Cognitive Science Transforms Moral Philosophy

For 2500 years moral philosophy was entrusted to philosophers and theologians. But in recent years moral philosophers who are also cognitive scientists and cognitive scientists with a sophisticated mastery of moral philosophy have transformed moral philosophy. Findings and theories from many branches of cognitive science have been used to reformulate traditional questions and to defend substantive views on some of the most important moral issues that face contemporary societies. In this new synthesis, the cognitive sciences are not replacing moral philosophy. Rather, they are providing new insights into the psychological and neurological mechanisms underlying moral reasoning and moral judgment, and these insights are being used to construct empirically informed moral theories that are reshaping moral philosophy.

Here’s the backstory: From Plato onward, philosophers who were concerned with morality have made claims about the way the mind works when we consider moral issues. But these claims were always speculative and often set out in metaphors or allegories. With the emergence of scientific psychology, in the 20th century, psychologists became increasingly interested in moral judgment and moral development. But much of this work was done by researchers who had little or no acquaintance with the rich philosophical tradition that had drawn important distinction and defended sophisticated positions about a wide range of moral issues. So philosophers who dipped into this work typically found it naïve and unhelpful.

At the beginning of the current century that began to change. Prompted by the interdisciplinary zeitgeist, young philosophers (and a few who weren’t so young) resolved to master the methods of contemporary psychology and neuroscience and use them to explore questions about the mind that philosophers had been debating for centuries. On the other side of the disciplinary divide, psychologists, neuroscientists and researchers interested in the evolution of the mind began to engage with the philosophical tradition more seriously. What began as a trickle of papers that were both scientifically and philosophically sophisticated has turned into a flood. Hundreds of papers are published every year, and moral psychology has become a hot topic. There are many examples of this extraordinary work. I’ll mention just three.

Joshua Greene is in many ways the poster child for the new synthesis of cognitive science and moral philosophy. While working on his PhD in philosophy, Greene had the altogether novel idea of asking people to make judgments about moral dilemmas while in a brain scanner.

Philosophers had already constructed a number of hypothetical moral dilemmas in which a protagonist was required to make a choice between two courses of action. One choice would result in the death of five innocent people; the other would result in the death of one innocent person. But philosophers were puzzled by the fact that in very similar cases people sometimes chose the to save five and sometimes chose to let the five die.

What Greene found was that different brain regions were involved in these choices. When the five were saved the brain regions involved were thought to be associated with rational deliberation; when the five were not saved, the brain regions involved were thought to be associated with emotion.

This early result prompted Greene to retrain as a cognitive neuroscientist and triggered a tsunami of studies exploring what is going on in the brain when people make moral judgments. But though Greene became a cognitive scientist, he was still a philosopher, and he draws on a decade of work in moral psychology to defend his account of how moral decisions that divide groups should be made. Greene illustrates the way in which moral philosophy can be transformed by cognitive science.

If Greene is the poster child for the new synthesis, John Mikhail is its renaissance man. While completing a philosophy PhD, he spent several years studying cognitive science and then got a law degree. He’s now law professor where his areas of expertise include human rights law and international law.

Drawing on the same family of moral dilemmas that were center stage in Greene’s early work, Mikhail has conducted an extensive series of experiments that, he argues, support the view that all normal humans share an important set of innate moral principles. Mikhail argues that this empirical work provides the much needed intellectual underpinning for the doctrine of universal human rights!  

And finally an example—one among many—of the new questions that the new synthesis has enabled us to see. Recent work in psychology has revealed that we all have a grab bag of surprising implicit biases. Many people, including people who support and work hard to achieve racial equality, nonetheless associate black faces with negative words and white faces with positive words. And there is a growing body of evidence suggesting that these implicit biases also affect our behavior, though we are usually completely unaware that this is happening.

Moral philosophers have long been concerned to characterize the circumstances under which people are reasonably held to be morally responsible for their actions. Are we morally responsible for behavior that is influenced by implicit biases? That’s a question that has sparked heated debate, and it is a question that could not have been asked without the new synthesis.

Will all this still be news in the decades to come? My prediction is that it will. We have only begun to see the profound changes that the new synthesis will bring about in moral philosophy.