Within an emotionally challenging situation many people already make that calculation. The result of that one, however, would actually change depending on the probability of future improvement.
Suicides do not happen because life is just unbearable (for most victims of suicidal thoughts this state prolongs for several months up to several years), but because after some time they are sure life will stay this unbearable.
Another thing is, death often seems less bad than it actually is.
Ask yourself: 50 years at Guantanamo Bay -- given that you do not suffer severe depression -- would you prefer death, if you would know that you could life another 20 years in liberty afterwards?
Then: Remember that in real life you most certainly do not know that integrated over the next 20 years there is really no chance that you could go free. Today -- political prisoner in China -- in 20 years?
The question of "worse than death" is usually dissolved by asking in what mode of operation the answer is given -- the "unbearable, unsolvable" mode, or the "unbearable" mode. Given the human failures, "unsolvable" is usually a mistake, especially when you can expect more than two decades of lifetime. The idealized questions of "how many years torture vs. death" are meaningless for a personal decision if you cannot predict the future with sufficient accuracy.
Of course, human psyche is weak -- everybody breaks -- at some point. That does not mean that the actualized preference is the correct one given the situation.
“If he thought like me, he’d have known that living in misery sucks marginally less than dying in it.”
-- Dr. House (fictional)
I cannot even imagine suffering 50 years at Guantanamo Bay. Is 20 potential years of freedom after 50 years in Guantanamo Bay worth enduring? Probably not, at least to me. Is there a point at which 50 years in Guantanamo Bay becomes worthwhile? Probably. I don't know exactly where that point is, but I know that it exists (e.g., 1000 yrs of satisfying life is worth it, but is 100?).
Given the human failures, "unsolvable" is usually a mistake, especially when you can expect more than two decades of lifetime.
I agree completely. This is ...
The claim has been made that, all things being equal, it is better to be alive than dead. I dissent.
It is much more complicated than this. If I knew somehow that I would spend the next fifty years of my life in Guantanamo bay, I would rather kill myself than suffer that fate. If a fortune teller showed me that I would be in a car crash and lose all sensory input, but would be kept blissfully comatose on cocaine and ecstasy, I would get my affairs in order and end my own life. And yet, if I knew that every day for the next 50 years I would be horribly tortured, but my experience would eliminate suffering from everywhere else in the entire world, I would accept the fate and do my best to steel my mind for the horror that would be my life.
I want to feel like my existence has purpose. I want to make the world a better place to live in for other people. I want to be happy and experience pleasure. These, not a primordial drive to keep myself alive, are my motivations. Killing myself would be the only rational chice if I knew that my life would be worse than my death.
I'm not trying to advocate suicide. I'm simply saying that the will to live is not a basic motivating factor for most human beings. So when the argument is made against life extending technology, rather than countering it with "all things being equal," try "existence being pleasurable..." But don't claim that existence of sentient beings is inherently good.