Cruelty: Human Evil and the Human Brain

A review of a book on human cruelty is a daunting and anxiety-provoking task. Listening to news broadcasts on any given day, one is confronted with examples of the myriad ways in which humans can perpetrate undreamt-of barbarity upon each other.

I feared that a book examining cruelty in depth would elaborate on these acts in such a way that my dreams would be haunted for weeks.

Indeed, there is plenty in Kathleen Taylor's book to sicken the stomach and make one wonder whether we can ever gain an understanding of the baseness to which human behaviour can sink. But to dwell on specific examples is to sensationalise an excellent work that seeks to understand what makes us engage in cruelty and to pose the question as to whether we can ever stop doing so.

Drawing on her own background in philosophy and neuroscience to begin to unravel behaviour that lies between the interface of morality and science, Taylor deftly dismisses religious arguments relating to the necessity of suffering for spiritual growth and gets swiftly down to the business of providing an interdisciplinary focus on extreme cruelty.

There are books that pay lip service to interdisciplinary approaches and then there are works whose scope encompasses perspectives drawn from the world's canon. Taylor's book falls very clearly into the latter category.

It ranges through history, philosophy, sociology, psychology and neuroscience. This is the first time I have seen in the same bibliography Adolf Hitler's Mein Kampf, Noel Malcolm's excellent Bosnia: A Short History and the work of Antoine Bechara and Hannah and Antonio Damasio on the role of the orbitofrontal cortex in emotion and decision-making. Anyone who reads Taylor's book is provided with enough required further reading to last a lifetime.

The first three chapters of Cruelty examine what cruelty is, who decides what actions count as cruel and why humans act in cruel ways. She prefers the term "otherisation" to express the social gulf between "us" and "them", in which, she argues, all cruel acts are grounded.

Taylor uses research from the neurosciences to show that humans are biased towards pleasure and away from pain and that we seek out those actions that make us feel good about ourselves and avoid those that are unpleasant and aversive.

In our weakness we have a tendency to otherise, not just in times of great crisis, but in reaction to quite minor challenges to our social status, assets or sense of honour.

Taylor's arguments are supported by historical examples, but it is easy to draw parallels with contemporary strains of Western political thought that demonise our own "out" groups and make fatuous attempts founded on shifting sands to rationalise and support cruel and bellicose actions.

The middle chapters of Cruelty set about providing an understanding of how the human brain mediates actions, emotions and beliefs, and applies them to an understanding of the problems of callous and sadistic behaviour. Taylor's arguments are based on Darwinian principles in which, she argues, callousness can provide long-term benefits for group survival - but survivors of callous cruelty often resort to cruel measures themselves.

Sadism, in contrast, comes about when the distress signals that would normally inhibit acts of aggression and cruelty become associated with reward.

Philip Zimbardo, the renowned social psychologist at Stanford University, showed how easy it is to turn healthy young men into sadistic "prison guards" within a few days in his famous prison experiment.

The final chapter leaves us with a bleak and disturbing ending to Taylor's treatise: "we need wisdom and courage and the will to exert considerable effort without much discernible reward" to stop being cruel - and in humans these characteristics are in short supply.

Both lay readers and academics from a variety of disciplines will find Cruelty an absorbing and thought-provoking work. I shall be recommending it to my students on a variety of philosophy and neuroscience courses.

In fact, I would go so far as to suggest that a copy should be given to every politician elected to Parliament in the hope that gaining a greater scientific understanding of what cruelty is and why we have the capacity to perpetrate such acts will influence policymaking away from beliefs that are grounded in the demonisation of "otherness".