Book review: Moral Brains

An Epiphllum (leaf cactus) flower

Moral Brains: The Neuroscience of Morality bills itself as a brief review of the state of research into morality (Oxford University Press, 2016). If this is only a brief introduction, it is nonetheless brilliant. This is the first book this reviewer is aware of that shows how pure philosophical reasoning can effectively critique empirical science and point to new lines of research. The philosophers are up to speed on the empirical data and they powerfully integrate it with philosophy.

The book is edited by S. Matthew Liao at the Center for Bioethics at New York University. Liao’s book describes the current four major competing models of moral judgment. Some chapters are written by, and/or commented on by proponents of three of the four main models. Others directly critique one or more of the models and three chapters are rebuttals by the researcher credited with starting the neuroscience of morality or key proponents of one of the models. The book reviews 15 years of data and thinking about the neuroscience of morality. The authors are all thought leaders or highly respected in the field.

The book’s content focus includes considering emotion vs. reason, and philosophical lessons so far, with their implications for future research. This review can only hint at the richness, depth and clarity of the thinking expressed in Moral Brains. This short book review cannot do justice to what’s there.

The models: These models of moral judgment reflect the early state of moral neuroscience.
1. Emotion results from judgment:
Reasoning/unconscious rules → judgment → emotion
2. Emotion cause judgment: Emotion → judgment → reasoning
3. Emotion and reasoning cause judgment (dual inputs): Reasoning + emotion → judgment
4. Judgment contains emotion: Judgment containing emotion ↔ reason

Consideration of emotion or reason as the source of morality is ancient, but the modern debate is significantly framed by David Hume (1711-1776) and Immanuel Kant (1724-1804). Hume argued that reason is a “slave to the passions” and morality is bound up in emotion somehow. By contrast, Kant argued that morals are derived mostly from reason, usually thought of as conscious thinking. By the time one gets to the end of Liao’s book, it is clear that what’s the best of the four models is open to debate. Nonetheless, the balance of what Liao and the other authors have to say tips things (i) somewhat in favor of Kant and the ‘moral judgment contains emotion’ model, and (ii) modestly against the reason and then judgment causes emotion model.

Referring to brain scan data, Liao observes that “Every single neuroimaging study of moral cognition that I know concurs on one point: moral judgments regularly engage brain structures that are associated with emotional processing.” Obviously that isn’t proof, but it is consistent with some significant role for emotion.

The data against the emotions are moral judgment outputs seems rather convincing. According to author Jesse Prinz (chapter 1): “Numerous studies have shown that induced emotions can influence our moral judgments. . . . . happiness increases positive moral judgments and anger brings them down. The pattern of emotional impact is highly specific. Different emotions have distinctive and predictable contributions.” That makes emotions look at least as much like a moral judgment input as an output. Prinz is a key proponent of the judgment contains emotion judgment model.

A recurring Moral Brains theme questions if judgments based on conscious reason are more reliable or ‘truth seeking’ than emotion-based ones. That is open to debate. An interesting observation is that psychoactive drugs can change moral judgments.

Other insights include fairly convincing arguments and some evidence that reason isn’t only a conscious mental process. Previously many philosophers and scientists believed that reason was largely conscious (> 95% ?), but that belief is in question.

An assertion in Liao’s book is this by Walter Sinnott-Armstrong (chapter 14): “One of the most important lessons from the first decade of research in moral neuroscience is that morality is not unified in the brain or anywhere else.” Sinnott-Armstrong points out that, (i) morality isn’t located (unified) in any specific part of the brain, (ii) morality isn’t unified by content, e.g., it’s not just being about what’s right and wrong, and (iii) morality isn’t unified by its function, e.g., it’s not just being about using customs and values to guide social conduct.

At this point, the reader might see a contradiction: Liao says emotion-related areas of the brain are involved, but Sinnott-Armstrong says there’s no unity in terms of brain location. There is no contradiction. Although emotion processing centers may often (always?) be involved, there’s more to it than that. Other areas are likely also involved, e.g., as in the judgment contains emotion model where reason also influences moral judgment. To get to that belief, just consider the factor of time. Yes, people often make snap moral judgments. However, when given some time for reason and/or intuition, even a few minutes, moral judgments sometimes drift or change completely.

The neuroscience of morality probably still has at least 2-3 decades of research ahead of it before some basic issues begin to resolve into at least modest clarity. Maybe the most fundamental unanswered question is whether empirical neuroscience can ever lead to normative conclusions about what’s right and wrong. That’s a tough question. Is there a philosopher in the house?

NOTE: From this reviewer’s point of view, politics is more a matter of intuition-emotion and personal morals and identity than fact and logic. Reading Liao’s book reinforces that belief. It provides a current, broad knowledge basis for it. People interested in politics who read this book will easily see direct relevance to real world politics and politicians.

'Generous Gift' hybrid

B&B orig: 5/15/17