Because we only live a short while, we don't take a long view and there's a soft cap on society's accumulated wisdom. (In a smaller scale it's like companies losing "institutional knowledge" when employees leave.) People would act differently if they knew they'd be around for 700y instead of 70.
> That's what we thought would happen [with the Internet], but look at what we actually did
You're not seriously suggesting humanity is better without the Internet…
I cannot speak for karaterobot, but that seems to be an unwarranted inference from the post you are replying to, which merely points out that the internet did not lead to the more cooperative and altruistic world that some idealists predicted.
You posit that humanity would step up to the challenges of a ten-fold increase in longevity, but I haven't seen what I would regard as persuasive evidence for that view. The fact that the internet has been a net benefit (a view I accept) is not that evidence, IMHO.
Internet idealism : Internet negatives¹ :: longevity idealism : longevity negatives²
¹flaming & porn ²scarcity & overpopulationThe problem is not resource scarcity, it's pollution. For example, Americans pollute far more than Indian, despite having a smaller population.
And those problems have to be solved first, we couldn't just say "well, let's multiply the population, then figure out what to do about it later".
I'm also very skeptical that, given an indefinitely extended lifespan, people would suddenly do all of those nice-sounding things you list. More likely they'd just do the exact same things they do now, for longer.
It sort of reminds me of the philosophy around the early internet: imagine if people could get access to all information and communicate with anyone, anywhere. Imagine how smart we'll become, how civilized! That's what we thought would happen, but look at what we actually did: yell at each other and watch porn. My guess is that if we lived forever, we wouldn't suddenly become interesting, enlightened people if we weren't already.