The discrediting of economics is the second reason for the success of Brooks’s book with its emphasis on the power of emotion and intuition and its debunking of the power of reason devoid of sentiment. Yet who—aside from one or two recent Nobel Prize–winning economists—has ever imagined humans to be calculating machines? After all, classical economics fully acknowledged the central role of emotion in human conduct. It was not for nothing that Adam Smith entitled his treatise on ethics The Theory of Moral Sentiments. Brooks acknowledges that there are strands in Enlightenment thinking that stress the limitations of reason. As he writes, “If you want to put the philosophic implications in simple terms, the French Enlightenment, which emphasized reason, loses; the British Enlightenment, which emphasized sentiments, wins.” Brooks may overpraise British Enlightenment thinkers—who include Jeremy Bentham, the founder of utilitarianism and a thoroughgoing rationalist—but he is right in noting that the Enlightenment has not entirely neglected the limits of reason. Regarded by many as the supreme Enlightenment philosopher, Immanuel Kant was quite explicit in stating that there are questions that human reason cannot answer. One could go back further and note that Aristotle—commonly regarded as one of the greatest Western rationalists—insisted that virtuous conduct was a matter of habit and character just as much as rational deliberation.

Of course there is more to Brooks’s message than these familiar observations. The core of Brooks’s argument is his claim that the forces controlling human behavior are not just nonrational, they are unconscious—and can be controlled. As he puts it, “The central evolutionary truth is that the unconscious matters most.” Significantly, Sigmund Freud appears hardly at all in the four hundred or so pages of this treatise on the role of the unconscious in social life. According to Brooks, this is because Freud has been superseded:

When Freud came up with his conception of the unconscious, it had a radical influence on literary criticism, social thinking, and even political analysis. We now have a more accurate conception of the unconscious. But these findings haven’t yet had a broad impact on social thought.

Freud’s view of the unconscious has been rendered obsolete by the new cognitive science: “Brain research rarely creates new philosophies, but it does vindicate some old ones.” It is true that Freud’s theorizing was not exactly scientific—as he accepted in some of his later work. But I suspect it is not because Freud’s thinking has been scientifically superseded that Brooks is so quick to dismiss it. Rather, it is because Freud did not share Brooks’s hopes of happiness. The greatest twentieth-century Enlightenment thinker had more than a little in common with the ancient Stoics. He was not preaching anything resembling Brooks’s sunny optimism when he wrote to a patient,

I do not doubt that it would be easier for fate to take away your suffering than it would for me. But you will see for yourself that much has been gained if we succeed in turning your hysterical misery into common unhappiness. Having restored your inner life, you will be better able to arm yourself against that unhappiness.

Freud never imagined that his research into the unconscious mind would open the way to happiness. Instead, it could be used to fortify the mind against unhappiness, which the founder of psychoanalysis accepted as the normal human experience.

In stark opposition to Freud, Brooks thinks he has found in the unconscious something like a technology of human fulfillment. “The central humanistic truth,” he writes, “is that the conscious mind can influence the unconscious.” Because of the advance of science, we can now do what Freud believed was impossible—take control of the unconscious mind, so that it functions to promote happiness:

We are living in the middle of a revolution in consciousness. Over the past few years, geneticists, neuroscientists, psychologists, sociologists, economists, anthropologists, and others have made great strides in understanding the building blocks of human flourishing. . . . The unconscious parts of the mind are most of the mind—where most of the decisions and many of the most impressive acts of thinking take place. These submerged processes are the seedbeds of accomplishment.

It is not just individuals who can reshape their lives by tapping the power of the unconscious. By applying these new findings, governments can enable society to function more harmoniously. The “big policies”—of education reform, poverty alleviation, democracy promotion—pursued over the past generations failed, Brooks believes, because they did not harness the unconscious. But for Brooks they failed for another reason, too: they did not understand that humans are above all social animals.

Again, this is hardly news. David Hume criticized Thomas Hobbes for having a view of human beings that was asocial, while Aristotle pronounced members of our species to be political animals (where “political” meant something more like what we now mean by “social”). It is only because economists have in recent times operated with an abstract conception of human motivation as maximizing the satisfaction of individual preferences that the idea that humans are au fond social beings seems at all striking. Here as elsewhere the illusion of novelty is kept alive by a loss of memory. No one who had read and digested Adam Smith or Edmund Burke—or indeed John Maynard Keynes—could possibly imagine that the life of man would ever be carried on by unaided reason, or believe that humans were anything other than quintessentially social. Only those who have forgotten most of the Western tradition could find Brooks’s propositions arresting or in any way instructive.

ONE MIGHT be tempted to say that the political success of Brooks’s book is testimony to the callowness of our leaders, who have lost touch with the intellectual traditions that shaped Western cultures. This would be a little unfair, for what our rulers have to cope with is a larger loss of continuity in society. The deep changes that go with globalization have left governments depleted of authority. One response is a more modest conception of government: let it attend to the framework in which society does its business—including dealing with social problems—while leaving that business largely to voluntary organizations. A view of this kind is congenial to politicians at a time when resources are tight and the scope of state action is limited. (In Britain, it is the necessity of spending cuts that drives Cameron’s otherwise inchoate “big society” program, based as it is on empowering individuals and communities in order to lessen the burdens on government.) But this does not solve the problem of authority. Governments may decide to delegate to society the task of promoting the good life. But they will still find themselves—even in the very act of devolving its pursuit—having to take a view on what the good life consists of. How do our rulers decide what values to promote?

At this point we can discern a third factor in the success of Brooks’s book: the fashionable cult of science. Over the past few years, a succession of writers has claimed that science can instruct us as to how to live. Sam Harris’s The Moral Landscape: How Science Can Determine Human Values shares with Brooks the faith that what humans need in order to flourish is a matter that can be decided by scientific investigation. For Harris, the moral quandaries of the past were the result of ignorance; now that science has revealed the “moral facts” of human nature there is little room for doubt in ethics, since knowledge can replace faith and intuition in settling disputes about the essence of human well-being. Without emulating Harris’s dogmatism or sharing his enmity toward religion, Brooks also seems to believe that science has made these ethical dilemmas of the past redundant. Like Harris, he is sure that human progress will continue, and even accelerate, as long as people and governments are prepared to make use of the results of advancing scientific knowledge.

There are several problems with this view. If there are moral facts, the ethical ambiguity of science must be among the most important of them. It may be true that humans cannot flourish under tyranny, at least of a severe kind; but if the realistic alternative to such tyranny is anarchy, which also thwarts any prospect of human flourishing, there is a dilemma that no scientific advance can resolve. More importantly, there is no reason to assume those who know the human cost of tyranny will cease being tyrannous. The knowledge provided by cognitive science and evolutionary psychology—the disciplines in which those who worship at the altar of science have the most faith—is no different from any other kind of understanding: it can be used for all manner of purposes, including the most atrocious. The Nazis understood the workings of crowd psychology better than almost anyone at the time; if they had remained in power long enough to benefit from scientific advance, their ability to perpetuate their peculiarly horrible form of tyranny would undoubtedly have been improved upon. Contrary to postmodern relativists, the growth of human knowledge is a fact. But that fact does not make human beings any more likely to be virtuous, or rational. However fast and far science may advance the dilemmas that beset us, ethics will remain as problematic as before. Indeed, since the increase in knowledge enlarges the power to do evil, these dilemmas may be more formidable.