You don't exist before or after your life.[1] You only perceive anything during your lifespan. Since you can't perceive anything before or after, your life is infinite for you. Because when it ends, there would be no you to notice.
Of course, such immortality ain't about prolonged lifespan, but it doesn't make it less cool (just maybe slightly off-topic here?).
2 There is life after death:
Then you won't die as such, period.
So the only problems left with are the inconveniences of aging.
I'd like to hear some critique on this, though; the idea seems too bulletproof to me, I don't like it.
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[1] It may be impossible to correctly imagine the condition when there is no yourself, mainly because there would be no yourself in this situation (some kind of catch-22 here).
Assign variable X to be the number of years you have been alive, at least to your subjective experience.
An immortal will see X go to infinity. A mortal will see it go into the three digits if they're lucky. The fact that you can't perceive your own death doesn't mean you don't die.
You're right, it isn't about living longer. It's about our cognitive abilities, perhaps.
Using your metaphor… I think, variable X is going to infinity _in both cases_. It's just that we operate in an environment where the infinity equals to what is a finite number (two or three digit integer) in another system.
Another way to put this: One can't experience anything except one's life. Therefore, life is infinite to person's subjective experience (the only experience available).
EDIT: Okay, I think I see where we disagree. In my view, while what you perceive may not be the "reality" in some absolute sense, it is the only reality for you nevertheless. And your death doesn't exist there, much like dragons or wizards. In short, yes, the fact that you can't perceive your own death means that you don't die. You seem to have different point of view.
See, two possibilities exist.
1 There's no life after death:
You don't exist before or after your life.[1] You only perceive anything during your lifespan. Since you can't perceive anything before or after, your life is infinite for you. Because when it ends, there would be no you to notice.
Of course, such immortality ain't about prolonged lifespan, but it doesn't make it less cool (just maybe slightly off-topic here?).
2 There is life after death:
Then you won't die as such, period.
So the only problems left with are the inconveniences of aging.
I'd like to hear some critique on this, though; the idea seems too bulletproof to me, I don't like it.
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[1] It may be impossible to correctly imagine the condition when there is no yourself, mainly because there would be no yourself in this situation (some kind of catch-22 here).