The Ash Twins Blog

Biological nepotism among humans presents a serious problem to the efficient and equitable function of modern societies. Nepotism predictably arises from the effects of kin selection, which, put simply, holds that genes that help their kin help themselves. Kin selection theory predicts that altruistic behaviors toward a target conspecific will be selected for inasmuch as they satisfy the inequality rB > C, where r represents the genetic relatedness of the target, B represents the fitness benefit to the target, and C represents the fitness cost to the actor. When this inequality is satisfied, the act results in a net fitness enhancement to the genetic endowment in question even if it imposes a fitness cost on the acting organism. Parental investment in offspring is an example of this theory’s dynamic, as well as sibling altruism, cousin altruism, and other forms of kin altruism. Kin selection is evident in human behaviors as, for example, when one babysits her younger sister or helps her pay for a new car.

More controversially, a CEO might hire her sister as vice president over a more qualified candidate. The reason that the second example is more trouble to our moral sense is that while the first example is harmless, the second example imposes negative externalities on the shafted applicant and–by potentially reducing revenues–onto the company as a whole. In both cases, the target’s rB is greater than the actor’s C, but a fourth term representing the sum of costs to other individuals of the act in question, ΣD, does not enter into the actor’s decision function. By reducing the incomes of the shafted applicant and of the other employees at the company, the CEO’s nepotistic hire also reduces their reproductive fitness–formally speaking, ΣD < 0.

Apart from the fitness-related externalities, it is also worth noting the utilitarian effects of nepotism. A serious question arises whether the kin-selection benefit accrued by the nepotistic actor should be included in a utilitarian calculus. Represent the kin-selection-related utility to the nepotistic actor as F, the utility to the beneficiary as G, and the sum of externalities as ΣH. Assuming that the actor’s kin-selective benefit is not included, that ΣH < 0, and that G < |ΣH|, then the aforementioned nepotistic hire imposes a net disutility on society and should be prevented by legal or other institutions. If F is included, and again assuming ΣH < 0, then the nepotistic act should be allowed when F + G > |ΣH|.

What “kin-selection-related utility” might mean is unclear, but it is clear that humans at least derive decision utility from nepotistic acts.