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Beyond Revenge: The Evolution of the Forgiveness Instinct

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Compared to the vast number of books on the science of happiness published in the last few years, there is almost nothing on forgiveness. When you consider that every human being will be wronged, betrayed, aggressed against, and hurt by another person as well as witness wars, genocides, and atrocities at home and abroad, it's about time that an expert culled together all there is know about what leads people to forgive as opposed to executing revenge.

McCullough's book is incredibly refreshing because he provides a new lens to understanding forgiveness and in turn, how to successfully maintain harmonious relationships (whether it is between people or nations). Instead of mindlessly touting the beauty of forgiveness and the evils of vengefulness, McCullough captures the complexity of these topics. Essentially, we are hard-wired to be both forgiving and vengeful and we need to understand how these strategies developed over the course of evolution to be able to wield them effectively.

I am always impressed when a scientist can describe complex ideas in an extremely interesting and simple manner. McCullough walks the reader through fascinating research studies and provides an excellent presentation of how the brain evolved to add both a craving for revenge and desire to forgive to our toolbox for dealing with other people. Yet, the best chapters are when McCullough moves from this research to the real-world. References to the ongoing war in Iraq, the "code of the street" in volatile inner cities, and the distinguishing features of diverse cultures bring his theories and research to life. He provides compelling logic for how to create the best conditions for people to be more forgiving and for nations to resolve their differences with the best possible outcomes in the aftermath of death and destruction.

Too many books are written by journalists and freelance writers reading and summarizing the work of scientists. Michael McCullough is one of the most prolific and influential thinkers on forgiveness and morality. There are only a handful of people who are qualified to write this book. Based on his own original research, new interpretations of old findings, and ability to dispel long-standing myths (for example, that revenge is rare and a sign of pathology), it is obvious that McCullough is one of them.

Anyone interested in evolution and understanding human nature, should read this.
Anyone interested in justice, morality, and the reduction of conflict, violence, and war, should read this.
Anyone interested in enhancing their own lives and learning about fundamental strengths that exist in some capacity in all of us, should read this.
Anyone interested in being intellectually stimulated, should read this.

On the back of the book, Richard Wrangham says that "every Secretary of State should read it." I couldn't agree more. This book is relevant to everyone because we all have far too much first-hand experience with the suffering caused by other people. Don't get me wrong, this book is not overly political and it is not cynical. You will walk away with a sense of optimism about how forgiveness can be cultivated in a complex and demanding world.

Author of Curious?: Discover the Missing Ingredient to a Fulfilling Life

Searching for books on forgiveness in amazon gives you 127,000 results. From the ones I've seen, the message is almost always the same: forgive those who hurt you because god wants you to, and because it will make you happier and healthier. I've always found that message to be too simplistic. If forgiveness is so great, why is the temptation for revenge so deeply etched in our brains? Aren't there cases where a lack of forgiveness can be healthy or even moral?

What I like most about this new book by McCullough is that he takes these questions seriously. He doesn't take a tendency for revenge to be sick, immature, or theologically misguided. Instead, in a very balanced way, he considers both revenge and forgiveness to be part of human nature, and even reviews evidence in species ranging from guppies to chimpanzees to people showing that forgiveness can be most beneficial when it is coupled with a tendency to punish people who want try to take advantage of you. This very readable book does not preach, though it does express hope for a more forgiving world, offering suggestions based on solid science about how to bring this about.

It takes a subtle mind to ask the seemingly straightforward question, "Why forgive?" In the same way that sexual reproduction was taken for granted before it was recognized as a phenomenon in need of an explanation, the first step in understanding forgiveness was recognizing that there are plenty of good, functional reasons to take revenge. Identifying this as an important and interesting research area would have been itself a powerful contribution. McCullough goes beyond this, however, and provides elegant answers to the question which others had failed even to ask.

