Free Will & Brain Science

Whether humans have conscious choice about their actions is an important question when discussing subjects such as morality and the soul. If God exists and has made us in His image, then we have a soul, are not merely body, and can make decisions of our own accord, without prior cause. If God does not exist, then all that exists are natural forces and humans are but complex biological machines that operate on natural forces. Surprisingly, I have found many atheists who in one breath maintain that everything that exists is reducible to matter and energy, then in the next breath hold that we have free will and can make moral choices. I sometimes find myself having to explain to atheists that if God does not exist, we are left with pure physical and chemical forces, and we do not have the free will to make moral choices; but if we do make moral choices, then physicalism is denied, and God exists. (For a detailed argument supporting human agency, start here).

Atheist philosophers who have thought this through are in agreement. In his book Free Will atheist writer Sam Harris denies that humans have free will or make free choices, and holds that all thoughts and decisions are caused by natural forces. As evidence, Harris provides the following:

The physiologist Benjamin Libet famously used EEG to show that activity in the brain’s motor cortex can be detected some 300 milliseconds before a person feels that he has decided to move. Another lab extended this work using functional magnetic resonance imaging (fMRI): Subjects were asked to press one of two buttons while watching a “clock” composed of a random sequence of letters appearing on a screen. They reported which letter was visible at the moment they decided to press one button or the other. The experimenters found two brain regions that contained information about which button subjects would press a full 7 to 10 seconds before the decision was consciously made. More recently, direct recordings from the cortex showed that the activity of merely 256 neurons was sufficient to predict with 80 percent accuracy a person’s decision to move 700 milliseconds before he became aware of it.

These findings are difficult to reconcile with the sense that we are the conscious authors of our actions. One fact now seems indisputable: Some moments before you are aware of what you will do next–a time in which you subjectively appear to have complete freedom to behave however you please–your brain has already determined what you will do. (p.8-9)

Harris goes on in the remainder of the book to explain the implications of this, telling us that we do not have free will, cannot make free moral choices, and all our actions are fully determined. Harris maintains free will is an illusion.

Harris spends a great percentage of the book asserting his position, but this point about neurons firing before we are aware of our thoughts is one of the few evidences he presents in the short book. Therefore this point is significant to his argument.

I will admit up front that I am not qualified to evaluate neuroscience, I do not claim expertise in this field, nor do I keep up with the literature. I cannot say whether or not Mr. Harris understands the field well and presents the best current research. Perhaps he does.  If someone more qualified than I tells me my reasoning is hair brained, then I will stand corrected. I do not claim to speak authoritatively about brain science.

However, I do know a bit about how systems operate, and the human neurological system is indeed a system. All control systems have some similar characteristics, and I see no reason to hold that the human brain and nerve system should be exempt from these fundamental principles. I will illustrate using a simple example. Let’s say Bob has a heating system in his home. It operates like this:

Bob: I feel cold.
Bob: I will turn on the heater.
(time goes by)
Bob: I feel hot.
Bob: I will turn off the heater.

This works for a while, until Bob gets tired of constantly switching the heater, and decides to install a thermostat. It has several components that operate like this:

T1: Thermometer indicates too cold.
 T2: Control circuit tells heater to start.
T3: Heater starts.
 T4: Thermometer indicates too hot.
 T5: Control circuit tells heater to stop.
 T6: Heater stops.

We can know some things about this system. We know that time passes between T1 and T2, between T2 and T3, etc. We also know that time passes within each of these steps; a heater does not instantly start, but takes a bit of time to go through the starting process. These time periods may be short, but no step happens instantaneously. Further, even afer the control tells the heater to start, the room will continue to cool for a while before the thermometer recognizes a rise in temperature. So if we were to graph the cycle, it might look like this:

Figure 1. Temperature rise with T2 and T5 events.

Note in this sequence that the temperature continues to decrease after T2, and continues to rise after T5. There is a lag between the event and the result. This is typical control circuit logic that could be true for any machine, continuous chemical process, or biological system. Even plants have a system to recognize stimuli and respond with hormones and changes in the plant.

The point is that all systems have a time lag between the steps in the process. All control systems have natural factors that result in time lags in the system. It would only make sense that the brain, as a biological control system, would also have a lag between the initiation of an action and the realization of the event. Just like our home heating system has a lag between the control system deciding to start heating and the recognition that heating has begun, our consciousness could very well be experiencing a lag between the initiation of our thoughts and the realization that we are thinking. This would be especially true for something as subjective as me realizing when I began thinking, or trying to determine the exact moment that someone else began thinking. I see no proof here that neurons firing a millisecond prior to human awareness would eradicate all human agency and conscious choice. The logic does not appear to follow. Merely recognizing a sequence of events does not allow us to draw conclusions about causation. Even though some neurons fire just prior to a person recognizing they are thinking, it does not follow that ‘your’ brain determines what ‘you’ will do, without ‘you’ being in control. It could be the person initiates the first neuron firing, then becomes aware of the event a fraction of a second later.

But we can take this even further. Imagine the following conversation:

Mary: Wow, your heater started all by itself. It must be alive, and started itself up all by itself. 
 Bob: No, that’s not it. I have a thermostat that controls it. The thermostat started the heater.
Mary: Oh, I see, you’re right. Now I realize that there is a material cause for the heater starting. Therefore the system must have come to exist on its own, without a designer or builder.

Such a conclusion would be absurd. Just because we have figured out a proximate cause, we cannot conclude that there is no ultimate cause. In fact, the more complex the system, the greater the need for a designer. Thomas Aquinas knew this 750 years ago, and Aristotle a thousand years before that.

We therefore hold that humans have free will, materialism is an insufficient explanation, and a non-material cause is required. This we call God.

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About humblesmith

Christian Apologist & Philosopher
This entry was posted in Apologetics, Atheism, Philosophy, Uncategorized. Bookmark the permalink.

2 Responses to Free Will & Brain Science

  1. I read Free Will a few months ago, and was very disappointed. Did Harris even try to deal with the question philosophically? William Lane Craig addressed the implications of Libet earlier this year, and there are some common points to yours. But your explicit reference to systems theory is a new insight to me. Good work.

  2. Great blog post. I spotted the same problem with this same argument in Alex Rosenberg’s book. He and Harris must be reading the same research. It just seems obvious that our conscious awareness of a decision has nothing to do with whether our mind freely decided to make the decision. That is just a complete non sequitur that you very nicely illustrated.

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