[ETH_start]

In principle, a greater number of future lives matter more than a lesser number of present lives. The principle itself seems sound to me.

The problem is you can't actually be certain those future lives will come to exist. One assuming they will, and being so confident in their assumption that they deprioritize the lives of the currently living based on it, is hubris, but only because it over-estimates one's powers of prognostication.

[maxbond]

If we agree the principle can't be applied - why would we consider it sound? That's like saying the principle behind 1 + 1 = 3 is sound, with the small caveat that you get the wrong answers. If something looks good on paper and turns sour when we try to use it, that's the indication that we've miscalculated.

Another perspective to consider; the best way to help people in the future is to help people today. Solving the challenges of our time is an investment that will compound into the distant future. Speculating on what life could be like in a hundred or a thousand years, and tailoring your efforts to that imagined future, is much like creating a product without a customer in mind. If you end up with something useful, it's almost certainly on accident and not because your speculation was accurate.

[ETH_start]

A principle can be sound while not being applicable. Principles and applications are two separate things and there's no reason to conflate them.

>>That's like saying the principle behind 1 + 1 = 3

That's not sound in principle..

>>Another perspective to consider; the best way to help people in the future is to help people today.

That is an entirely valid, and I would argue probably correct, perspective yet it doesn't invalidate the principle that a greater number of future lives matter more than a fewer number of current lives. It may be that the best course of action for both future lives and current lives is to pursue the best interest of the currently living.