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56 pages 1 hour read

Robert M. Sapolsky

Determined: A Science of Life without Free Will

Nonfiction | Book | Adult | Published in 2023

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Important Quotes

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“Let me state this most broadly, probably at this point too broadly for most readers: we are nothing more or less than the cumulative biological and environmental luck, over which we had no control, that has brought us to any moment.”


(Chapter 1, Page 4)

This line sums up the concept and implications of determinism as it relates to behavior: All human behavior is caused by preceding conditions rather than by free will. Sapolsky acknowledges the controversy in this statement and preemptively addresses skepticism. By including the phrasing “at this point,” Sapolsky suggests that he will be able to successfully convince skeptics to consider his views.

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“Collectively, what does this Libetian literature, starting with Libet, show? That we can have an illusory sense of agency, where our sense of freely, consciously choosing to act can be disconnected from reality; we can be manipulated as to when we first feel a sense of conscious control; most of all, this sense of agency comes after the brain has already committed to an action. Free will is a myth.”


(Chapter 2, Page 26)

Libet was one of the first researchers to find empirical evidence that could help disprove free will, and his research was modified to establish further support. Sapolsky cites many of these studies, and he incorporates their findings into this synopsis to help readers digest the large amount of technical information.

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“Where I am definitely trying to sound pejorative and worse is when this ahistorical view of judging people’s behavior is moralistic. Why would you ignore what came before the present in analyzing someone’s behavior? Because you don’t care why someone else turned out to be different from you.”


(Chapter 2, Page 42)

Sapolsky uses emotional language and hypophora to stress the idea that moral judgments should not be invoked when analyzing someone’s behavior. To morally judge someone shows a lack of empathy and tolerance for others’ differences. The use of hypophora—asking and immediately answering a question—is designed to encourage readers to self-reflect on their own views and to consider Sapolsky’s perspective.

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“Thus, the decisions you supposedly make freely in moments that test your character—generosity, empathy, honesty—are influenced by the levels of these hormones in your bloodstream and the levels and variants of their receptors in your brain.”


(Chapter 3, Page 55)

That hormones influence intent and decisions supports Sapolsky’s message that behavior should not be analyzed through a moral lens. Sapolsky uses repetition to emphasize this notion.

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“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. Oh, and also poorer health and earlier death.”


(Chapter 3, Page 66)

Adverse childhood experiences cause behavioral problems later in life, which provides a strong argument against free will. This concept refers to Dennett’s proposition that luck evens out over time by demonstrating that, in most instances, good and back luck compound.

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“Each moment flowing from all that came before. And whether it’s the smell of a room, what happened to you when you were a fetus, or what was up you’re your ancestors in the year 1500, all are things that you couldn’t control. A seamless stream of influences that, as said at the beginning, precludes being able to shoehorn in this thing called free will that is supposedly in the brain but not of it.”


(Chapter 3, Page 80)

The main argument Sapolsky makes against free will is that, when considering all the factors that impact behavior, there is no room for free will. The language used in the latter half of the final sentence uses a satirical tone to emphasize the point that the existence of free will is unlikely.

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“Your you-ness is made of nanochips, old vacuum tubes, ancient parchments with transcripts of Sunday-morning sermons, stalactites of your mother’s admonishing voice, streaks of brimstone, rivets made out of gumption. Whatever the real you is composed of, it sure ain’t squishy biological brain yuck.”


(Chapter 4, Page 93)

Sapolsky uses numerous literary devices in rapid succession to communicate the idea that many people struggle to accept the concept that humans are purely biological organisms. Hyperbole, metaphor, and imagery appear in the sarcastic examples of where “you-ness” stems from.

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“We all have thoughts—hateful, lustful, boastful, petulant—we’d be mortified if anyone knew. Be frontally disinhibited and you say and do exactly those things. When one of those diseases occurs in an eighty-year-old, it’s off to a neurologist. When it’s a fifty-year-old, it’s usually a psychiatrist. Or the police. As it turns out, a substantial percentage of people incarcerated for violent crime have a history of concussive head trauma to the PFC.”


(Chapter 4, Page 99)

This chain of information is intended to encourage readers to reflect on their moral beliefs. The inclusive language—“We all”—incorporates the reader into the text. By stating that everyone has thoughts they are ashamed of, and then giving increasingly taboo examples of disinhibited behavior, Sapolsky guides the reader to shift their perspective on perpetrators of violent crime.

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“I will admit that the previous three chapters have an emotional intensity for me. I am put into a detached, professorial, eggheady sort of rage by the idea that you can assess someone’s behavior outside the context of what brought them to that moment of intent, that their history doesn’t matter.”


