The reinforcing value of aggression

In a drive-by allusion, McCullough et al. acknowledge, but do not give due weight to, the intrinsically reinforcing aspects of aggression as a primary reward in exacting revenge. Several sorts of evidence indicate that some men enjoy aggression. Historic episodes, when subcultures enjoyed “recreational” fighting, include 15th century Venetian bridge fights, 19th century Irish “faction fights” (“Donnybrook” refers to a seasonal Irish fair featuring big fights), and end-of-season brawls among American loggers (Ingle Reference Ingle and Cross2004). Individuals in subcultures in which fighting is a norm, for example, some English soccer fans (Buford Reference Buford1992) and pub-goers (Graham & Wells Reference Graham and Wells2003), continue to provide subjective reports of pleasure in fighting; but even in samples not selected for fighting, a modicum of pleasure in aggression is reported (Ramírez et al. Reference Ramírez, Bonniot-Cabanac and Cabanac2005; cf. Nell Reference Nell2006).

Of course, beyond any intrinsic reward in activating the neural circuitry of aggression, its reinforcing value may be shaped by, for example, pride and self-esteem in fighting and winning and/or relief of tension and fear of harm. Developmentally, however, boys' pleasure in aggression appears as a major sex difference at least as early as age four (Benenson et al. Reference Benenson, Carder and Geib-Cole2008). Phylogenetically, aggression's reinforcing value has been demonstrated across many species; fish swim through rings, birds peck at keys, and mice and/or rats poke their noses in holes, press bars, and run across electrified grids just to attack a conspecific (e.g., May & Kennedy Reference May and Kennedy2009).

Anger versus rumination

If anger were its driving affect, revenge would be short-lived. Surveys suggest that ordinary episodes of anger persist for no more than about 30 minutes, usually less (Potegal Reference Potegal, Potegal, Stemmler and Spielberger2010). Unless revenge is taken in the moment, one must invoke anger transformed into rumination, which is a highly elaborated cognitive activity that includes detailed (sometimes fanciful) planning for the future. This accords with the advice of boxing coaches, military generals, and others who urge on their fighters the proverbial “Revenge is a dish best eaten cold.” At a pathological extreme, rumination on revenge that eventually results in a “catathymic crisis” can disrupt the would-be avenger's life for weeks, months, or even years.

Personality

In the context of anger, the frequency and intensity of revenge is likely closely associated with an individual's general level of hostility as indicated by, for example, standard measures of hostility or Big 5 (dis)-agreeableness, as the authors and others have shown. If so, how much variance in individual behavior is explained by cost-benefit analysis of particular situations versus general personality characteristics? Although individual hostility, enjoyment of aggression, risk-taking, and so forth could be treated as parameters in equations predicting revenge, if there are, for example, many individuals who never take revenge and/or many who always do, no matter how slight the offense, then revenge depends more on proximate personality than on ultimate causation as reflected in situational demand.

Witchcraft murders – Revenge against kin

Witchcraft trials in Europe and North America ended more than 250 years ago, but in parts of India, Sub-Saharan Africa, and elsewhere, thousands of people have been exiled or killed for being witches in the last three decades (Federici Reference Federici2010). A witchcraft believer who experiences misfortune or illness will suspect that the culprit is someone who harbors ill feelings toward him. In small communities, these may well be family members (kin or affines) because quarrels with them are the most likely. Remarkably, many children have been abandoned, injured, or killed by people including their parents (Adinkrah Reference Adinkrah2011; UNICEF Report 2010). Witchcraft accusations among kin, especially against children, contradicts biological fitness expectations and is more consistent with proximate psychological processes and beliefs.

Finally, the parenthetical comment that tantrums are among behaviors that children impose on parents “with impunity” requires more attention to detail. Across quite different groups of children, tantrums are composed of one set of behaviors reflecting anger (e.g., shouting, hitting) and a second set reflecting distress-sadness (e.g., crying, whining, and comfort seeking, Green et al. Reference Green, Whitney and Potegal2011; Potegal & Davidson Reference Potegal and Davidson2003; Potegal et al. Reference Potegal, Kosorok and Davidson2003; Reference Potegal, Carlson, Margulies, Gutkovitch and Wall2009). This differentiation has been replicated (Giesbrecht et al. Reference Giesbrecht, Miller and Muller2010). Anger and sadness/distress have different temporal profiles. Angry behaviors peak early in tantrums, then fade while sadness/distress behaviors remain relatively constant throughout. Thus, tantrums end with children's sadness/distress and comfort seeking. Functionally, the child's terminal sadness pulls for parent comfort-giving, that is, behavioral “forgiveness.” Thus, child sadness and corresponding parent comfort-giving help end the tantrum and repair social bonds that were just strained by the child's anger (Potegal Reference Potegal, Aureli and de Waal2000; Potegal & Davidson Reference Potegal and Davidson1997).