Free Will and Modern Science

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While it may require an uncomfortable amount of effort due to such a long break, the reader should try to recall where this blog left off in its series on free will. In the case that the reader has failed to achieve this, let me 'splain. No, there is too much. Let me sum up. Most recently in our epic, we have seen that the libertarian must come up with some additional factor in order for her views to be coherent, and avoid accusations of randomness or arbitrariness. We have also seen the Cartesian Dualist and Kantian Noumenalist make valiant attempts to discover such a model, only to fail splendidly. At this point, the Agent-Causalist entered the story, boasting of a model which would at long last quiet the foes of libertarian freedom forever, and loosen the shackles of determinism. Our hero began constructing his model, which holds that choices are made when an agent immanently causes an action. Such an action, then, would not have been caused by circumstances, events, or states of affairs, but directly by the agent. The Agent-Causalist insists that agent-causation is unique from event causation in the sense that it is neither determined, nor random. But this appears to set the free agent up as some sort of mysterious Unmoved Mover, like God, and this fact has not been lost on critics; they have been quick to point out that until the Agent-Causalist can explain more about the nature of agent-causation, it is no less mysterious than the models of the Body-Mind Dualists, or the Kantian Idealists.

Altogether, it seems that libertarians have not done a good job of explaining how their views of free will can be reconciled to modern science. This is one reason why determinism has become so popular-- right or wrong, we understand how mechanistic causes and effects work, so the view is not as mysterious. But all the so-called extra-factors appealed to by libertarians have not had much success doing this. In the last chapter of Robert Kane's A Contemporary Introduction to Free Will that I will be posting on, Kane attempts to reconcile libertarian free will and modern science, as I will summarize.

Quantum Mechanics, Chaos Theory, and the Brain

Most philosophers will agree that for free will to exist in a libertarian sense, there must be genuine indeterminacy in some aspect of the universe. But it won't help us if the indeterminacy exists out of the context of our every day lives, will it? Indeterminate outcomes in the center of a black hole on the other side of our event horizon will not work towards our having free will. Rather, there needs to be indeterminacy in some aspect of the physical world which is associated with our decision making-- like in the human brain. It has not been uncommon for philosophers and scientists to appeal to Quantum Indeterminacy in the brain to meet this requirement. The idea would go something like this: it is well established that there is an apparent incompleteness in descriptions of physical systems at the quantum level. This manifests itself in uncertainty of measurements of observable phenomenon-- as opposed to a physicist being able to calculate the exact position of an electron orbiting an atom with a specific momentum, she can only figure a probability distribution of where the electron would most likely be. (There is, of course, disagreement over whether this is a real/ontic indeterminacy or an epistemic one-- that is, does the probability distribution reflect a real indeterminacy in the physical universe, or is it merely a limit of human's ability to accurately measure or calculate at present? There are many interpretations of quantum mechanics which support the idea that indeterminacy is a very real thing, and there is even some research which lends support to this idea. While there is some disagreement, let's simply assume that quantum indeterminacy is a real phenomenon for the sake of this post.) To quote Kane:

We know that information processing in the brain takes place through the firing of individual neurons or nerve cells in complex patterns. Individual firings of neurons in turn involve the transmission of chemical ions across neuronal cell walls, stimulated by various chemicals, called neurotransmitters, and by electrical stimuli coming from other neurons. Some neuroscientists have suggested that quantum indeterminacies in the transmission of these chemical ions across the cell membranes of neurons might make the exact timing of the firings of individual neurons uncertain, thus introducing indeterminism into the activity of the brain and making "room" for free will.1

The problem here is that it is also well known that when a large number of particles is involved, quantum indeterminacy is "damped" out "and would have negligible effects on the larger activity of the brain and body." So perhaps quantum effects in the brain will do the libertarian no good after all. Or at least not alone. But what about when coupled with Chaos Theory? You've probably heard Chaos Theory described as the so-called "Butterfly Effect." The idea is that there may be very large consequences of seemingly small actions; a butterfly flapping its wings could eventually cause a hurricane in some far off region of the world. In slightly more scientific terms, Chaos Theory has to do with how sensitive some systems can be to slight differences in initial conditions. A tiny change in the initial conditions of a system-- small enough, perhaps, to be beyond the precision of human instruments-- may cause very large differences in outcome. There is actually evidence that chaos is utilized in at least some types of neural processing. So, if chaos were coupled with quantum uncertainty in the brain, there is at least a possible means for indeterminacy to be significant enough to allow for a free decision.

Self-Forming Actions and Parallel Processing

In addition to genuine indeterminacy, we have seen that ultimate responsibility is also a necessary condition for freedom. It isn't enough for the future to be open to us if it is decided in a random or arbitrary fashion. Whatever outcome, a human being must be responsible for it if it is to be considered free. Kane points out here that for a man or woman to be responsible for a decision, it doesn't need to be directly based on a free choice-- it could have been the deterministic result of a previous free choice. In this way, only a small subset of our actions need actually be based on free choices in order for us to be considered free. This subset of actions, Kane refers to as "Self-Forming Actions" because they might have the effect of molding the type of person that one will end up being.

The uncertainty and inner tension we feel at such soul-searching moments of self-formation [could] be reflected in the indeterminacy of our neural processes themselves. [...] Consider a businesswoman who faces a conflict of this kind. She is on her way to an important meeting when she observes an assault taking place in an alley. An inner struggle arises between her conscience on the one hand (to stop and call for help for the assault victim) and her career ambitions on the other hand, which tell her she cannot miss this important business meeting. She has to make an effort of will to overcome the temptation to do the selfish thing and go on to the meeting.2

At such a moment, we might imagine that two related neural processes in the woman's brain are working simultaneously; one is causing the desire for her to continue on to her meeting, because she doesn't want to let her boss down, and the other is causing the desire for her to help the victim of the assault. Each process is causing "noise" for the other, thus creating indecisiveness. If she overcomes her temptation to hurry on, it will have been the result of her effort to do the moral thing. Since she will have had strong reasons for either outcome, her decision can hardly be said to be random or arbitrary.

[In such moments] the choices will be willed by the agents either way when they are made, and done for reasons either way-- reasons that the agents then and there endorse. But these are the conditions usually required to say that something is done "on purpose" rather than accidentally, capriciously, or merely by chance.3

Clearly such an action is under the control of the agent. Indeterminacy in her neural processing created a window in which she might make a free "self-forming" decision.


While I think Kane did a fantastic job explaining most of the issues surrounding the free will debate, I do not think I can fully endorse his own view of science and free will-- at least not yet. It isn't as if I think he is wrong. I think his view is very interesting and worth consideration. I am hesitant to accept it then for two reasons: first, I do not know enough about Chaos Theory and how it may manifest in the human brain to judge whether it really has the potential to magnify the effects of quantum indeterminacy in decision making. Second, and more importantly, I am worried that this doesn't solve the problem of why indeterminate actions are neither arbitrary nor random, but rather takes the question back a step. In the example of the businesswoman, while her actual decision may be considered voluntary or under her control-- since she had good reasons for both competing decisions-- the way in which one "neural process" actually overtakes the other seems to be open to the charge of randomness or arbitrariness. As I said previously, I am not by any means arguing against the theory, but simply saying it is not developed enough (or I do not understand it well enough) to endorse it.


1. Kane, 2005, pg. 133
2. Ibid. pg. 136
3. Ibid. pg. 138
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