In this book Robert Sapolsky argues that there is no free will, defined as a behavior independent of the sum of its biological past. ”Here’s the challenge to a free willer: Find me the neuron that started this process in this man’s brain, the neuron that had an action potential for no reason…”
When people claim that there are causeless causes of your behavior that they call “free will,” they have (a) failed to recognize or not learned about the determinism lurking beneath the surface and/or (b) erroneously concluded that the rarefied aspects of the universe that do work indeterministically can explain your character, morals, and behavior.
It began with Benjamin Libet, a neuroscientist at the University of California at San Francisco, in a 1983 study: Here’s a button. Push it whenever you want. Don’t think about it beforehand; look at this fancy clock that makes it easy to detect fractions of a second and tell us when you decided to push the button, that moment of conscious awareness when you freely made your decision. Meanwhile, we’ll be collecting EEG data from you and monitoring exactly when your finger starts moving, including a distinctive EEG signature called the readiness potential, when people prepared to move. But here’s the crazy thing: the readiness potential, the evidence that the brain had committed to pushing the button, occurred about three hundred milliseconds before people believed they had decided to push the button. That sense of freely choosing is just a post hoc illusion, a false sense of agency.
Sapolsky covers some of the common critiques of Libet’s experiments, including that the readiness potential isn’t 100% predictive of behavior, and concludes that “Free will, I believe, survives Libetianism. And yet I think that is irrelevant.” “Here’s why these Libetian debates, as well as a criminal justice system that cares only about whether someone’s actions are intentional, are irrelevant to thinking about free will. As first aired at the beginning of this chapter, that is because they don’t asks a question central to every page of this book: Where did that intent come from in the first place?” A central theme of this book is that while we’re free to do as we intend, we’re not free to intend what we intend.
Neuroplasticity relevant to free will-lessness. Developing post-traumatic stress disorder after trauma transforms the amygdala. Synapse number increases along with the extent of the circuitry by which the amygdala influences the rest of the brain. Suffer from major depression for decades and the hippocampus shrinks, disrupting learning and memory. For every step higher in one’s ACE score, there is roughly a 35 percent increase in the likelihood of adult antisocial behavior, including violence; poor frontocortical-dependent cognition; problems with impulse control; substance abuse; teen pregnancy and unsafe sex and other risky behaviors; and increased vulnerability to depression and anxiety disorders. Your genes and childhood will even regulate how easily your brain changes in response to adult experiences.
Cultural differences arising centuries, millennia, ago, influence behaviors from the most subtle and minuscule to dramatic. Pastoralist vulnerability to theft has generated “cultures of honor” with the following features: (a) extreme but temporary hospitality to the stranger passing through - after all, most pastoralists are wanderers themselves with their animals at some point; (b) adherence to strict codes of behavior, where norm violations are typically interpreted as insulting someone; (c) such insults demanding retributive violence. A cultural comparison between “tight” cultures (with numerous and strictly enforced norms of behavior) and “loose” ones shows that a history of lots of cultural crises, droughts, famines, and earthquakes, and high rates of infectious diseases is associated with tight cultures. Even if that history happened 500 years ago.
So you have certain biological attributes, but you can still choose what to do with it right? Someone with a history of alcoholism in their family can choose to stay away from environments that will make them drink right? Sapolsky argues that we have as little control over the “what we do with it” side of the equation as we do over the biological proclivities.
The PFC that inhibits you from doing something the habitual way when you’re supposed to be doing it in a novel manner. The dorsolateral PFC (dlPFC) is the rational decider in the frontal cortex. Inactivate the dlPFC, and subjects become more impulsive - they rate a lousy offer in an economic game as unfair but lack the self-control needed to hold out for a better reward. The other key subregion of the PFC is called the ventromedial PFC (vmPFC), which is how the PFC finds out what you’re feeling. People with vmPFC damage have trouble making decisions, because they’re not getting gut feelings about how they should decide. People with vmPFC damage don’t shift their behavior based on negative feedback. PFC function and self-regulation also go down the tubes if you’re terrified or in pain, or tired. Have a horribly stressed morning, and by noon, glucocorticoids will have changed gene expression in the dlPFC, making it less excitable and less able to couple to the amygdala and calm it down.
Adolescent social experience will alter how the PFC regulates social behavior in adults. How? Round up all the usual suspects. Lots of glucocorticoids, lots of stress (physical, psychological, social) during adolescence, and your PFC won’t be its best self in adulthood. There will be fewer synapses and less complex dendritic branching in the mPFC and orbitofrontal cortex, along with permanent changes in how PFC neurons respond to the excitatory neurotransmitter glutamate (due to persistent changes in the structure of one of the main glutamate receptors).
Childhood abuse produces an adult PFC that is smaller, thinner, and with less gray matter, altered PFC activity in response to emotional stimuli, altered levels of receptors for various neurotransmitters, weakened coupling between both the PFC and dopaminergic “reward” regions (predicting increased depression risk), and weakened coupling with the amygdala as well, predicting more of a tendency to respond to frustration with anger (“trait anger”).