(Chapter 5, Page 126)

Sapolsky accounts for his biting and sarcastic tones in Chapters 2 through 4 by acknowledging his emotional reaction to the concept of moral judgment. His frustration with the common practice of morally judging people when they cannot control their behaviors is the driving force behind the text.

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“In this view, ‘free will’ is what we call the biology that we don’t understand on a predictive level yet, and when we do understand it, it stops being free will. Not that it stops being mistaken for free will. It literally stops being. There is something wrong if an instance of free will exists only until there is a decrease in our ignorance.”


(Chapter 6, Page 150)

The discussion of chaoticism introduces the idea that the concept of free will is correlated with ignorance. This reflects the commonly noted tendency of humans to search for answers and fill in the gaps in the absence of logical explanations.

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“You can be out of your mind but not out of your brain; no matter how emergently cool, ant colonies are still made of ants that are constrained by whatever individual ants can or can’t do, and brains are still made of brain cells that function like brain cells.”


(Chapter 8, Page 197)

Sapolsky uses logos—logical rhetoric—to argue against the idea that elements in an emergently complex system are free to choose. He bluntly compares the limited behavior in ants to the limited capabilities of individual brain cells to emphasize the determinism that rules both.

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“Why the dread? To start, (a) the chapters’ subject rests on profoundly bizarre and counterintuitive science (b) that I barely understand and (c) that even the people who you’d think understand it admit that they don’t, but with a profound noncomprehension, compared to my piddly cluelessness, and (d) the topic exerts a gravitational pull upon crackpot ideas as surely as does a statue upon defecating pigeons, a pull that constitutes a ‘What are they talking about?’ strange attractor.”


(Chapter 9, Page 203)

Sapolsky openly admits that he struggles to understand the concept of quantum indeterminacy. This cues the reader to take the chapters on this topic with a grain of salt, as Sapolsky is not an expert in quantum science. He uses humor in the form of self-deprecation and metaphor to demonstrate that many people use quantum indeterminacy to support illogical and outlandish hypotheses.

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“I’m not gonna lie—I’m not a big fan of folks touting crap like this concerning people in pain.”


(Chapter 10, Page 215)

The tone shifts from formal to informal, signaling a brief deviation from the technical discussion to Sapolsky’s emotional response. He uses casual language and understatement to convey his anger without being overtly offensive. His goal is to discourage readers from using quantum indeterminacy to explain neurological phenomena.

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“Moreover, I know of no biology that explains how having to make a tough decision causes thermodynamic disequilibrium in the brain; how chaoticism can be ‘stirred up’ in synapses; how chaotic and nonchaotic determinism differ in their sensitivity to quantum indeterminacy occurring at a scale many, many orders of magnitude smaller; whether downward causality causing quantum randomness to fuel the consistency of one’s choices in life does so by changing which electrons entangle with each other, how much nonlocality of time and backward time ravel is occurring, or whether the spread of clouds of superpositioned possibilities can be expanded far enough so that, in principle, your olfactory cortex, rather than your motor cortex, sometimes makes you sign a check.”


(Chapter 10, Page 237)

Sapolsky delivers a quick succession of arguments made by researchers such as Tse and Kane, who support the idea that free will is created by people “messing with” quantum indeterminacy. The rapid accumulation of information reinforces that such arguments are illogical.

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“The most important message was that these are not all separate -ology fields producing behavior. They all merge into one—evolution produces genes marked by the epigenetics of early environment, which produce proteins that, facilitated by hormones in a particular context, work in the brain to produce you. A seamless continuum leaving no cracks between the disciplines into which to slip some free will.”


(Interlude, Page 240)

Sapolsky employs an interdisciplinary approach in his analysis of behavior and free will, considering the concepts of both nature and nurture and how they work together. Rather than relying on repetition, Sapolsky directly tells readers that this “seamless” interaction negates the possibility of free will and is the most important takeaway from the first half of the text.

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“A belief in free will is generally ingrained in us by the time we learn about the sins of gluttony from The Very Hungry Caterpillar.”


(Chapter 11, Page 250)

This line uses a humorous tone and two allusions—an indirect biblical reference and a direct reference to a children’s book—to establish that humans develop a strong sense of free will at a young age. Using varying tones and creative devices is intended to make Sapolsky’s intellectual conversations more engaging and entertaining.

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“The question now becomes how readily you come to associate Mexicans with rapists while undergoing Trumpian conditioning—how resistant or vulnerable are you to forming that automatic stereotype in your mind? As usual, it depends on what happened one second before hearing his statement, one minute before, and so on.”


