and it happens to be exactly the same amount that Gateses are going to give their children
You say this as if it's a silly thing that no one could have good reason to believe. I've no idea whether it's actually true but it's not silly. Here, let me put it differently. "It just happens that the amount some outstandingly smart people with a known interest in world-optimization and effectively unlimited resources have decided to leave their children is the optimal amount."
I mean, sure, they may well have got it wrong. But they have obvious incentives to get it right, and should be at least as capable of doing so as anyone else.
And you know precisely that e.g. 10^7 USD is okay, but 10^8 USD is too much.
I doubt they would claim to know precisely. But they have to choose some amount, no? You can't leave your children a probability distribution over inheritances. (You could leave them a randomly chosen inheritance, but that's not the same.)
It seems like whatever the Gateses were allegedly planning, you could say "And you know precisely that doing X is okay, but doing similar-other-thing-Y is not" and that would have just the same rhetorical force.
couldn't you find a better solution?
I don't know. Could you? Have you? If so, why not argue "If the Gateses really had the goals they say, they would do X instead" rather than "If the Gateses really had the goals they say, they would do something else instead; I'm not saying what, but I bet it would be better than what they are doing."?
Again, I'm not claiming that what the Gateses are allegedly planning is anything like optimal; for that matter, I have no good evidence that they are actually planning what they're allegedly planning. But the objections you're raising seem really (and uncharacteristically) weak.
But I'm not sure I've grasped what your actual position is. Would you care to make it more explicit?
My actual position is that:
1) Gateses had some true reason for donating most of the money -- probably a combination of "want to do a lot of good", "want to become famous", etc. -- and they decided that these goals are more important for them than maximizing the inheritance of their children. I am not criticizing them for making that decision; I think it is a correct one, or at least in a good direction.
2) But the explanation that they want their children to "make their own mark on the world" is most likely a rationalization of...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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