The importance of "Beyond Revenge" extends past its contribution to the specific question it asks and answers. In many ways, Mike McCullough represents the best of a newly emerging kind of social scientist: a major player and intellectual force steeped in the data-rich tradition of social psychology, bringing to bear the powerful lens of an evolutionary/functional analysis. This book does more than give a lively (and quite possibly correct) explanation for the function of forgiveness. It provides a blueprint for carefully applying principles of biology and evolution to understand the enormous amount of data generated by a century of social science research. In bringing together his deep knowledge of a research area, and combining it with a penetrating evolutionary analysis, McCullough has potentially inspired not just readers, but possibly the next generation of social scientist to make use, in serious and rigorous fashion, of the conceptual tools furnished by evolutionary approaches to behavior. This book ought to be read by anyone interested in revenge and forgiveness... and by anyone who wants to see the direction of the social sciences, with Mike McCullough in the vanguard.

The "Nature" versus "Nurture" debate is a perennial topic. In Beyond Revenge, McCullough suggests that both revenge and forgiveness are hard-wired into us as social primates. In doing so, he manages to distinguish his claims that such human behaviors are natural from fatalistic conclusions, because "natural" does not connotate a justification for vengeful actions, nor does it suggest that natural behaviors are unavoidable.

It's a compelling argument that McCullough makes, and a difficult task to balance a presentation of the science with readability for reaching a broad audience. That is, his descriptions of behavioral studies in humans, primates, and game theory modeling seem to lose their potency in the course of the storytelling. Large parts of it come across as just what McCullough seeks to avoid: adaptationalist "just-so" stories. His argument is well-written and persuasive nonetheless.

For instance, his description of Robert Axelrod's work on game theory modeling and cooperation is extremely insightful and resounding proof that natural selection actually leads to a *nicer* world in the long run. Primate studies, as he describes them, also suggest that the standard response - and healthy - mechanism of closure to an act of aggression is forgiveness and reconciliation. Human psychology studies back this up, and identify the components of apologies that elicit forgiveness the best.

And in the next-to-last chapter, he debunks the notion that religion is the shortcut to forgiveness and compassion. True, as McCullough notes, religious individuals often forgive more readily - *if* the offender is part of the same social network, and particularly if the offender is part of the same religion. Moveover, devoutly religious individuals are more likely to exhibit more intolerant and vengeful attitudes towards offenders who are outsiders, on the margins of society, etc.

The last interesting item that struck me, reading Beyond Revenge, was something that I don't think McCullough stressed enough considering his argument that revenge and forgiveness are natural behaviors. That is, the differences between revenge and retaliation - revenge requires planning and forethought as provided by the pre-frontal cortex (something that our primate relatives lack compared to us). A similar difference exists for forgiveness and reconciliation, which McCullough mentions but does not elaborate on. These concept pairs are related though, and despite the role of our mighty pre-frontal cortex, are all part of our primitive emotional drives.

So I liked the book. In a world of suicide bombers and pre-emptive invasions, it is an important book. We can influence the cycle of retaliation that exists in a harsh world by considering the psychological factors that activate "the forgiveness instinct."

There is a surface structure to forgiveness and a deep structure. The surface structure approach emphasizes the importance of practicing forgiveness and suggests strategies for its cultivation. The deep structure approach attempts a comprehensive understanding of the roots of forgiveness and the personal and cultural conditions that either enable or obstruct it. This profound book is of the latter variety. Geared toward the intellectually curious, McCullough analyzes and elaborates on three basic scientifically revealed truths: (1) The desire for revenge is built in to the human species; (2) The capacity for forgiveness is similarly hard-wired; and (3) Modifying social environments will facilitate less revenge and more forgiveness. McCullough wants us to understand where the capacity for forgiveness and the propensity for revenge come from and what the implications are for improving our lot in life. As you are reading, McCullough's insights will cause you to pause, reflect, and say to yourself "I've never thought of that before." We owe him significant gratitude for causing us to think more deeply about the nature of forgiveness and its vicissitudes.

I love this book. I'm just glad I don't have to take a test on it, given that it is chock full of relevant data and resources.As a professor, therapist, and author, I ride on the backs of competent, productive people like McCullough, to whom I am really grateful.

If I got it right, his optimistic thesis is that both revenge and forgiveness serve evolutionary ends. Forgiveness, he suggests, is granted to those who are part of one's in-group, the ones on whom you depend for survival. Revenge goes to the out-group, one's competitors. Maybe I'm reading my own stuff into it, but it seems to me his point is that our in-groups are getting larger, therefore enlarging the size of the group to which we are willing to grant forgiveness. Even as I write this, it occurs to me that the terrible wars in Iraq and Afghanistan may ultimately serve the purpose of enlarging our sense of closeness to people who once seemed outside our purview.

