Dec 22 JDN 2458840

Christmas is coming soon, and it is a season of giving: Not only gifts to those we love, but also to charities that help people around the world. It’s a theme of some of our most classic Christmas stories, like A Christmas Carol. (I do have to admit: Scrooge really isn’t wrong for not wanting to give to some random charity without any chance to evaluate it. But I also get the impression he wasn’t giving a lot to evaluated charities either.) And people do really give more around this time of year: Charitable donation rates peak in November and December (though that may also have something to do with tax deductions).

Where should we give? This is not an easy question, but it’s one that we now have tools to answer: There are various independent charity evaluation agencies, like GiveWell and Charity Navigator, which can at least provide some idea of which charities are most cost-effective.

How much should we give? This question is a good deal harder.

Perhaps a perfect being would determine their own precise marginal utility of wealth, and the marginal utility of spending on every possible charity, and give of your wealth to the best possible charity up until those two marginal utilities are equal. Since $1 to UNICEF or the Against Malaria Foundation saves about 0.02 QALY, and (unless you’re a billionaire) you don’t have enough money to meaningfully affect the budget of UNICEF, you’d probably need to give until you are yourself at the UN poverty level of $1.90 per day.

I don’t know of anyone who does this. Even Peter Singer, who writes books that essentially tell us to do this, doesn’t do this. I’m not sure it’s humanly possible to do this. Indeed, I’m not even so sure that a perfect being would do it, since it would require destroying their own life and their own future potential.

How about we all give 10%? In other words, how about we tithe? Yes, it sounds arbitrary—because it is. It could just as well have been 8% or 11%. Perhaps one-tenth feels natural to a base-10 culture made of 10-fingered beings, and if we used a base-12 numeral system we’d think in terms of giving one-twelfth instead. But 10% feels reasonable to a lot of people, it has a lot of cultural support behind it already, and it has become a Schelling point for coordination on this otherwise intractable problem. We need to draw the line somewhere, and it might as well be there.

As Slate Star Codex put it:

It’s ten percent because that’s the standard decreed by Giving What We Can and the effective altruist community. Why should we believe their standard? I think we should believe it because if we reject it in favor of “No, you are a bad person unless you give all of it,” then everyone will just sit around feeling very guilty and doing nothing. But if we very clearly say “You have discharged your moral duty if you give ten percent or more,” then many people will give ten percent or more. The most important thing is having a Schelling point, and ten percent is nice, round, divinely ordained, and – crucially – the Schelling point upon which we have already settled. It is an active Schelling point. If you give ten percent, you can have your name on a nice list and get access to a secret forum on the Giving What We Can site which is actually pretty boring.

It’s ten percent because definitions were made for Man, not Man for definitions, and if we define “good person” in a way such that everyone is sitting around miserable because they can’t reach an unobtainable standard, we are stupid definition-makers. If we are smart definition-makers, we will define it in whichever way which makes it the most effective tool to convince people to give at least that much.

I think it would be also reasonable to adjust this proportion according to your household income. If you are extremely poor, give a token amount: Perhaps 1% or 2%. (As it stands, most poor people already give more than this, and most rich people give less.) If you are somewhat below the median household income, give a bit less: Perhaps 6% or 8%. (I currently give 8%; I plan to increase to 10% once I get a higher-paying job after graduation.) If you are somewhat above, give a bit more: Perhaps 12% or 15%. If you are spectacularly rich, maybe you should give as much as 25%.

Is 10% enough? Well, actually, if everyone gave, even 1% would probably be enough. The total GDP of the First World is about $40 trillion; 1% of that is $400 billion per year, which is more than enough to end world hunger. But since we know that not everyone will give, we need to adjust our standard upward so that those who do give will give enough. (There’s actually an optimization problem here which is basically equivalent to finding a monopoly’s profit-maximizing price.) And just ending world hunger probably isn’t enough; there is plenty of disease to cure, education to improve, research to do, and ecology to protect. If say a third of First World people give 10%, that would be about $1.3 trillion, which would be enough money to at least make a huge difference in all those areas.

You can decide for yourself where you think you should draw the line. But 10% is a pretty good benchmark, and above all—please, give something. If you give anything, you are probably already above average. A large proportion of people give nothing at all. (Only 24% of US tax returns include a charitable deduction—though, to be fair, a lot of us donate but don’t itemize deductions. Even once you account for that, only about 60% of US households give to charity in any given year.)