Isn't there a real possibility that being removed from everything that allows us to perceive reality, psychological trauma could result?

..and with no ability to communicate with that brain in a jar, we'd have no idea what's going on inside of it. We could be putting it in hell and never know. It could be like the movie Waking Life, eternal dreaming without ever being able to wake up.

The title of the game/short novel comes to mind: "I Have No Mouth Yet I Must Scream."

> ..and with no ability to communicate with that brain in a jar, we'd have no idea what's going on inside of it.

We already know what happens to prisoners placed in solitary confinement; the effects on mental health are quite damaging over the long term. There have also been studies on partial sensory deprivation [0] and impairment of cognitive abilities and hallucinations began occurring within days. I can't find the appropriate references at the moment but total sensory deprivation, which is closest to the brain-in-a-jar scenario, is even worse than that IIRC.

[0] https://www.motherjones.com/politics/2012/10/donald-o-hebb-e...

> The title of the game/short novel comes to mind: "I Have No Mouth Yet I Must Scream."

Zelazny's "Go Starless in the Night" would be more appropriate and perhaps only slightly less horrifying.

You're still assuming it's not like sleep, and that you wouldn't be floating in a vat of chemicals/equipment that had an impact on your mental state. And you still shouldn't assume that death is preferable to solitary confinement or sensory deprivation.

> You're still assuming it's not like sleep, and that you wouldn't be floating in a vat of chemicals/equipment that had an impact on your mental state.

I'll point out that the current two-process model we have for sleep pushes the brain towards waking up after a while; Process C (circadian) on a periodic basis and process S after the brain's need for sleep is satisfied. That would need to be counteracted. I'll also point out that there's some evidence that even a few months of sedation will cause lasting cognitive damage, e.g. https://www.nejm.org/doi/full/10.1056/NEJMoa1301372, yet sedation for years, if not decades, would be necessary. The brain is not a machine; it does not shut down when asleep or sedated.

> And you still shouldn't assume that death is preferable to solitary confinement or sensory deprivation.

It is, of course, a personal decision and it might even be said to be the ultimate personal decision. However, not understanding the implications of one's choices, as best we know them, is unwise, don't you think?

Being a brain in a vat doesn't imply much though. I mean, you can't assume someone has lobbed your head of and crudely crammed it into a jar of formaldehyde. For all anyone knows, you're in The Matrix instead. So unless we constrain the problem, there's no more reason to assume it is torture than there is to assume it is euphoria.

As such, there are no implication to being a brain in a vat other than the fact that you don't experience the outside world. It says nothing about what you do experience. And it certainly does not imply permanent damage in the same way that death does.

If one is allowed to assume sci-fi, ... no, not even sci-fi, outright sci-fantasy levels of technology like the Matrix, the question becomes essentially meaningless. One might as well just say a new body will be instantaneously grown out of magical quantum nanobots created by the Singularity the second the brain in the vat scenario occurs and avoid any of the hard questions raised about becoming a brain in a vat in the first place.

Since none of that is likely to happen here in the real world, ever, it makes far more sense to take a hard science approach based on what is known to be at least theoretically possible today.

Brains-in-vats have only ever been science fiction. Regardless, there's nothing about anything I've said that is known to violate any laws of physics, so your objection to 'magical' extrapolations is irrelevant. I say "The Matrix", but obviously you can substitute any number less fanciful mechanisms into the process -- psychotropic drugs & electromagnetic stimulation are not fiction.

Psychological trauma is still better than death. Besides you could ask the same question in reverse:

Isn't there a real possibility that being subjected to circumstances that allow us to perceive reality, psychological trauma could result?

Or maybe every computer on Earth is right now a mind in a perpetual state of torture. I don't see how a brain in a vat shouldn't be any less objectionable, especially if we're relying on blind conjecture.

> Psychological trauma is still better than death.

Is it? If the Mona Lisa were set on fire, there would be effectively zero hope of reconstructing it from the ashes. Can a sane original mind be reconstructed from insanity caused by severe trauma or extended sensory deprivation or dementia? There too, the pattern has been destroyed; there's effectively zero hope of restoration.

Who are you to decide what I choose to do with my body? Who are you to choose what are my values?

You are not. I am.

And I choose to live.

> And I choose to live.

Have you ever seen firsthand a person in the final stages of Alzheimer's disease? If life is so precious to you that you are willing to exist for eternity in such a state, far be it from me to tell you otherwise.

May you enjoy the outcome of your choices.

Choices can change. This would require some changes in laws on euthanasia obviously, nothing insurmountable.

Presuming you would actually live in such a state even - perfecting this technology will require other ground breaking research, some of which might be able to handle Alzheimer's.

> Choices can change. This would require some changes in laws on euthanasia obviously, nothing insurmountable.

Sure but questions arise:

"How much mental trauma/cognitive damage can a normal human mind sustain before it is no longer capable of comprehending its choices (or even the concept of "choice") at all?"

"Will the brain-in-a-vat scenario exceed that limit?"

> ...some of which might be able to handle Alzheimer's

As I alluded to before, is it possible to unscramble an egg?

You can assume being a brain in a vat would be torture, but I see no reason to assume it wouldn't be euphoria. Either way, life is better than death. Living in any state gives technology more to work with than turning to dust would.

How would a technological brain-in-a-vat hell of unending torture be "more interesting" and "useful" than death?

How can 0.0001 be greater than 0? Death is very uninteresting and useless, and most importantly, offers almost no possibility of being reversed.

There seems to be at least one positive to death: the end of the struggle. If you don't exist you don't need to worry, to suffer, to care. There's a certain type of comfort in knowing that at the end of it all, it's really not that important. Immortality seems to me as too many paths to a hellish existence, especially since we aren't adapted to such an existence, psychologically or physically.

This veers into the realm of philosophy but potentially almost everything we enjoy about life may be because of our mortality, even the feeling of happiness itself may be derived from knowing that tomorrow we may be dead. An immortal existence seems so different from the human experience that I can't say that it has a high chance of being a positive thing.

You can consider that a positive, but it is also an inevitability. Nobody is talking about immortality here. But you also wouldn't be saying the end of all life would be positive (which you could, for exactly the same reasons) and that still wouldn't mean you shouldn't delay it for as long as possible.

>almost everything we enjoy about life may be because of our mortality

You don't know that you're mortal until you die. It makes no difference here, because even if this were true, you are already assuming you are mortal regardless of the facts, and you will continue to do so. Being immortal doesn't imply you've also reached some state of deep enlightenment about it.

Besides, you can invert this just as well: everything we enjoy about life may be dependent upon the belief that we're not going to die soon.