Do humans have free will? Can people themselves choose their actions? The existence of free will has profound consequences for psychiatry. We ascribe to our patients the ability to choose their next action, to change their outlook, to cast off the shackles of their past. When we judge an individual to lack this ability, we may deprive them of their liberty, in their “best interests.” What would it mean if no individual could choose what choice or action to take? For one, it would render irrelevant a large part of forensic psychiatry, as everyone would fit the criteria of being “unable to refrain from committing the act.” More broadly, it would re-conceptualise disorders which diminish the patient’s free will, such as OCD or addiction.

Twin films are films with the same or similar plots released at similar times by two different studios, often when production companies hear of a script and race to produce the big hit. Although the topic of free will is more like an ancient text than a flashy new Hollywood script, two neurobiologists released major books on the subject, fortuitously within two weeks of each other in October 2023. Here I will compare “Determined” by Robert Sapolsky (a Neuroendocrinology Professor at Stanford University) and “Free Agents” by Kevin Mitchell (an Associate Professor of Developmental Neurobiology at Trinity College Dublin).

Sapolsky argues that we are simply the product of all manner of antecedents. Starting from our current environment and physiology, and extending back to our evolution from simple organisms. Along the way, our culture, genetics, and upbringing exert their own influence. Sapolsky builds a solid biological determinist treatise making it difficult to claim any cell, or neurone, is acting of its own accord, free from influences. He then tackles three common theories used to argue against free will. Chaos Theory, Emergence, and Quantum Theory. For those not familiar with Sapolsky, he is renowned for making complex topics delightful and comprehensible. After years of scratching my head while attempting to understand Emergence, Quantum Theory, and Chaos Theory, “Determined” permitted me to grasp them on at least a basic level.

Sapolsky argues that Chaos Theory, though it makes events wildly unpredictable does not render events indeterminable, basically that though events cannot be predicted by us mere mortals, we can deduce with hindsight why they occurred. Emergence can render new properties to objects, but does not render newfound abilities to them; it can explain why a flock of birds moves as one but does not allow the birds to defy the laws of physics. His dismissal for the effects of Quantum Theory is less persuasive. His basic argument is that quantum effects at the subatomic scale even out at a macro level. Despite this, his primer on Quantum Theory is intuitive and enjoyable, and shows that it does not allow one to inject quasi-magic into a pet theory. For example, entanglement (that linked particles instantly affect each other’s state, regardless of distance) does not allow someone to interact with another across space or time, as proposed by “Quantum Psychoanalysis.”

As Sapolsky repeatedly says, the search for free will in the chain of what caused what reveals nothing but “turtles all the way down”. Once you start looking for what influenced one cell, you find that another cell influenced that influencer, and all the way down. For Sapolsky, there is no room for free will to be exercised in this chain.

Mitchell argues that evolution has provided organisms with the ability to choose what “matters to them.” He maintains that quantum indeterminacy, the fact that qualities of subatomic atoms are inherently unpredictable, gives humans their own “slack” in escaping from determinism (though this premise rests on one specific interpretation of quantum mechanics). It does so by creating “noise” within the nervous system’s biochemistry, a process which he believes is vital for complex biological beings to function. He further argues that evolution has equipped agents, and ultimately humans, with increasingly complex biological mechanisms. Through these mechanisms, humans can now “choose” to do what “matters” to them, aided by the randomness generated from the noise within their systems. Although these may seem like fuzzy, unscientific words, what “matters” to the agent, and why it “chooses” to do it are grounded in the its evolutionary and personal past. This choice can alter the agents physiology and biochemistry so that its path is no longer fully determined.

The grander claim presented by Sapolsky allows him the space to explore its consequences in the latter section of his book. He envisions a future in which the belief of a lack of free will is adopted. This is where his self-confessed “bleeding liberal heart” shines through, picturing a future that would reject our notion of meritocracy and cast away barbaric practices such as punishing people for their behaviour. He essentially argues that all people should be found Not Guilty by Reason of Insanity, with nobody ever having true “control” of their actions. They should be quarantined from society but not punished. This future would look back on society in 2023 in horror, in much the same way we do at society’s past treatment of epileptic and psychotic individuals. A rather ironic twist is that he seems to suggest a quasi-dystopian pre-selection of individuals to undergo this insulation, a form of poena sine culpa.

For the interested psychiatrist, the two books are complimentary. Both give rigorous defences of their position. “Determined” is an incredibly enjoyable and easy read, whereas “Free Agents” is, by comparison, drier and more challenging, but does give the impression of taking a more scientific approach. To draw on our twin movie analogy, Sapolsky’s accessible read might be the “blockbuster” and Mitchell’s denser work the “critics’ choice.” I would highly recommend to any psychiatrist to read both. They have made me more versed in a vast array of topics both interesting and relevant to my work, even if I am no clearer on whether I chose to read them or not.