Thanks to all three scholars for taking the time to read and critique the excerpt from my book The Evolution of God. A few thoughts in response:
Richard Joyce’s critique has convinced me that I should have been clearer about a few things. In particular: I’m not, as he asserts, “[morally] justifying tolerance by appeal to self-interest.” I’m trying to sell the idea of tolerance to, e.g., Americans on grounds that it would be in their self-interest. To the extent that I would morally justify tolerance, it would be on the utilitarian grounds that symmetrical tolerance will increase overall welfare. (And I might locate a slightly different kind of justification for tolerance in my view that tolerance can entail a literally truer view of the other—truer in a sense that space doesn’t permit me to spell out.) This clarification renders some of Joyce’s critique moot—at least as a critique of my views, though his analysis is valuable in clarifying various issues (and in convincing me that I haven’t been clear enough).
Joyce also complains that I’m telling a “just-so story” in suggesting that, as he accurately paraphrases me, it “was adaptive for our ancestors to be able to distinguish non-zero-sum from zero-sum games and respond accordingly.” He says that “someone who claims that there is such a mechanism needs to do much more than tell a plausible story about why such a skill would have been adaptive.” I beg to differ. I think I should be free to toss out a hypothesis on the basis of little evidence and then let people argue about it. That’s how a lot of progress in science has started. As it happens, in this case there is evidence that I could have invoked but didn’t–e.g., a large empirical literature on reciprocal altruism (i.e. on psychological mechanisms conducive to playing non-zero-sums) and on the derogation of rivals (i.e. on opinions we express and/or believe regarding people we perceive ourselves to be playing a zero-sum game with). There is also a large literature suggesting that our close relatives, chimpanzees, quite naturally distinguish between zero-sum (rivalrous) and non-zero-sum (coalitional) relationships and seem to have a suite of tactically appropriate behavioral responses. Though it’s not impossible that these behaviors result from conscious calculation, it seems much more likely that they are governed fundamentally by emotions; and it’s not very easy for me to imagine a plausible scenario in which these emotions, in so functioning, aren’t biological adaptations (i.e., aren’t “designed” by natural selection to facilitate the successful playing of non-zero-sum and zero-sum games).
Jonathan Sheehan is definitely right that the various players in a game may differ on the question of what constitutes a gain for each. My essay implicitly assumes that all players are free to define gain for themselves. Thus when I buy something the exchange is non-zero-sum because I would rather have the merchandise than the money and the merchant would rather have the money than the merchandise; our respective opinions about our own welfare are all that matters, and any objective “truth” about the value of the merchandise is irrelevant.
Sheehan concludes that “modern conflicts between ‘the West’ and ‘the Muslims’ have less to do with misfiring mental machinery, and more to do with the absence of any recognized authority for determining the kinds of games we are playing.” Well, I can certainly imagine a recognized authority with enough influence to settle these conflicts—but in most cases I can’t imagine such an authority showing up in the real world anytime soon. And, in the absence of such an authority, it seems to me that the mental machinery of the players is almost by definition central to solving the conflict (though whether I’m right that the machinery is misfiring is of course another question altogether).
Timur Kuran seems right to say that the terrorism-fomenting zero-sum perceptions I focus on are neither necessary nor sufficient to foment terrorism (though, obviously, I think they’re often very important). I find particularly valuable his emphasis on the social dynamics within Muslim societies, something he knows more about than I do. I’d be interested in his reaction to the speculation that sometimes the problem can be framed this way: The object of the game is to (a) get Muslim elites to view relations with the West as non-zero-sum (a task that in many cases has already been accomplished) and (b) get non-elites in that society to view their relations with these elites as non-zero-sum.
If that sounds too abstract, let me try to concretize it by reference to the fairly common phenomenon of populist nationalism. Populist nationalists gain traction by convincing lower-income people that they stand in a zero-sum relationship with some upper-income people who are gaining from non-zero-sum relations on the international front. The accusation, in other words, is that the upper class is doing business with foreigners at the expense of their lower-income compatriots. When attending international gatherings designed to soothe tensions between “the West” and the “Muslim world,” I’ve often noticed that the Muslim elites in attendance have abundantly cosmopolitan values, but I’ve wondered if they are resented by many non-elites in their societies, a resentment that then translates into anti-cosmopolitanism and anti-Westernism.
Thanks again to everyone.