provides mathematical tools to analyze strategic interactions among rational
players (Ross, 2006). A classroom example of Game Theory is the so-called
Prisoner’s Dilemma, which analyzes the problem of cooperation between two
suspects who are interrogated separately. Since the police do not have evidence
against them, if both remained silent (cooperated) they would walk free
(optimal outcome). However, if one of them talks (defects) he gets only a
mild sentence while the one who remained silent would get the maximum
sentence (worst payoff). Since neither of them trusts their partner, both of
them talk to avoid the feared worst outcome and thus both receive a mild
sentence (sub-optimal outcome).^5
We will deal with different problems of cooperation in Chapters 8 and 9 in
more detail and consider more complex models of social interaction. How-
ever, the Prisoner’s Dilemma illustrates the basic problem and introduces
formal theories of religion as a basis of society. Imagine that both suspects
in the above scenario had previously given a strong, reliable signal of being
trustworthy cooperation partners. They would then know that the other party
trusts them and has no reason to fear that they would be betrayed. Conse-
quently, they would not be afraid of remaining silent and thus both would
walk free. As William Irons, Richard Sosis, and Joseph Bulbulia argued in a
series of articles, religious rituals are good candidates to solve such problems.
Irons developed his theory of religion based on hisfieldwork in northern
Iran as well as insights from game theory, especially R.H. Frank’s model of
emotions as reliable signals of commitment (Frank, 1988; Irons, 1996).^6
Giving a“real commitment,”Irons writes (2001, p. 292), means that one
would“behave in a particular way even if it is contrary to one’s self-interest.”
He suggests that the most reliable cultural signals of commitment are religions,
because the essence of religion is to behave in certain ways irrespective of one’s
self-interest (p. 293). Most importantly for our present discussion,“religions
are expressed in elaborate rituals that are costly in time and sometimes in
other ways”(p. 293). Further, rituals provide“extensive opportunities for
members of a community to monitor one another’s commitments to the
community and its moral code”(p. 293). Irons (p. 298) identifies four features
of religions that make them particularly suitable as commitment signals:
(1) they are learned over a long span of time while growing up; (2) they are
too complex to be imitated by outsiders; (3) the elaborateness of rituals
offers many opportunities to monitor others for sincerity; (4) learning and
practicing religion is costly in terms of invested time and otherwise. Irons
predicted that more costly religions are more effective in creating cooperation
(^5) This is the so-called Nash-equilibrium of the game, where neither player can improve their
situation unilaterally given their best estimate of their partner’s choice.
(^6) Frank’s original suggestions were about deterrence, a typical problem for game theorists
during the Cold War.
100 Cognitive Science and the New Testament