Consider the case of a ten-year-old female epileptic patient. Neurosurgeon Itzhak Fried was performing brain surgery while she was awake (which is feasible because there are no pain receptors in the brain).14 Whenever he stimulated a particular spot on her neocortex, she would laugh. At first the surgical team thought that they might be triggering some sort of laugh reflex, but they quickly realized that they were triggering the actual perception of humor. They had apparently found a point in her neocortex—there is obviously more than one—that recognizes the perception of humor. She was not just laughing—she actually found the situation funny, even though nothing had actually changed in the situation other than their having stimulated this point in her neocortex. When they asked her why she was laughing, she did not reply along the lines of, “Oh, no particular reason,” or “You just stimulated my brain,” but would immediately confabulate a reason. She would point to something in the room and try to explain why it was funny. “You guys are just so funny standing there” was a typical comment.
We are apparently very eager to explain and rationalize our actions, even when we didn’t actually make the decisions that led to them. So just how responsible are we for our decisions? Consider these experiments by physiology professor Benjamin Libet (1916–2007) at the University of California at Davis. Libet had participants sit in front of a timer, EEG electrodes attached to their scalps. He instructed them to do simple tasks such as pushing a button or moving a finger. The participants were asked to note the time on the timer when they “first become aware of the wish or urge to act.” Tests indicated a margin of error of only 50 milliseconds on these assessments by the subjects. They also measured an average of about 200 milliseconds between the time when the subjects reported awareness of the urge to act and the actual act.15
The researchers also looked at the EEG signals coming from the subjects’ brains. Brain activity involved in initiating the action by the motor cortex (which is responsible for carrying out the action) actually occurred on average about 500 milliseconds prior to the performance of the task. That means that the motor cortex was preparing to carry out the task about a third of a second before the subject was even aware that she had made a decision to do so.
The implications of the Libet experiments have been hotly debated. Libet himself concluded that our awareness of decision making appears to be an illusion, that “consciousness is out of the loop.” Philosopher Daniel Dennett commented, “The action is originally precipitated in some part of the brain, and off fly the signals to muscles, pausing en route to tell you, the conscious agent, what is going on (but like all good officials letting you, the bumbling president, maintain the illusion that you started it all).”16 At the same time Dennett has questioned the timings recorded by the experiment, basically arguing that subjects may not really be aware of when they become aware of the decision to act. One might wonder: If the subject is unaware of when she is aware of making a decision, then who is? But the point is actually well taken—as I discussed earlier, what we are conscious of is far from clear.
Indian American neuroscientist Vilayanur Subramanian “Rama” Ramachandran (born in 1951) explains the situation a little differently. Given that we have on the order of 30 billion neurons in the neocortex, there is always a lot going on there, and we are consciously aware of very little of it. Decisions, big and little, are constantly being processed by the neocortex, and proposed solutions bubble up to our conscious awareness. Rather than free will, Ramachandran suggests we should talk about “free won’t”—that is, the power to reject solutions proposed by the nonconscious parts of our neocortex.
Consider the analogy to a military campaign. Army officials prepare a recommendation to the president. Prior to receiving the president’s approval, they perform preparatory work that will enable the decision to be carried out. At a particular moment, the proposed decision is presented to the president, who approves it, and the rest of the mission is then undertaken. Since the “brain” represented by this analogy involves the unconscious processes of the neocortex (that is, the officials under the president) as well as its conscious processes (the president), we would see neural activity as well as actual actions taking place prior to the official decision’s being made. We can always get into debates in a particular situation as to how much leeway the officials under the president actually gave him or her to accept or reject a recommendation, and certainly American presidents have done both. But it should not surprise us that mental activity, even in the motor cortex, would start before we were aware that there was a decision to be made.
What the Libet experiments do underscore is that there is a lot of activity in our brains underlying our decisions that is not conscious. We already knew that most of what goes in the neocortex is not conscious; it should not be surprising, therefore, that our actions and decisions stem from both unconscious and conscious activity. Is this distinction important? If our decisions arise from both, should it matter if we sort out the conscious parts from the unconscious? Is it not the case that both aspects represent our brain? Are we not ultimately responsible for everything that goes on in our brains? “Yes, I shot the victim, but I’m not responsible because I wasn’t paying attention” is probably a weak defense. Even though there are some narrow legal grounds on which a person may not be held responsible for his decisions, we are generally held accountable for all of the choices we make.
The observations and experiments I have cited above constitute thought experiments on the issue of free will, a subject that, like the topic of consciousness, has been debated since Plato. The term “free will” itself dates back to the thirteenth century, but what exactly does it mean?
The Merriam-Webster dictionary defines it as the “freedom of humans to make choices that are not determined by prior causes or by divine intervention.” You will notice that this definition is hopelessly circular: “Free will is freedom….” Setting aside the idea of divine intervention’s standing in opposition to free will, there is one useful element in this definition, which is the idea of a decision’s “not [being] determined by prior causes.” I’ll come back to that momentarily.
The Stanford Encyclopedia of Philosophy states that free will is the “capacity of rational agents to choose a course of action from among various alternatives.” By this definition, a simple computer is capable of free will, so it is less helpful than the dictionary definition.
Wikipedia is actually a bit better. It defines free will as “the ability of agents to make choices free from certain kinds of constraints…. The constraint of dominant concern has been…determinism.” Again, it uses the circular word “free” in defining free will, but it does articulate what has been regarded as the principal enemy of free wilclass="underline" determinism. In that respect the Merriam-Webster definition above is actually similar in its reference to decisions that “are not determined by prior causes.”
So what do we mean by determinism? If I put “2 + 2” into a calculator and it displays “4,” can I say that the calculator displayed its free will by deciding to display that “4”? No one would accept that as a demonstration of free will, because the “decision” was predetermined by the internal mechanisms of the calculator and the input. If I put in a more complex calculation, we still come to the same conclusion with regard to its lack of free will.