I liked the fact that he emphasized the seeking of forgiveness as well as the granting of it. As a professor, and even as a therapist, I really glommed on to what I understood to be the three steps to evoking forgiveness from one you have hurt. (1) Clearly, sincerely, and genuinely accepting blame. (As opposed to that wimpy, basically meaningless, but too common "If what I did has hurt anyone, I am sorry.") (2) Demonstrating a deeply felt, self-abasing apology, and perhaps even a promise of some kind of restitution. (Evoking, by the way, another evolutionary human characteristic, empathic reaction,)and (3) Providing convincing assurance that the offense will not happen again. (Assuring the "forgivers" safety.)

In response to one reviewer, however, I'd like to point out that not all forgiveness authors require forgiveness. Forgiveness is a choice, and one can choose not to grant it. It's self-serving on my part (perhaps also rooted in evolutionary process ... ) but I'm attaching a link to my own books.

Revenge and forgiveness are two behaviors that get lots of attention in modern society. On one end, popular movies and books (at least from Western cultures) glorify vengeful behavior. Protagonists succeed by using violence that is morally justifiable. On the other hand, there is much public interest in forgiving others and living the good life. This is a common topic in the realm of talk shows and self-help books. The fact that humans are fundamentally social animals makes these behaviors critical to understand for the sake of our survival. Yet, the cultural dialogue on these behaviors is limited and unable to go beyond this simple dichotomy of prescribing revenge to correct for injustices and forgiveness to nurture your health and soul. McCullough's book is refreshing because it elevates our understanding of these two behaviors and illustrates a way to bring about a more forgiving and healthy world, all while it entertains and captivates.

"Beyond Revenge" effortlessly weaves together examples from recent news and history with evidence from such fields as psychology, anthropology, criminal justice, neuroscience, and evolutionary biology to describe the unique social functions that revenge and forgiveness serve for humans but also for other social species. There are not only references to many societal challenges, like violence in the schools and inner cities to the warring factions in Iraq, but there are also many keen observations sprinkled throughout based on the thoughts of prominent writers and philosophers. This masterful work will make you think seriously about -- maybe even rethink -- how friends, family members, communities, and even nations can build peace and lasting well-being. With each chapter, McCullough takes the reader on a journey through both ordinary and extraordinary cases of vengeance and forgiveness with an eye toward bringing scientific insight to bear on the greater social forces at play. By the end, the reader is surprised to learn that, no matter how great differences and conflicts get between people, humans have an amazing capacity that has not been fully utilized. True to the title, the challenge set forth in this book is for society to harness the will and creativity to bring social conditions in line with our ability to be constructive and caring beings. McCullough has provided a compelling plan for putting this capacity into action.

Beyond Revenge gives helpful insight into humanity's most troublesome problem (revenge) and the nearly universal desire/need to forgive. By understanding the nature and source of our emotions, we recognize and address them more effectively. In this way, society may soften the desire for revenge, while fostering the conditions of forgiveness.

What prompted this review however, was the bizzare assertion that McCullough disparages religion and, in particular, Christianity. Having read those reviews, it felt as if I'd read some redacted version. I can only imagine that some people will take offense to anything that suggests that animals, including humans, have biases rooted within their brain. McCullough never suggests these biases represent destiny, simply that theyare one prod among many. It would be a great pity if religious Christians turned their back on this book, because nothing prevents McCullough's ideas from co-existing merrily with religion.

For those familiar with Aristotle's Golden Mean, the Buddhist Middle Way, or Bertalanffy's principle of dynamic equilibrium, the emergence of a new synthesis of positive and negative psychology will be no surprise. A more balanced approach to scientific analysis of the `good' and the `bad' in human nature is now emerging, and few researchers approach this balanced approach to analysis better than does Michael McCullough in his book, Beyond Revenge: The Evolution of the Forgiveness Instinct.

