I watched a rather interesting and fairly long video recently that got me thinking about how we might decide on the practical benefits (or lack thereof) of religion.
Haidt finds himself in an argument with a bunch of the New Atheists (Dawkins, Harris, and others), and because I find both sides interesting I read more about the disagreements here. Needless to say I don't fully agree with anyone, but I do think looking at how they think and what they say about each other's positions is likely to be really thought provoking for anyone who is interested in thinking about the effects of religion divorced from any question of whether or not its supernatural claims are true. Everyone involved in this debate thinks God doesn't exist; they just can't decide what should be said about religion given that basic fact.
One of the things that stirs up a lot of controversy is the fact that in numerous studies religious people give more to charity than atheists. The difference is only 10%, but it is there. Note that this is after giving to religious organizations is stripped out, and that similar findings exist for blood donation and volunteering. Haidt uses this as a reason for us to consider the usefulness of religion and sanctity in general, and suggests that we might well be able to harness the power of belief to improve society. It is a worthy area of consideration because if we can make people's lives better than we ought to try to do that, I think, even if the methods might be distasteful to some.
The obvious counter argument is that religion, and sanctity in general, rely on falsehoods. At the very least they require guesses to be presented as facts and hopes to be presented as truths. We could argue that doing so is inherently wrong but that would hold up truth as something worth pursuing regardless of its effect on human well being, and I don't buy into that. I think truth is worth pursuing, but I think it is worth pursuing because it improves human well being, not because of any value inherent in it. Truth itself is not sacred, it is just a really good tool. Given that, I think that there is a huge downside to religion because I think truth itself is more valuable. However, I can't prove that; it is just my supposition.
A more appropriate counterargument, I think, is that the data showing that religious people are more giving is based on a highly biased sample. If you ask people in the US about their giving you may find that religious people give more, but you are asking that question in a country where serious president candidates say that an atheist cannot possibly be a good president. In that country bans on muslim immigration are being proposed, and muslims are increasingly being brazenly attacked on the street, certainly in some part due to inflammatory comments by political leaders. In that same nation atheists are even *less* trusted than muslims, but they suffer far less because they cannot be easily identified by their appearance.
In a nation so thoroughly dominated by a single religion you can't seriously expect that the charitable behaviours of religious and nonreligious people will be unaffected by that fact. Having your holidays be celebrated by most businesses, being able to wear your religious artifacts without question, and being able to get away with assuming that everyone is of your religion unless stated otherwise changes your place in the world. The question is, would religious people give more if they were the minority who was pushed out of top positions of power? If atheists ruled the US and the idea of a Christian president was laughable would those surveys still show religious people giving of themselves to others more than the majority?
I doubt we would see the same thing in that reversed scenario. I can't prove it, obviously, but I can suggest that people who are in a minority that is pushed to the margins spend greatly of themselves just trying to carve out their own space. They have less time / money / energy to spend, and they probably are less inclined to spend it on others. If you could do surveys about giving and generosity across many cultures and locations my suspicion is that you would find that the dominant groups were more generous to charities regardless of their religion or lack thereof.
Again, I can't prove that. But I don't think I need to, particularly. What I can say with confidence is that in a world where Abrahamic religions are extremely dominant you find that those in those religions donate slightly more to charities than those who do not believe.
That statement does not lead at all to saying that religious people would give more or less to charity in an unbiased sample. Unfortunately I don't see any good way to acquire such a sample, but if we ever do I will be terribly curious to see what it contains.