> How could you upload just your brain and be the same person? Need your whole body, surely?
In practice, people who received heart transplants are generally considered to be the same person as they had been before the transplantation, so it seems most of us have already accepted that you don't need the whole body.
"Three groups of patients could be identified: 79% stated that their personality had not changed at all postoperatively. In this group, patients showed masslve defense and denial reactions, mainly by rapidly changing the subject or making the question ridiculous. Fifteen per cent stated that their personality had indeed changed, but not because of the donor organ, but due to the life-threatening event. Six per cent (three patients) reported a distinct change of personality due to their new hearts."
https://link.springer.com/article/10.1007/BF00435634
Sure parts are replaceable, one at a time. Replacing them one a time maintains the body. The structure of the body is more than the sum of it's parts though.
The robots need a body to orient their brain in spacetime. AIs classifying images from pure theory requires a body to relate to all the other objects in the world. Tagging a door knob as 'turnable, openable' requires the robot to have a hand that can do it. A banana only looks edible and life sustaining because we have a body. A floating head loses all interest in a lot of things, I'd guess.
It hurts my brain to think about that. Simulating the brain is one idea, adding the body on too is levels of complexity I can't fathom. Biologists struggle writing 128 page documents just to characterize a single molecule, so they can construct a 5-6 part nano-vehicle.
The hubris of this idea is just so far off the charts I can't even call it wrong or insane. It's in the "FTL" bucket for me.
Um, in practice, the number of people who have actually received a head transplant is precisely zero. So how they are considered is about as relevant as how Harry Potter is considered.
> Um, in practice, the number of people who have actually received a head transplant is precisely zero. So how they are considered is about as relevant as how Harry Potter is considered.
In fairness, the context was uploading the brain, and whether the whole body was needed, so it was a semi-reasonable misread.
Still... there's a large distance from "I can have a heart transplant and still be considered the same person (even though 1% of my body now has different DNA)" to "I can have no body at all and still be the same person". The claim was that a body is a significant part of who we are as people, which is not a claim that a heart transplant addresses at all.
> [T]here's a large distance from "I can have a heart transplant and still be considered the same person (even though 1% of my body now has different DNA)" to "I can have no body at all and still be the same person". The claim was that a body is a significant part of who we are as people, which is not a claim that a heart transplant addresses at all.
All right, let's tackle it a bit more directly than replacement: Does amputation of a limb diminish an individual's personhood? Is your answer dependent on the use of a prosthetic?
I mean, I saw this guy who had both legs amputated. He entered the Utah Summer Games in the 100 meters in the "open" class, meaning he was taking on the best in the state straight up - no "handicapped" class. He took first in the preliminaries and second in the final.
If he thinks of himself as an athlete, he still is. But if he wants to play footsie under the table with his SO... that's something he lost.
So it depends to some degree on where your sense of personhood is. But I think for all of us, we're not a brain in a vat. We interact with our external physical environment. If you lose all of that... haven't you lost something that matters to you? If you can't enjoy a steak, can't enjoy a kiss, and can't enjoy the smell of a flower (or even the sight of one), then aren't you something less than you were when you could do all those things?
In practice, people who received heart transplants are generally considered to be the same person as they had been before the transplantation, so it seems most of us have already accepted that you don't need the whole body.