McCullough begins by placing side-by-side two classics texts on ape society: Frans de Waal's book, Good Natured, and Wrangham and Peterson's book, Demonic Males. An obvious and yet striking contrast emerges. Ape society includes highly moral behaviors: setting and enforcing rules that benefit the group, sharing with the needy, sympathizing with those that suffer, offering consolation to the vanquished, and returning favors to the generous. Nevertheless, coalitional bonds between males within the ape community often serve to fuel an attack-on-sight ethic toward individuals from other communities, and McCullough reminds us that this tendency to maintain one set of rules for kith and kin, and a very different set of rules for outsiders is similarly prominent in human societies.

More generally, McCullough argues that revenge is not a disease and forgiveness the cure: both revenge and forgiveness are aspects of human nature, instinctual patterns of behavior that are context sensitive, and if we want to make the world a less vengeful, more forgiving place we need to make social environments less abundant in the factors that evoke the desire for revenge and more abundant in the factors that evoke the forgiveness instinct.

Broadly speaking, when it comes to thinking about behavioral change, there is an important difference between Michael McCullough and those who emphasize self-determination [1]. Specifically, rather than talk about forgiveness as a strength of character that mediates the relationship between the environment and behavioral outcomes [2], McCullough highlights the key role the environment plays in shaping (or evoking) evolutionarily stable behavioral strategies.

"Human nature is what it is...it's pretty well locked in. But there's a hopeful paradox waiting in the wings: our fixed, evolutionarily shaped, genetically superintended human nature is flexible, multifarious, and exquisitely sensitive to context...Helping humans adapt to the contingencies that present themselves is one of the things that human nature is for. Change those contingencies in one way, and more revenge results. Change them in another way, and more forgiveness results. So if you mater the contingencies governing the human desire for revenge and the human propensity to forgive, then you can go back to your home, your school, your workplace, or your community and make it a less vengeful, more forgiving place." (xix)

Aside from his strong emphasis of evolved instincts, McCullough's general approach to behavioral change would be more acceptable to advocates of functional contextualism than is the approach to behavior change emphasized in self-determination theory [3]. Functional contextualists search for variables that predict a particular event and would, if manipulated, affect the probability or prevalence of the event. Analyses that allow only for the prediction of behavior, or analyses that rely on non-manipulable variables, are considered inadequate or incomplete. Consistent with McCullough's view, any scientist seeking to influence levels of forgiveness would not only need to search for variables that predict forgiveness, but also isolate variables that when manipulated would influence the probability or prevalence of forgiveness (as operationally defined by the analyst).

And it will probably be no surprise to the average person on the street that revenge and forgiveness are elicited by certain social conditions. For example, few of the boys I attended school with would likely be surprised to learn that reward/pleasure centers in the brain are activated in men (but not women) who observe a defector being punished, that is, someone who treated them unfairly in an economic game [4]. Under certain conditions, boys and men may take pleasure in punishing a transgressor, but McCullough's review of the literature also points to three important factors that inhibit revenge and promote forgiveness instead. First, people are more likely to forgive those whom they feel close, care about; or those who are suffering and who cannot help themselves. Second, people forgive to the extent that they perceive their relationship with the transgressor to be a valuable one. Third, people forgive to the extent that they perceive the transgressor as unwilling or unable to harm them in the future. McCullough believes that these three variables - careworthiness, expected value, and perceived safety - are open to manipulation in projects of social redesign. The key challenge in promoting forgiveness involves creating the social conditions that signal and activate careworthiness, value, and safety amongst `strangers' -- because `friends' generally signal and activate successfully in this respect -- and one of the key influences involved in the process of transforming `strangers' into `friends' is the extent to which society creates opportunities for people to work together toward common goals (cf. Chapter 9).

As noted by McCullough in Chapter 6, the conciliatory tendency is strong in human infants and near universally observed by anthropologists across cultures. Therefore, if we can somehow extend the hand of friendship across cultures and expand global awareness of the forces that activate revenge and forgiveness, then, perhaps, Homo sapiens ("man the wise") will learn to shape Homo ignoscens ("man the forgiver") in powerful new ways (cf. Chapter 11). Religion may be part of the solution. However:

"...if you want religious groups around the world to be forces for forgiveness, you need to create the conditions that will cause then to perceive that forgiveness is in their best interests." (p. 223).

