Determinism ♥ Free Will

A Teenager’s Dilemma

I was a teenager in the public library, reading about the determinism “versus” free will paradox. The idea that everything I did was inevitable bothered me, until I ran across this thought experiment:

Suppose I have a choice between A and B. I feel myself leaning heavily toward A. So, just to spite inevitability, I’ll choose B instead! Seems too easy. But then I realize that my desire to spite inevitability just made B the inevitable choice. So now I have to choose A to avoid the inevitable. But wait, now A is inevitable again … it’s an endless loop!

No matter what I choose, inevitability always switches to match my choice!

Hmm. So, who or what is controlling the choice, me or inevitability?

There is an optical illusion called the “figure-ground” illusion. It’s a black and white picture that changes. You’ll either  see two faces or you’ll see a vase. If you stare long enough, you’ll see one picture, then the other. So, what is it a picture of, two faces or a vase?


Determinism asserts that objects and forces within our universe behave rationally, reliably, and predictably. By “rationally” we mean that there is always an answer to the question, “Why did this happen?”, even if we can’t find that answer.

This means that we may, by observation and experiment, discover the causes of events that affect our lives. And, by understanding their causes, we may predict and even control these events.  For example, by understanding the causes of specific diseases, we can successfully avoid, treat, or cure  many illnesses.


Nobody really knows what an “indeterministic universe” would be like. If objects were constantly popping into and out of existence, or if gravity erratically switched between pulling things one moment to pushing them the next, then any attempts to control anything in our lives would be hopeless. In such a universe,  we could not reliably cause any effect, which means we would not be free to do anything! Fortunately, that is not the case.


Any behavior that can be described in terms of reliable causation is “deterministic”.

Physics appears deterministic, for the most part. You drop an egg and it falls to the floor and breaks. It never floats to the ceiling (unless you’re orbiting in space). But there are some areas of physics, like Quantum Mechanics, where we cannot yet explain the causes of certain effects. And there are other areas, like weather forecasting, where we know all the causes, but the complexity of their interactions hampers reliable prediction beyond a few days.

Human behavior also appears to be deterministic. Unlike inanimate objects, living organisms behave purposefully to survive, thrive, and reproduce. Species with advanced intelligence can imagine different ways to accomplish this purpose and then choose the option they feel is best.

Because our purpose and our reasons are causes, our choosing is a deterministic process. Given the same person, the same circumstances, and the same problem, they will reliably make the same choice. If the choice is different, then the person, the circumstances, or the problem has changed in some way.

Willful Objects 

It is important to note that determinism does not actually do anything. It is not itself an object or a force, but rather a belief that the behavior of objects and forces is reliable. Only real objects and forces actually do things in reality.

Objects include everything from the smallest quark to the largest galaxy. Most objects are inanimate. They behave passively, interacting according to the laws of physics.

Living organisms, on the other hand, behave purposefully. From the amoeba to the porpoise, each life form seeks what it needs to survive, thrive, and reproduce. We could call these built-in drives a kind of “biological will”. Most species act upon these drives instinctively. The natural laws that govern living organisms are discovered by the life sciences, including biology, genetics, and physiology.

Intelligent species like our own can behave deliberately. An evolved neurological system enables imagination, evaluation, and choosing.  We can imagine different ways to accomplish our purpose and choose the one that seems best. To understand the behavior of intelligent species requires the social sciences, like psychology, sociology, and ethology.

No, it’s Not Just Physics

The notion that “everything is physics” is misguided. Physics can explain why the apple fell on Newton’s head, but not why it ended up in Johnny’s lunch box fifty miles from the tree. For that you need the life sciences and the social sciences.  Each science deduces its laws from the behavior of the class of objects that it observes.

It is not that any laws of physics are ever broken. It’s just that the laws of physics do not cover everything. For example, a driver comes to a stop at a red light. Physics cannot explain why this happened, because the laws governing that action are decided by society, and published by the Department of Motor Vehicles, not the physics department.

Yes, Virginia, They Are Compatible

When a person decides for themselves what they will do, according to their own purpose and their own reasons, we call the deliberation process free will. This distinguishes it from cases where a person is coerced, or unduly influenced (e.g. hypnosis, brain tumor, authoritative command), to act against their will. In those cases their will is subject to the will of another, or to the undue influence, and it is not free.

Our choices are never uncaused. If you ask someone why they chose A instead of B, they will gladly give you their reasons. For an intelligent species, reasons are causes. So a choice that we make of our own free will is also the result of reliable cause and effect. Our choice is, at least in theory, predictable by anyone with sufficient knowledge of how we think and feel.