(Chapter 12, Page 289)

Sapolsky offers a real-world example to connect conditioning to the purpose of his text, which is to inspire free will skepticism for the betterment of society. This example of hypophora encourages reflection on how individuals are socio-politically conditioned. Sapolsky implies that those who are more susceptible to such conditioning should not be morally judged.

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“We have done this before, where we grew to recognize the true causes of something and, in the process, shed hate and blame and desire for retribution. Time after time, in fact. And not only has society not collapsed, but it has gotten better.”


(Chapter 13, Page 301)

The text transitions into the final stage of its argument, which is how widespread skepticism of free will can benefit society. Sapolsky introduces the concept that increased knowledge results in more tolerance and better social conditions, with the intent to inspire hope for a better future.

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“We have been able to subtract blame and the myth of free will out of the entire subject and, nonetheless, have found minimally constraining ways of protecting people who suffer—directly or secondarily—from this terrible disease.”


(Chapter 13, Page 312)

Sapolsky introduces the concept that people should be minimally constrained for the benefit of society rather than for retributive purposes. This is a core principle in the text, as many people are concerned that free will skepticism would lead to the allowance of antisocial behaviors. Sapolsky addresses this fear in his argument that people can be held accountable without being punished or judged.

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“Prisons are criminogenic, a training ground for revolving-door recidivism. Implicit bias makes a mockery of the notion of objective judges and juries. The system offers all the justice money can buy.”


(Chapter 14, Page 343)

Sapolsky scornfully targets the criminal justice system, which contains high levels of recidivism, implicit bias, and financial corruption. The final line of this passage contains a sarcastic allusion to the idea that outcomes in the justice system are highly dependent on an individual’s financial status. The issues he identifies in his declarative statements are well documented, and he does not directly supply evidence to support his claims.

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“Suppose trials were abolished, replaced by mere investigation to figure out who actually carried out some act, and with what state of mind. No prisons, no prisoners. No responsibility in a moral sense, no blame or retribution.”


(Chapter 15, Page 347)

Sapolsky’s proposed justice system reform removes blame and punishment. The text carries a two-part purpose—first, to argue that free will is unlikely and, second, to demonstrate how the world could improve if people accepted this argument. Justice system reform becomes the primary example of how Dismantling the Concept of Free Will could benefit humanity.

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“Why don’t I hate him? Because he has a soul, whether it is soiled or not, and God forgives him. Because he is not smart enough to know that he’s been used and manipulated. Because, starting from childhood, he became embittered from loneliness, with a desperate need to be accepted and belong, and I am willing to call him by his first name and acknowledge that to him.”


(Chapter 15, Page 381)

There are several cases of survivors extending forgiveness to those who have committed violent crimes. While Sapolsky includes an array of examples, his underlying stance is that removing free will and moral judgment results in increased empathy.

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“There is nothing but an empty, indifferent universe in which, occasionally, atoms come together temporarily to form things we each call Me.”


(Chapter 15, Page 386)

This statement addresses the common opinion that life without free will is discouraging and meaningless. Sapolsky goes on to demonstrate that free will skepticism does not necessarily lead to despondence. He uses this structure—of introducing a conflicting argument and then counterarguing against it—throughout the text to efficiently address criticism while developing his position.

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“After all, most Americans have been educated to believe in free will and have reflected on how this produces responsibility for our actions. And most have also been taught to believe in a moralizing god, guaranteeing that your actions have consequences. And yet our rates of violence are unmatched in the West. We’re doing plenty of running amok as it is.”


(Chapter 15, Page 390)

Many hypothesize that the widespread denial of free will would lead to immoral and antisocial behaviors; Sapolsky counters this criticism by demonstrating that belief in free will does not guarantee moral behavior. His claim is an example of logos, or a logical argument, and it encourages reflection on the real-world relationship between free will and morality.

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“Having a neuropsychiatric disorder, having been born into a poor family, having the wrong face or skin color, having the wrong ovaries, loving the wrong gender. Not being smart enough, beautiful enough, successful enough, extroverted enough, lovable enough. Hatred, loathing, disappointment, the have-nots persuaded to believe that they deserve to be where they are because of the blemish on their face or their brain. All wrapped in the lie of a just world.”


(Chapter 15, Page 401)

Sapolsky uses a scornful tone to portray the idea that morally judging people for their attributes and behaviors is unjust. His primary goal in the text is to demonstrate the adverse consequences of attributing various traits and behaviors to free will. Here, he argues that, contrary to popular belief, the concept of free will has detrimental impacts at both the individual and societal levels. Implicit in this passage is his underlying message that such issues could be resolved through widespread skepticism of free will.

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