The Suicide-Bomber Type

For this week’s reaction paper I will quickly define what a suicide bomber is, provide a summary of how similar people is acknowledged in the literature, and provide an experiment to test this hypothesis. This reaction paper thus summarizes the experiment I plan to run at the conclusion of this class.


A Consequence of Genotypic Polymorphism?

I define “suicide bomber” as follows: “a suicide bomber is the kind of person who purposefully loses his life in order to punish injustice.” More broadly, we might saw that “a suicide bomber is the type of person who will accept a fall in his position to a state below which he had at the beginning of a bargaining game in order to punish a free-rider.” This definition has three critical portions. First, it assumes that humanity can be divided into kinds or types that act in a semi-predictable manner. Second, it assumes that there exists humans who act altruistically instead of maximizing their own utility. Third, it accepts that this effect is translated into altruistic punishment.


Evidence for types is found everywhere. In a broad sense, men enjoy some types of violence more than women (Kotalak, Singer), and single men are more likely than attached men to “act in ways considered personally more dangerous but socially more meaningful” (Atran 1537). Additionally, in laboratory experiments have shown stable “strategies” of cooperation (Kuzban and Descioli).

Concerns over fairness can override an individual’s ability to think rationally. Or, rather, such concerns evoke a “rationality in design” that operates instead of a self-centered “rationality in action” (Orbell et al 14). Guth and Tietz (446), for example, write that “considerations of distributive justice seriously destroy the prospects of exploiting strategic power.” Atran described real-world suicide bombing as benefiting “the organization rather than the individual” as “rational choice [in suicide bombing] is the [group’s] prerogative, not the agent’s” (1537). Smith sums it up well when he writes In short, the other regarding, social aspect of decision making that drives the preference to appear fair should take precedence over any preference for individual gain” (1015). Further theoretical support for altruism is found Hammond and Axelrod (2006), who devised a mathematical model of ethnocentric altruism to because of “empirical evidence suggests that a predisposition to favor ingroups can be easily triggered by even arbitrary group distinctions” (2).

It also assumes that a concern for altruism (not being a first-order free-rider) implies a concern for punishment (not being a second-order free-rider). Yet here too, moralistic punishment has been observed in the lab (Kurzban, DeScioli, and O’Brien). Fehr’s work demonstrates that punishment continues even with no increase in an individual’s reputation (981), though it does increase with the seriousness of the infraction (980). In summary, ample evidence exists that there are fairness-concerned people who will forfeit gains in order to punish perceived cheaters.

To tie this all together, we need to demonstrate that “suicide bombers” are not merely altruistic punishers who are manipulated by organizations, but rather represent a distinct “type” “hardwired” (to use Smith‘s phrase) to punish with reserves in a bargaining situation where they perceived themselves to be suckered. This can be done with a variation of the ultimatum game. The subject plays an ultimatum game, where the subject is in the receiving position and a confederate (either a computer program or a living accomplish) is in the giver position. The confederate gives the subject a very unfair deal — say, a 9-to-1 split under circumstances where the confederate supposedly had an easier time getting to the experiment as the subject. A “rational man” would accept the nine-to-one split, while a typically fairness-oriented person would reject it. The suicide bomber type is expected to reject. However, the experiment would then give the subject the option of donating material he provided himself (either money, grade credits already earned in a class) etc), in order to punish from the cheater. If there is a “suicide bomber” type that exists without manipulation by organizations, a type should emerge in the experiment which makes such a sacrifice in order to punish the cheating accomplish. Further, if this suicide bomber type matches up with known suicide bombers, men should be over-represented in it generally, as should single men specifically.