There's an objection to be made that you can't be sure how useful charity is, but it's not a very strong objection. Last I heard there was pretty good evidence converging around $1000 or so being enough to save a person's life.
I accept this argument as valid and have for some time. I doubt I could donate everything to charity, but ~50% seems like a good compromise between human weakness and inhuman mathematics. We'll see how far I follow through on this when I get an income.
You need to choose a very carefully targeted charity that takes into account knock-on effects like displacing local production, before you should accept any such claim. It is now being suggested that the majority of aid is actually counterproductive and destroys local industry in exchange for giving Westerners a warm fuzzy feeling. Hence Africa staying poor despite (because of?) hundreds of billions spent.
Frankly, if you're going to put in that much work into buying expected utilons at the cheapest available price, you shouldn't be considering any mainst...
I'd be really interested to hear what the Less Wrong community thinks of this. Don't spoil it by reading the comments first.
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