Some takeaways: (a) grit, character, backbone, tenacity, strong moral compass, willing spirit winning out over weak flesh, are all produced by the PFC; (b) the PFC is made of biological stuff identical to the rest of your brain; (c) your current PFC is the outcome of all that uncontrollable biology interacting with all that uncontrollable environment.
Does free will live in chaos theory? Various thinkers find free will in chaoticism. Compatibilists and incompatibilists debate whether free will is possible in a deterministic world, but now you can skip the whole mess because chaoticism supposedly shows that the world isn’t deterministic. After all, chaos theory shows that small differences in starting conditions magnify unpredictably over time. Sapolsky argues that there is a critical mistake running through all of this: determinism and predictability are very different things. Even if chaoticism is unpredictable, it is still deterministic. The difference can be framed a lot of ways. One is that determinism allows you to explain why something happened, whereas predictability allows you to say what happens next.
Does free will live in emergent systems? Emergence is about reductive piles of bricks producing spectacular emergent states, ones that can be thoroughly unpredictable or that can be predicted based on properties that exist only at the emergent level. So these free-will believers accept that an individual neuron cannot defy the physical universe and have free will. But a bunch of them can; to quote List, “free will and its prerequisites are emergent, higher-level phenomena.” Sapolsky thinks not. Even if a system is emergent, that doesn’t mean it can choose to do whatever it wants; it is still made up of and constrained by its constituent parts.
Does free will live in quantum indeterminacy? The inability to know both location and momentum, the fact of superposition and things being in multiple places at once, the impossibility of knowing which slit an electron will pass through once a wave has collapsed into a particle - all introduce a fundamental indeterminism into the universe. Peter Tse, who considers the neurotransmitter glutamate, where the workings of one of its receptors requires popping a single atom of magnesium out of an ion channel that it blocks. In Tse’s view, the location of the magnesium can change in the absence of antecedent causes, because of indeterminate quantal randomness. And these effects bubble up further: “The brain has in fact evolved to amplify quantum domain randomness…up to a level of neural spike timing randomness” (my emphasis) - i.e., up to the level of individual neurons being indeterminate. And the consequences then ripple upward further into circuits of neurons and beyond.
It is perfectly plausible, maybe even inevitable, that there will be quantum effects on how things like ions interact with the likes of ion channels or receptors in the nervous system. However, there is no evidence that those sorts of quantum effects bubble up enough to alter behavior, and most experts think that it is actually impossible - quantum strangeness is not that strange, and quantum effects are washed away amid the decohering warm, wet noise of the brain as one scales up.
This is the bubbling-up problem in going from quantum indeterminacy at the subatomic level up to brains producing behavior - you’d need to have an unimaginably large number of such random events occurring at the same time, place, and direction. Instead, most experts conclude that the more likely scenario is that any given quantum event gets lost in the noise of a staggering number of other quantum events occurring at different times and directions.
Even if quantum indeterminacy did bubble all the way up to behavior, there is the fatal problem that all it would produce is randomness. Do you really want to claim that the free will for which you’d deserve punishment or reward is based on randomness?
Will a lack of belief in free will cause us to run amok? To test this, the experimental approach is simple - prime people to decrease their belief in free will, see if they now become jerks. Economist Katherine Vohs of the University of Minnesota show that free-will skeptics become more antisocial in their behaviors. In experiments, they are more likely to cheat on a test and to take more than their fair share of money from a common pot. They become less likely to help a stranger in need and more aggressive.
However, the bulk of studies have failed to replicate the basic finding that people become less ethical in their behavior when their free-will belief is weakened.
What about a natural experiment? Do atheists run amok? Like free will skeptics, atheists may feel less of a sense of responsibility for their actions because they don’t believe they’re being judged by god. Most people sure believe that, and antiatheist prejudice runs wide and deep. At first pass, the bulk of studies in this large literature support the notion that deciding that there is no god to monitor you makes for rottener people. As compared with religious people, atheists are less honest and trustworthy, are less charitable in both experimental settings and out in the real world, volunteer less of their time.
However, a large percentage of the relevant literature is based on “self-reporting” rather than empirical data, and it turns out that religious people are more concerned than atheists with maintaining a moral reputation, arising from the more common personality trait of being concerned about being socially desirable. This no doubt reflects the fact that theists are more likely than atheists to live their moral lives in the context of a cohesive social group. Additionally, once you actually observe what people do, rather than listen to what they say, there’s no difference between theists and atheists in rates of blood donations, amount of tipping, or compliance with “honor system” payments; ditto for a lack of difference in being altruistic, forgiving, or evincing gratitude. Furthermore, there’s no difference in being aggressive or vengeful in experimental settings where subjects can retaliate against a norm violation (for example, by administering what they believe to be a shock to someone).
