Determinism and Free Will

Brutus orchestrated a plot to assassinate Caesar. One might think that he could have done otherwise - he could have had a change of heart; he could have remained loyal to Caesar, etc. But, according to Peter Van Inwagen (a twentieth-century Philosopher), if the laws of nature that govern our world are deterministic, then Brutus could not have done otherwise.

First, let’s define our terms. Determinism is the idea that the universe unfolded in a completely predictable manner to some observer who is outside the universe. In other words, the initial state of the universe made sure that all subsequent states will occur. If you were to replay the tape of the universe, it would unfold in the same way. And this is due to the laws of physics that make sure that whatever happens will follow then and happen in the same way. We note that the predictability is to an outsider of the universe, as an agent in the universe would be able to predict its own actions and not take them, thus producing a paradox.

Secondly, the capacity to do otherwise means that a person or agent can take a different action than the one he took and have subsequent actions take place differently. So, if I raise my arm now, I could not have raised it if I wanted.

With those definitions in mind, Peter Van Inwagen’s argument is:

Suppose Determinism is true. Then, if it were true that Brutus could have done otherwise, it would be true that he could have made the laws of nature or initial conditions of the universe different. But obviously, that’s not true! None of us has the power to break laws or influence the billions-of-years-distant past! So, supposing Determinism is true; Brutus could not have done otherwise.

On the face of it, this is a sound argument. It is intuitive to us that free will rests on the possibility of being able to do otherwise than what we did. If we can’t do anything but what we have done, then we lack free will.

However, there’s an objection raised that hinges on the idea of “could have done otherwise” and whether that matters in the first place. Consider the following biblical case:

-          Cain is going to become a murderer. He is about to kill his brother Abel because the latter got the favor of God.

-          Now consider that Satan is monitoring this biblical act and can read Cain’s mind (as demons can). If Cain ever has a change of heart, then he would interfere, possess Cain and carry out the murder

In the previous case, Cain really could not have done otherwise. In either case, he was going to kill Abel, whether he wished it or not. Does that mean that Cain lacked free will? Consider the whole act unfolded without Satan’s intervention. Cain would have carried out his desire as he wished it to be.

This has been refutable of Van Inwagen’s argument about free will and determinism (you can also replace Satan with a neuroscientist that is monitoring Cain’s brain and can take swift action to control Cain).

I think there is a deeper, more nuanced argument when it comes to determinism and free will. Let’s go back to the example of Cain and Abel. In this case, the Devil won’t take any action, but God performs a micro-miracle in Cain’s head and rewires neurons so that Cain has a change of heart and doesn’t go through with killing Abel. In this case, can we say that Cain acted of his own free will? No, of course not.

I think that if determinism is true, then our brain circuitry is wired in a way that the universe is performing micro-miracles in our brain to force our desires, wishes, and decisions. Indeed, the brain is the center of decision making, and it is part of the universe. If determinism is true, then what we interpret as free will is an illusion, my writing this essay or Cain killing Abel or  Brutus plotting against Caesar are all the results of deterministic computations carried out by our brains, all of which were initiated by the initial conditions of the Universe and the Big Bang.

Indeed, this brings us back to Van Inwagen’s argument and the clause about changing the laws of nature. For the brain-computer to change the outcome of an action, then he would have to change its original programming, which means changing the initial state of the universe which partook in this programming.

To better dig into this analogy, consider a computer program simulating a basic life form. Whatever the lifeform does in the simulation will be based on the will of the programmer who wrote the simulation program. For that virtual lifeform to have free will, it would need to change the will of the programmer who is outside the computer, which is impossible.

In this essay, we presented the incompatibilism argument. It states that if determinism is true, then we can’t do otherwise. And therefore, we lack free will. I presented some counterarguments that take the form of someone can make sure that whatever we do, then the action will take place. But then went into the brain’s computational model and showed how determinism affects the brain and therefore, we are not able to do otherwise by design and free will is an illusion if determinism is true.

I will end on this note, the fact that determinism forces the brain to be a computer with deterministic outputs shows that something is wrong with the idea of the determinism of the universe in the first place. If I want to lift my hand at will, I can. I don’t see how my will is an illusion there. But determinism forces it to be.