Returning to the evolutionary pillar of McCullough's worldview, the relationship between forgiveness and revenge in the context of in-group (friends/working partners) and out-group (strangers/competing groups) classifications becomes clearer. McCullough sees forgiveness and revenge as two sides of the same coin, a coupled pair of instincts that have evolved as an evolutionarily stable strategy (ESS), a natural byproduct of an evolutionary winnowing process. He draws upon game theory simulations to argue that tit-for-tat strategies of cooperation and retaliation are critical for ensuring inclusive fitness in a group -- cooperate if your partner cooperates, retaliate if your partner defects, and forgive your partner and return to cooperation if they repent. There are different versions of same strategy (e.g., generous tit-for-tat, which unconditionally forgives one third of the time after a defection; and contrite tit-for-tat, which forgives righteous anger), but all game theory simulations point to the same conclusion: only organisms that can forgive those they work with will survive the evolutionary winnowing process.

However, the results of any game theory simulation depend on the assumptions used in the mathematical specification of game contingencies (cf. Chapter 5). For example, if we add the assumption that we are `stuck with' those around us (family, neighbors, work colleagues) and thus suffer more as a result of retaliation (i.e., if we model functional proximity contingencies), game theory simulations find evidence for success of the strategy known as `very generous tit-for-tat'. Very generous tit-for-tat will forgive `buddies' unconditionally about two-thirds of the time. Unfortunately, part of this strategy also includes taking advantage of strangers, or cooperating with them only if one has few friends. But we can also add assumptions about the spread of gossip and the consequences of having a `good' reputation (he cooperates with group members) or a `bad' reputation (he takes advantage of the group). In this context, another set of optimal play strategies emerge. Specifically, optimal game play involves the application of multiple play strategies and the ability to keep track of who's who in the game. First, those with a good reputation who interact with someone who defects assign that person a bad reputation for the next round of play. Second, if you have a good reputation and you interact with someone with a bad reputation, you should defect. Third, if you have a bad reputation and you interact with someone with a good reputation, you should cooperate, even if they defect, and thus try to restore your good name. Fourth, those with a good reputation benefit from working with others with a good reputation.

Evolutionary thinking and game theory simulations are certainly interesting in the sense that they possess explanatory appeal, and from the perspective of someone whose objective it is to use these theories to promote forgiveness they also appear useful: forgiveness is a context sensitive byproduct of strong reciprocity and all we need is a means to optimize the conditions of game play such that more and more positive, cooperative, forgiving patterns of strong reciprocity manifest in the future. However, to further develop McCullough's thinking, we need to consider some critical comments.

First, in the absence of an explicit theoretical bridge linking phylogenesis and ontogenesis, and another bridge linking theory to effective action, many developmental psychologists will recognize evolutionary psychology as providing little more than a limited set of overgeneralizations that neither fit very well with the reality of behavioral dynamics [5], or help a group of key stakeholders to resolve their complex real world problems [6]. Game theory simulations suffer a related problem - they are rationally constrained, highly over-generalized representations of small group dynamics that do not necessary fit with the reality of everyday group behavior. For example, researchers have identified individual differences in patterns of game play that cannot be easily accounted for by the unifying frameworks of evolutionary theory and game theory. Although the majority of participants can be classified as reciprocators, a significant percentage are either consistent free-riders or consistently generous [7, 8]. Consistent free-riders and the consistently generous are, presumably, not going to be `successful' in the long run, as the free-rider will become an outcast and the consistently generous will be taken advantage of. Some ontogenetic analysis (e.g., analysis of learning history; analysis of action development in context) needs to be included if we are to understand these curious patterns of game play. To what extent and in what way are these behavioral profiles leading to `success' or `failure'. Mc Cullough does not talk about individual differences in this regard.

