One of the most common objections to my position on free will is that accepting it could have terrible consequences, psychologically or socially. This is a strange rejoinder, analogous to what many religious people allege against atheism: Without a belief in God, human beings will cease to be good to one another. Both responses abandon any pretense of caring about what is true and merely change the subject. But that does not mean we should never worry about the practical effects of holding specific beliefs.

I can well imagine that some people might use the nonexistence of free will as a pretext for doing whatever they want, assuming that it’s pointless to resist temptation or that there’s no difference between good and evil. This is a misunderstanding of the situation, but, I admit, a possible one. There is also the question of how we should raise children in light of what science tells us about the nature of the human mind. It seems doubtful that a lecture on the illusoriness of free will should be part of an elementary school curriculum.

In my view, the reality of good and evil does not depend upon the existence of free will, because with or without free will, we can distinguish between suffering and happiness. With or without free will, a psychopath who enjoys killing children is different from a pediatric surgeon who enjoys saving them. Whatever the truth about free will, these distinctions are unmistakable and well worth caring about.

Might free will somehow be required for goodness to be manifest? How, for instance, does one become a pediatric surgeon? Well, you must first be born, with an intact nervous system, and then provided with a proper education. No freedom there, I’m afraid. You must also have the physical talent for the job and avoid smashing your hands at rugby. Needless to say, it won’t do to be someone who faints at the sight of blood. Chalk these achievements up to good luck as well. At some point you must decide to become a surgeon—a result, presumably, of first wanting to become one. Will you be the conscious source of this wanting? Will you be responsible for its prevailing over all the other things you want but that are incompatible with a career in medicine? No. If you succeed at becoming a surgeon, you will simply find yourself standing one day, scalpel in hand, at the confluence of all the genetic and environmental causes that led you to develop along this line. None of these events requires that you, the conscious subject, be the ultimate cause of your aspirations, abilities, and resulting behavior. And, needless to say, you can take no credit for the fact that you weren’t born a psychopath.

Of course, I’m not saying that you can become a surgeon by accident—you must do many things, deliberately and well, and in the appropriate sequence, year after year. Becoming a surgeon requires effort. But can you take credit for your disposition to make that effort? To turn the matter around, am I responsible for the fact that it has never once occurred to me that I might like to be a surgeon? Who gets the blame for my lack of inspiration? And what if the desire to become a surgeon suddenly arises tomorrow and becomes so intense that I jettison my other professional goals and enroll in medical school? Would I—that is, the part of me that is actually experiencing my life—be the true cause of these developments? Every moment of conscious effort—every thought, intention, and decision—will have been caused by events of which I am not conscious. Where is the freedom in this?

If we cannot assign blame to the workings of the universe, how can evil people be held responsible for their actions? In the deepest sense, it seems, they can’t be. But in a practical sense, they must be. I see no contradiction in this. In fact, I think that keeping the deep causes of human behavior in view would only improve our practical response to evil. The feeling that people are deeply responsible for who they are does nothing but produce moral illusions and psychological suffering.

Imagine that you are enjoying your last nap of the summer, perhaps outside in a hammock somewhere, and are awakened by an unfamiliar sound. You open your eyes to the sight of a large bear charging at you across the lawn. It should be easy enough to understand that you have a problem. If we swap this bear for a large man holding a butcher knife, the problem changes in a few interesting ways, but the sudden appearance of free will in the brain of your attacker is not among them.

Should you survive this ordeal, your subsequent experience is liable to depend—far too much, in my view—on the species of your attacker. Imagine the difference between seeing the man who almost killed you on the witness stand and seeing the bear romping at the zoo. If you are like many victims, you might be overcome in the first instance by feelings of rage and hatred so intense as to constitute a further trauma. You might spend years fantasizing about the man’s death. But it seems certain that your experience at the zoo would be altogether different. You might even bring friends and family just for the fun of it: “That’s the beast that almost killed me!” Which state of mind would you prefer—seething hatred or triumphant feelings of good luck and amazement? The conviction that a human assailant could have done otherwise, while a bear could not, would seem to account for much of the difference.

A person’s conscious thoughts, intentions, and efforts at every moment are preceded by causes of which he is unaware. What is more, they are preceded by deep causes—genes, childhood experience, etc.—for which no one, however evil, can be held responsible. Our ignorance of both sets of facts gives rise to moral illusions. And yet many people worry that it is necessary to believe in free will, especially in the process of raising children.

This strikes me as a legitimate concern, though I would point out that the question of which truths to tell children (or childlike adults) haunts every room in the mansion of our understanding. For instance, my wife and I recently took our three-year-old daughter on an airplane for the first time. She loves to fly! As it happens, her joy was made possible in part because we neglected to tell her that airplanes occasionally malfunction and fall out of the sky, killing everyone on board. I don’t believe I’m the first person to observe that certain truths are best left unspoken, especially in the presence of young children. And I would no more think of telling my daughter at this age that free will is an illusion than I would teach her to drive a car or load a pistol.

Which is to say that there is a time and a place for everything—unless, of course, there isn’t. We all find ourselves in the position of a child from time to time, when specific information, however valid or necessary it may be in other contexts, will only produce confusion, despondency, or terror in the context of our life. It can be perfectly rational to avoid certain facts. For instance, if you must undergo a medical procedure for which there is no reasonable alternative, I recommend that you not conduct an Internet search designed to uncover all its possible complications. Similarly, if you are prone to nightmares or otherwise destabilized by contemplating human evil, I recommend that you not read Machete Season. Some forms of knowledge are not for everyone.

Generally speaking, however, I don’t think that the illusoriness of free will is an ugly truth. Nor is it one that must remain a philosophical abstraction. In fact, as I write this, it is absolutely clear to me that I do not have free will. This knowledge doesn’t seem to prevent me from getting things done. Recognizing that my conscious mind is always downstream from the underlying causes of my thoughts, intentions, and actions does not change the fact that thoughts, intentions, and actions of all kinds are necessary for living a happy life—or an unhappy one, for that matter.

I haven’t been noticeably harmed, and I believe I have benefited, from knowing that the next thought that unfurls in my mind will arise and become effective (or not) due to conditions that I cannot know and did not bring into being. The negative effects that people worry about—a lack of motivation, a plunge into nihilism—are simply not evident in my life. And the positive effects have been obvious. Seeing through the illusion of free will has lessened my feelings of hatred for bad people. I’m still capable of feeling hatred, of course, but when I think about the actual causes of a person’s behavior, the feeling falls away. It is a relief to put down this burden, and I think nothing would be lost if we all put it down together. On the contrary, much would be gained. We could forget about retribution and concentrate entirely on mitigating harm. (And if punishing people proved important for either deterrence or rehabilitation, we could make prison as unpleasant as required.)

Understanding the true causes of human behavior does not leave any room for the traditional notion of free will. But this shouldn’t depress us, or tempt us to go off our diets. Diligence and wisdom still yield better results than sloth and stupidity. And, in psychologically healthy adults, understanding the illusoriness of free will should make divisive feelings such as pride and hatred a little less compelling. While it’s conceivable that someone, somewhere, might be made worse off by dispensing with the illusion of free will, I think that on balance, it could only produce a more compassionate, equitable, and sane society.