The concept of free will can be defined as the ability to arbitrarily make a choice. It is antithetical to the concept of determinism, where all events are simply the effects of causes and therefore, given a state of the universe and complete knowledge of how the universe works, one could determine all future events.
Thinking at a surface level, many of us would probably claim that we have at least some amount of free will, citing decisions we’ve made from as small as what size of coffee to purchase to as big as who to choose as a life partner. Others would say that one’s actions are not in fact freely made but simply the culmination of past events. Still others would argue that our reality involves a bit of both—that is, there exists a small amount of free will but our decisions are largely influenced by things outside our control.
Philosophers have long debated free will versus determinism by attempting to answer the question, “does free will exist?” But here we will explore a more fundamental question, which is “can free will exist?” The difference between these two questions is subtle but important. The former has a tendency to devolve into philosophical musings regarding the implications of the existence of free will versus not. The latter focuses discussion to logical reasoning devoid of emotionally-charged biases, which one is apt to bring into the picture when moving too quickly to the implications of the answer rather than the answer itself.
For the sake of simplicity, focus will be kept on the idea of humans possessing free will (though one could easily have the same discussion with regard to other entities). Additionally, the answer being sought is a simple yes or no. That is, can free will exist in any capacity (however small or large) or not?
Alice is a 17-year-old girl about to graduate high school. One evening at the dinner table, her mother and father discuss with her that it’s time to start applying to universities. They inform her that they have saved enough money in order to fully pay for her degree, but it is up to her to decide which university she wishes to attend.
After applying to several universities, Alice is accepted by both Harvard and Stanford. Alice now has a choice—a very simple choice from a mathematical perspective considering there are only two options. And yet a not so simple choice from the perspective that her life for the next four years will be very different depending on which university she chooses—different classes, friends, and experiences. Even the future of her entire career may be dependent on which school she chooses.
Let’s focus our attention on the particular moment where Alice, having thought long and hard about the choice in front of her, is sitting on her bed at home with both acceptance letters in front of her. This is the exact moment just before she makes her decision. Now imagine that right at this point we made an exact copy of the entire universe. So we now have two completely identical universes, all with the exact same history of events, arrangement of particles and energy, etc. There are zero differences between these universes.
Let’s first consider the notion that free will does exist. In that case, Alice might choose Harvard in universe A and Stanford in universe B because the choice is entirely up to her and therefore there’s no way to determine which she will choose in either universe.
Suppose she does choose Harvard in universe A and Stanford in universe B. Then one of two things must be true: either 1) universe A and universe B are not actually identical, or 2) there is something external to each universe that has influence on them. We’ve already established that both universes are completely identical, so situation 1 cannot be true. That leaves situation 2.
Many people would stop here, citing situation 2 as true due to their belief in the existence of a god or gods, the human spirit or soul, etc. Or the more scientifically-minded might attempt to explain it by citing “quantum physics” or some related scientific concept as the explanation for non determinism (as if anyone who throws quantum physics out as justification for an argument actually understands any of it).
But none of these concepts actually explains anything at all. Perhaps humans do possess a spirit and it is superhuman in nature, capable of things that the physical part of humans is not. But what would give such a thing the ability to make arbitrary choices? A spirit must exist in some reality, however different it may be from our own. And if such a reality provides the ability to make truly arbitrary, unimpeded choices, where does it derive such freedom? Any attempt to answer this question will result in a similar answer as what led to the question in the first place. Which then leads to the same question again, and so on.
The same goes for the notion that something such as the supposed random movements of fundamental particles of the universe or the uncertainty principle can serve as the foundation for free will. Putting aside discussion on whether or not the concept of “random” actually makes any sense, the existence of true randomness would only dismiss determinism. But the non existence of determinism does not equate to the existence of free will. A reality in which every human decision is the result of something random is very different from one in which humans possess the ability to choose. To put that in clearer terms, Alice being forced to use the outcome of a coin toss as the determining factor for which university to attend would not be free will.
Let’s now explore the idea that free will does not exist. What does that mean? It means that Alice actually doesn’t have a choice, but instead the “choice” she ends up making is really just the culmination of everything that happened in the past. Or in more scientific terms, her action is dictated by the state of matter and energy in the universe at that point in time.
If free will does not exist, then her decision in both universes will always be the same. And in fact, at any moment in the history of the universe, if you were to make an identical copy of that universe, the future in both those universes would always play out exactly the same.
And so we arrive at a rational paradigm, which unlike one that claims free will as part of reality does not leave us with unexplainable concepts which only serve to deflect the question of where free will originates. The universe may be so complex that although its current state dictates future states with certainty, humans might never be able to predict those future states. And yet such is the explanation for reality with the fewest assumptions and unanswered questions.
Attempts to claim the existence of free will as a reality are usually justified by belief in god(s), spirits, randomness, or something “out there”. But even putting aside debate about whether any of those things actually exist and just assuming that one or more of them does, we realize that they can only serve to remove the question of where free will originates by one level of reasoning. As soon as we begin to ponder the concept of a separate reality that can influence ours, we must then ask the same questions of that separate reality. And then we realize that we have in fact answered nothing at all.
If we resort to the notion that this other reality is simply incomprehensible to humans, we have still answered nothing. We are simply attempting to explain phenomena by introducing unexplainable phenomena. And such is no explanation at all.
A lack of free will’s existence—however disconcerting the implications might be for some—does not leave us with any unanswered questions about the fundamental nature of our reality. It is simple to reason about and introduces no unprovable ideas, and therefore we must conclude that it is the most likely explanation for the reality we live in.