Behave: The Biology of Humans at Our Best and Worst

Early on in Behave, Sapolsky eschews the concepts of right and wrong, good and evil, and prosocial and antisocial in favor of two “concepts that truly defy brevity” (20): best and worst. Sapolsky does so because he writes from the perspective that, though science can tell us much about the reasons we behave in one way or another, it cannot tell us if these behaviors are innately good or bad. This depends on context.

The argument that right and wrong depend on context emerges from Sapolsky’s career as a scientist, but it is indebted to an intellectual history primarily outside of science. This is the field of normative ethics, a genre of philosophy that deals with the moral quality of behaviors. The question of what is right and wrong is one of the earliest strains in philosophy, with different arguments throughout the ages generally categorizable into two competing perspectives: deontological ethics and consequentialist ethics.

Deontology, from the Greek δέον (deon): “rule/duty,” and λόγος (logos): “study,” is the idea that morality is and should be bound by inviolable rules. In this framework, the morality of an act is innate to the act itself depending on whether the act breaks a moral rule. For instance, one moral rule is that it is wrong to kill. Therefore, any act of killing is immoral, irrelevant of its context. This concept of morality is expressed early in recorded history in certain doctrinal religious perspectives on morality, such as the Ten Commandments. Within modern philosophy, deontology is largely traced to Immanuel Kant, who believed the highest good is a good in itself, meaning a goodness with intrinsic good quality. Acts are moral in a Kantian framework when they act in duty to the good.

Consequentialism, also referred to as utilitarianism, is the alternative to the deontological idea. It argues acts are morally correct or incorrect not based on the nature of the act but on the act’s consequence, or utility. For instance, it is morally incorrect to kill in murder because its consequence is needless death, but it is morally correct to kill in certain wars because its consequence is protecting your homeland. Early philosophical incarnations of consequentialism include classical Greek philosophy, which saw virtue as based upon living one’s best life (including killing in war). Within modern philosophy, consequentialism is largely associated with Jeremy Bentham, who coined the term.

Sapolsky tangles with these two moral philosophies throughout Behave, constantly landing on the consequentialist perspective. His morally ambiguous description of killing Hitler, which incites the book, or his description of the movement of fingers and their varied consequences at the beginning of Chapter 1 (see Quote 4) express this view. The debate between deontology and utilitarianism is most specifically discussed regarding the trolley problem in Chapter 13. Put into action on this problem, a consequentialist would consider it acceptable to kill one to save five (a net profit of four lives) while a deontologist would be forced to do nothing (killing five through inaction). Sapolsky’s core point in this moment is that the human brain is capable of both, depending on which of its specific structures are activated: “When deontologism and consequentialism contemplate trolleys, the former is about moral intuitions rooted in the vmPFC, amygdala, and insula while the latter is the domain of the dlPFC” (505). What activates these regions? Us, and our choices, based on our environment, and our genetics, and the environment of our genetics, and our culture, and endless other contextual factors. Morality does not just depend on context; it depends on varied interdependent contexts.