Being in a stable social network seems to be really important. For example, the increased charitability and volunteering found in religious people is not a function of how often they pray but, instead, how often they attend their house of worship, and atheists who show the same degree of involvement in a close-knit community show the same degree of good-neighborliness (in a similar vein, controlling for involvement in a social community significantly lessens the difference in rates of depression among theists versus atheists).
Really crucial point: religious prosociality is mostly about religious people being nice to people like themselves. It’s mostly in-group. In economic games, for example, the enhanced honesty of religious subjects extends only to other players described to them as coreligionists, something made more extreme by religious primes. Sapolsky thinks that free-will believers will feel more of a moral imperative (versus an instrumental strategy) to help someone who is making an extra effort at something, while free-will skeptics will feel more of an imperative to understand the actions of someone very different from them.
We’ve changed before: We used to assign personal blame to many conditions that we now view more compassionately. For example, most people in the Westernized world have subtracted free will, responsibility, and blame out of their thinking about epilepsy. Similarly, our modern understanding of schizophrenia has done away with the concept of schizophrenogenic mothering. We now know that schizophrenia is a neurodevelopmental disorder with strong genetic components. We can make more positive change.
Our main takeaways:
- This book starts with the assumption that the universe (including our brains) is completely constrained by the laws of physics. If it is, then if you could reverse time, reversing all the chemical reactions and interactions of particles 2 seconds before you made a decision, and then allowed time to move forward again - all of the exact same chemical reactions and particle interactions would occur again, in exactly the same way, and you would make the exact same decision. If you reversed time like this a million times, you would make the same decision a million times.
- The example in (a) might not actually be true because quantum theory suggests that certain properties of particles are intrinsically probabilistic and not fully determined. It seems very unlikely that this randomness influences decisions, because this randomness is mostly canceled out. However, even if it did affect decisions, this doesn't actually help the idea of free will at all because now you just have differences in the decision outcome that were based on randomness. Free will depends on some idea of you existing separately from your brain - and able to exert an influence on the brain from somewhere else.
- Free will isn't a stable concept, and we've actually been chipping away at the idea for thousands of years. Now, for certain brain conditions, such as epilepsy or a tumor pushing on your amygdala or a very traumatic brain injury that destroys part of your brain or if someone sleep walks, we think that people who commit crimes that were caused by these conditions have little to no personal responsibility for their actions. The same reasoning is starting to apply for conditions like autism or schizophrenia, where the condition is based on a complex set of gene mutations and environmental interactions with those genes. The same may even apply to psychiatric conditions that are caused by early childhood abuse or trauma. Often, when we understand what biological, or sometimes, environmental factor strongly influenced the bad behavior, we label it as a pathology, and it gets removed from our conception of free will (e.g. that person didn't have free will to make that choice because their brain was "damaged"). There is no reason to think that this won't just continue to expand to include subtler causes, especially as we understand the interactions between those subtler causes (e.g. that person didn't have free will to choose not to steal that candy because their brain was "damaged" from all the genetic and environmental factors that led their brain to be the way it was).
TLDR: Free will is the biology of decision making we don’t understand yet. As we understand more about the brain, more and more things are excluded from the category of “free will.”
Thought questions:
- Sapolsky argues that genes have a decreased impact on things that develop later in life. For example, aspects of prefrontal cortex development are less under the control of genes and more under control of environment because it develops slowly and so late into development. This seems to contradict what we learned in Blueprint by Robert Plomin, which found that the heritability of traits (the variance in traits that can be attributable to genes) actually increases with age. Plomin argues that this is because certain characteristics in development can be pushed one way due to environmental interactions, but as we continue developing, our genes exert a compounding effect that move us back closer to the characteristic that the genes predict. However, in Blueprint, Plomin glossed over the importance of gene-environment interactions. Do you think that certain genes are programmed to be more affected by environment than other genes? How would this occur?
- Sapolsky arguing against retributive punishment seems to us like it would depend on the fact that the specter of punishment does not influence the decision making process of people. This may not be true. Decisions about actions seem qualitatively different from actions that are not decision-based (such as having your first seizure while driving a car). There is much more complexity in the combination of variables that cause the outcome of a decision. Clearly, humans are making decisions all the time, even if the outcome of those decisions are predetermined. In many examples, Sapolsky talks about ways in which society can exert its influence on the decision making of individuals. For instance, a society which offers lots of support and a strong safety net seems to lower stress and make the propensity for committing certain crimes or violence less likely. How is this different than a society upholding retributive punishment as a deterrent against bad behavior?
We felt like the main argument against retributive punishment is more around structuring society in a way that tries to minimize suffering, which we agree with. But we weren’t convinced that not believing in free will was a sufficient argument to get rid of punishment, without demonstrating that punishment actually doesn't deter bad behavior. What do you think?