nerves or receive them. And the brain thus connected up continues an existence, purely mental and with very different delights from those of the body, but even now perhaps preferable to complete extinction.

Finally, after consummating his desires and having his efforts crowned with success, he placed the brain within the head of a machine. The brain was brought to consciousness. The creature's body was discarded after the all-important brain had been removed. … As Professor Jameson came to, he became aware of a strange feeling. He was sick. The doctors had not expected him to live; they had frankly told him so--but he had cared little in view of the long, happy years stretched out behind him. Perhaps he was not to die yet. He wondered how long he had slept. How strange he felt--as if he had no body. Why couldn't he open his eyes? He tried very hard. A mist swam before him. His eyes had been open all the time but he had not seen before. That was queer, he ruminated. All was silent about his bedside. Had all the doctors and nurses left him to sleep--or to die?

A change in any considerable part of a body destroys its identity; but it is remarkable, that where the change is produced gradually and insensibly we are less apt to ascribe to it the same effect. The reason can plainly be no other, than that the mind, in following the successive changes of the body, feels an easy passage from the surveying its condition in one moment to the viewing of it in another, and at no particular time perceives any interruption in its actions. From which continued perception, it ascribes a continued existence and identity to the object. But whatever precaution we may use in introducing the changes gradually, and making them proportionable to the whole, it is certain, that where the changes are at last observed to become considerable, we make a scruple of ascribing identity to such different objects. There is, however, another artifice, by which we may induce the imagination to advance a step farther; and that is, by producing a reference of the parts to each other, and a combination to some common end or purpose. A ship, of which a considerable part has been changed by frequent reparations, is still considered as the same; nor does the difference of the materials hinder us from ascribing an identity to it. The common end, in which the parts conspire, is the same under all their variations, and affords an easy transition of the imagination from one situation of the body to another.

“Strange you shouldn’t know me, though, isn’t it? Pompey, bring me that leg!” Here Pompey handed the bundle a very capital cork leg, all ready already dressed, which it screwed on in a trice, and then it stood upright before my eyes. Devil the word could I say. “And a bloody action it was ,” continued the thing, as if in a soliloquy; “but then one musn’t fight with the Bugaboos and Kickapoos, and think of coming off with a mere scratch. Pompey, I’ll thank you now for that arm. Thomas (turning to me) is decidedly the best hand at a cork leg; he lives in Race street, No. 79 — stop, I’ll give you his card; but if you should ever want an arm, my dear fellow, you must really let me recommend you to Bishop.” Here Pompey screwed on an arm. … “O yes, by the by, my eye — here, Pompey, you scamp, screw it in! Those Kickapoos are not so very slow at a gouge — but he's a belied man, that Dr. Williams, after all; you can’t imagine how well I see with the eyes of his make.” I now began very clearly to perceive that the object before me was nothing more or less than my new acquaintance, Brevet Brigadier General John A. B. C. Smith. The manipulations of Pompey had made, I must confess, a very striking difference in the appearance of the personal man.