Both facts, autonomy and predictability, are simultaneously true. There is no conflict between (a) the fact that it was you and (b) the fact that you were behaving predictably.


A corollary of reliable causation is universal inevitability. If every event is reliably caused, and every cause is itself an event that was also reliably caused, then it follows that every event is the inevitable result of prior events. Therefore the past could not have been different from what it was and the future can only turn out one way.

This is not an inevitability that is “beyond our control”, but rather one which incorporates our control in the overall picture of causation.

Like determinism, inevitability is not an object or a force. Inevitability cannot cause anything to happen. Only objects and forces actually cause anything. Inevitability simply follows logically from the reliability of their behavior. For example, when a person makes a deliberate choice, the process of deliberation is the final responsible cause of what they do.

We are physical objects, living organisms, and an intelligent species. When we choose to act, we are also forces of nature. Within the domain of human actions, our choices causally determine what inevitably happens.

The Illusion of Constraint

There is some confusion about this. Some people insist that to be “truly” free, one must be free of causal necessity (inevitability). But “freedom from causation” is an oxymoron, because without reliable cause and effect, we cannot reliably cause any effect. We would have no freedom to do anything at all! Thus it is irrational to require any use of the term “free” to imply “freedom from causation”.

The most meaningful and relevant cause of our choices is who and what we are. We are our genetic dispositions and our life experiences. We are our beliefs and our values. We are our thoughts and our feelings. We are our memories and our habits. We are our imagination, our judgment, and our choices. These are not external forces acting upon us against our will. They are us.

The fact of autonomy and the fact of inevitability are, again, simultaneously true. It is actually us, and our choices, that determines what we inevitably do. And what we will inevitably do is exactly identical to us just being us, doing what we do, and choosing what we choose.

That is not a meaningful constraint. It is not something that anyone can or needs to be “free of”.


We’ve known that our mental processes occur within our brains as far back as Hippocrates. Prior to 400 BC, he observed personality changes in patients with certain head injuries¹.

Research continues as to how the process of choosing happens. Some of it happens within conscious awareness and some happens below the surface. Many different areas within our brain perform a variety of special functions that support our mental processes². But what remains constant, since Hippocrates, is that it is ultimately us, as a whole person, making a choice and explaining it to ourselves and others.

When people suggest that free will is an “illusion”, they are actually referring to “freedom from causation”, which we’ve already discussed above.

But the mental process of choosing is not an illusion. It is an empirical event occurring in our brains that can be observed with a functional MRI.  And whether we made that choice ourselves, or someone else coerced or manipulated us to act against our will, is also a matter of empirical fact.


Predetermination suggests there is some rational force at work, deliberately planning how everything will work out. It is a rather quirky and anthropomorphic way of viewing universal inevitability. But, again, it is a concept, and not a cause.

There is a window of meaningful and relevant causation of an event. As you move backward in time through the prior causes of prior causes, each cause becomes less direct and more coincidental to the event.

I’m sitting in a room with a bowl of apples. I’m feeling hungry and I decide that now is a good time for a snack. So I eat an apple.

The Big Bang did not have me, or the apple, in mind when it burst into a new universe. The Universe, the Solar system, and the Earth had no interest in the apple-eating event. They were, of course, prerequisites for there being a me, and an apple, in the first place, but none of them had any meaningful role in causing this event.

In fact, no prior cause that had not first become me had any influence upon me eating the apple. I had learned previously that there were benefits to eating more fruit and less sweets. But it was only after I had incorporated that viewpoint into my own values that it could affect my behavior.

The hunger was me. Without some sense of a need for food, a species goes extinct. Probably many mutant variations lacking that sense came and went. So hunger is a necessary and integral part of me.

The choice to satisfy that hunger now, rather than waiting till later, was my own choice, based on a calculation of several factors, like what I was currently doing versus the strength of the urge to eat.

There was no single event during the Big Bang that directly links to my eating the apple. Prior events may set the stage, but the script is written by me. I am the source of its meaning.


Thinking about reliable cause and effect in an abstract way leads us to the logical conclusion of universal causal inevitability. But we need to remember that this abstract model includes us, and our decisions, as part of the overall causation. Our experience of choosing is a real, empirical event. It is just as real as the gravity that curves the path of the Earth around the Sun. Without gravity, things would be quite different. The same is true of a universe without us making choices. We cause stuff. We make stuff happen. We’ve walked on our Moon and raised the temperature of our planet. Reliable causation does not enslave us, it empowers us.


1 Graziano, Michael S. A.. Consciousness and the Social Brain. Oxford University Press.

2 Michael S. Gazzaniga, “Who’s in Charge? Free Will and the Science of the Brain”
Copyright 2011, HaperCollins Publishers