Perhaps the consistently generous achieve `success' in some contexts (e.g., as spiritual leaders in a monastic setting), but `fail' in other contexts (e.g., the Tibetan monk who is politically tramped by Machiavellian Chinese authorities). Thus, in terms of teaching people to become more successful and in terms of helping global societies to function more effectively, perhaps what psychologists need to do is to design creative new ways to help people cultivate requisite levels of forgiveness and revenge, such that tit-for-tat inclusive group fitness remains stable and curbs the behavior of those to take advantage of the system while helping those who are being taken advantage of. The wise psychologist who acts as game play moderator in these situations cannot be all-forgiving, much like they cannot be selfish. And this begs the question: what is the relationship between wisdom and forgiveness as manifest in everyday actions? What is the relationship between Homo sapiens and Homo ignoscens? Positive psychology clearly opens up a whole new world of game play for analysis. Michael McCullough is pointing us in an interesting direction.

Furthermore, although game theory simulations assume that behavior is under the control of rational contingencies, researchers have found that information that is independent of the formal structure of an experimental game can impact on players' behavior. For example, one study reported that oblique eye contact or light taps on a shoulder or arm significantly increasing contributions by males in an economic game [9]. In other words, there may well need to be an expansion of the definition of what is `rational' or `logical' in the psychological response of people playing real world games, and some of the logic of real world game play may well be beyond our current simulation capacities [10].

Likewise, game play strategies are a function not only of game play contingencies, but also of how games are cognitively framed. For example, people are more generous when a game is framed as a community social event than when it is framed as an economic investment [11]. Thus, unlike mathematicians, most people do not see these games as abstract structures that can be logically analyzed; some cognitive framing is required to determine the context that agents find themselves in. But none of this necessary detracts too much from McCullough's thesis, only now additional factors shaping cooperation, generosity, and forgiveness enter the analysis and the real time dynamics of how careworthiness, expected value, and perceived safety are activated is open to further analysis.

Finally, in the context of rational manipulation of game play contingencies and subsequent levels of cooperation/forgiveness, both McCullough and game play theorists need to consider two related issues: group size and problem complexity. In relation to group size, we must appreciate that revenge and forgiveness are played out in different contexts. McCullough touches upon the problem of expanding small group game solutions (e.g., tit-for-tat) to large scale issues of mass behavior and international affairs in the closing chapters of the book, but one problem for game theory currently is that simulations generally have limited applicability to the analysis of human action in a mass behavior context, particularly in situations where there are a continuum of agents, each of whom operate in different sub-groups, with different sub-cultures, different roles, and different rules governing their behavior. Consistent with McCullough's view, some of the same core principles of behavior change may be critical in shaping cooperation and forgiveness in this context - signal and activate careworthiness, expected value, and perceived safety throughout the whole social network -- but other variables also come into play, and this takes us to the second, related issue: problem complexity.

Consider the problem of achieving group consensus as to the logical influence structure of major obstacles to effective communication in a group problem solving setting [12]. Presumably, if we wanted to effectively communicate (i.e., signal and activate) careworthiness, expected value, and perceived safety throughout the whole of a social network, it would be necessary to first remove the obstacles to effective communication. How do we do this and then go from here to solve related problems, like promoting good relations between two groups who are trapped in a cycle of conflict? We need a systems science method that maps the structure of the problem and assists with the formal modeling of actions that resolve the sub-problems in the problem field. Such systems science methods are available [6, 13, 14], and have been successfully applied to problems of conflict resolution [12]. To my mind, the future of effective conflict resolution - a fundamental theme of McCullough's book - rests in the hands of those with knowledge of applied systems science.

But none of this forward thinking critical comment is designed to detract in any way from Michael McCullough's book. This is a truly an outstanding book: clear, concise, balanced, well-argued, insightful, enlightening. A must read for anyone interested in the current state of the world.


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The premise of the book is simple: Vengeance and forgiveness are evolutionary adaptations and their presence can be found in various species of living creatures, including apes, monkeys, cetaceans, birds, and, or course, humans. The book reviews all of these aspects, as well as examples of how vengeance, and forgiveness, has changed the lives of individuals and nations; it describes the necessary ingredients for the posibility of forgiveness from victims; discusses programs like: retributive justice and reconciliation programs, which have sprung in different parts of the world with great success; and, provides numerous references to research in these areas and to support the main premise. In conclusion, vengeance is not a disease, an infection, or an aberration, it is a natural process which will be present when the necessary components are not present for forgiveness to arise. We all screw up, sometimes, and need to learn how to make amends before we get our head chopped off.