What are the implications of humans being able to live forever? And by "live forever," I don't necessarily mean endless biological life or endless existence in one's present body. Whether immortality takes the form of medically enhanced or technologically enhanced hominids, uploaded minds, etc., if one day individual human consciousnesses/minds are able to persist forever, what would be the philosophical considerations of such a possibility? Would individual existence be "better" simply by going on forever, or would it possibly lose value in important ways?
Would we still be ourselves in such a state, or would immortality so fundamentally change us that we would no longer be who we were as mortal beings? There is the argument that death gives form to human lives and that without the prospect of death, lives would be formless and lose most if not all of their meaning. There would be much less urgency to do anything in particular; one could always say "I'll get to that next decade" or "next century" or "next millennium." If death, to some extent, defines human lives, then removing that defining factor may change the meaning of lives. There is also the question of whether something is better just because it goes on forever. Temporal finiteness can give things greater value. Think of an endless symphony or sunset or conversation or hot bath. Is there anything that is good that would become that much better simply by going on forever?
On the other hand, if life is a good thing, isn't it better for that good thing to continue rather than for it to end? In response to this question, some who argue that immortality is not necessarily a good thing raise the analogy of eating ice cream. If eating ice cream is good, does that mean that an eternal ice cream binge is also a good thing, or even a better thing than ice cream binges that come to an end? But life is not analogous to eating ice cream. You don't get satiated with life like you do with ice cream, where if you eat too much, you get physically sick from it as well as psychologically sick of it. And isn't extending people's lives a good thing? Who wouldn't opt for another year or two or ten of life (assuming that those extra years did not involve inordinate suffering)? Wouldn't being able to live to 200 be better than living to no more than 35 or 75? So that no matter how much the human lifespan could be extended, the greater the lifespan, the better. By that logic, infinitely extending it would be better than having it reach its end, no matter at how advanced the age. Or would it? And even if humans can become immortal, that does not mean that death could not always be an option. If one gets so tired of being alive, after having lived for 10,000 years or so, one can always opt out of the deal, or maybe go into suspended animation for a millennium or two! And it seems that most of the reasons why people would not want to live forever have to do with the physical and mental decline associated with getting older and not with living per se.