One thing it could mean is that if Alice came to believe her beliefs were mistaken, she would no longer value the happiness that they engendered;
First, this is true regardless of whether Alice's original beliefs were mistaken or not. It's quite possible for Alice to hold true beliefs and then wrongly decide they were not correct.
Second, the phrase says "is not" using unconditional present tense. It does not say "might not be in the future".
Re: first point, yes, that's true. "we don't value happiness that comes from having mistaken beliefs" does not imply "we always value happiness that comes from having true beliefs".
Re: point 2... I'm probably misunderstanding you.
Consider the following dialog:
A: "Drinking poison isn't valuable"
B: "But if I give Alice poison and she believes that it's medicine, then she will value drinking poison"
A: "Well, I suppose, but if she knew what it was, she wouldn't"
B: "But you didn't say 'Drinking poison m...
I was browsing my RSS feed, as one does, and came across a New York Times article, "A Village With the Numbers, Not the Image, of the Poorest Place", about the Satmar Hasidic Jews of Kiryas Joel (NY).
Their interest lies in their extraordinarily high birthrate & population growth, and their poverty - which are connected. From the article:
From Wikipedia:
Robin Hanson has argued that uploaded/emulated minds will establish a new Malthusian/Darwinian equilibrium in "IF UPLOADS COME FIRST: The crack of a future dawn" - an equilibrium in comparison to which our own economy will look like a delusive dreamtime of impossibly unfit and libertine behavior. The demographic transition will not last forever. But despite our own distaste for countless lives living at near-subsistence rather than our own extreme per-capita wealth (see the Repugnant Conclusion), those many lives will be happy ones (even amidst disaster).
So. Are the inhabitants of Kiryas Joel unhappy?