The Free Will: Determinism Debate in Contemporary Science and Society (Or: Why Are You Reading This Article?).

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Learn more: PMC Disclaimer | PMC Copyright Notice Perspect Behav Sci . 2025 Apr 17;48(2):475–497. doi: 10.1007/s40614-025-00447-3 Search in PMC Search in PubMed View in NLM Catalog Add to search The Free Will: Determinism Debate in Contemporary Science and Society (Or: Why Are You Reading This Article?) Reviewed by: Richard F Rakos Richard F Rakos 1 Cleveland State University, Cleveland, Ohio USA Find articles by Richard F Rakos 1, ✉ , Ruth Anne Rehfeldt Ruth Anne Rehfeldt 2 The Chicago School, Illinois, USA 3 Emergent Learning Centers, Illinois, USA Find articles by Ruth Anne Rehfeldt 2, 3 , Peter R Killeen Peter R Killeen 4 Arizona State University, Arizona, USA Find articles by Peter R Killeen 4 Author information Article notes Copyright and License information 1 Cleveland State University, Cleveland, Ohio USA 2 The Chicago School, Illinois, USA 3 Emergent Learning Centers, Illinois, USA 4 Arizona State University, Arizona, USA ✉ Corresponding author. Accepted 2025 Mar 18; Collection date 2025 Jun. © Association for Behavior Analysis International 2025 PMC Copyright notice PMCID: PMC12162392 Abstract The free will–determinism discussion is centuries old, with numerous stances taken by philosophers and scientists alike. The debate has clear implications for interpreting causal relations in scientific systems and predicting and influencing the behavior of living organisms, particularly humans. Advances in quantum physics and neuroscience have recently revitalized the debate over free will versus determinism, as depicted in recent books by Robert Sapolsky and Kevin Mitchell. In this article we review and critique Determined: A Science of Life Without Free Will (Sapolsky, 2023 ) and Free Agents: How Evolution Gave Us Free Will (Mitchell, 2023 ), which differ in their conclusions regarding how contemporary research findings in genetics, neuroscience, and quantum mechanics support or countervail the notion that people possess free will. Drawing on Killeen et al. ( 2024 ) recent analysis of agency, we attempt to reconcile the authors’ perspectives on the premise that the laws of physics, including quantum mechanics, imply hard determinism in terms of past events but can offer only broad, global predictions about a person’s future behavioral outcomes, because people entertain a range of considerations while deciding between available response options.. We suggest probabilistic determinism as a conceptualization of agency that accommodates this past–future distinction in determinism. We invite readers to consider that although behavior is determined, people nonetheless have opportunities to make choices and exercise autonomy. Keywords: Free will determinism, Agency, Libertarianism, Hard determinism, Compatibilism The free will–determinism debate is a resonant one, echoing through millennia from ancient Greece to today (Fischer et al., 2024 ). The ancient Greeks were long concerned with finding order and logic in the universe, but also contemplated the relationship between human virtue, morality, and causes of behavior. Epicureans were the first to propose the notion of randomness in the movement of atoms as a basis for free will (Long, 1977 ; Stanford Encyclopedia of Philosophy, 2024 ). But, of course, the lack of scientific proof of free will ensured that the debate endured; as noted by Rumi, the 13 th -century Persian poet and mystic, “There is a disputation that will continue till mankind is raised from the dead, between the necessitarians [determinists] and the partisans of free will” (Fischer et al., 2024 , p. 1). This historically unresolvable, deeply human controversy spawned three philosophical positions that have come to dominate the dialogue on free will, determinism, and their relationship to each other: libertarianism, hard determinism, and compatibilism, with the last sometimes called “soft determinism” (Fischer et al., 2024 ; Sapolsky, 2023 ). In recent studies, revisionism has been advanced as a fourth viewpoint (Fischer et al., 2024 ). Libertarians and hard determinists are incompatibilists, die-hard opposites, whereas the other two perspectives argue that free will can exist in a deterministic universe. Much of the contemporary research on this issue has focused on the extent to which a belief in free will, regardless of the reality of free will, may be a cultural (Mitchell, 2023 ) or biological (Rakos, 2004 ) adaptation that has profound societal benefits. 1 The different positions–each with several varieties—have important implications beyond a philosopher’s dissertation in how deviant, harmful, illegal, and antisocial behaviors are understood, and more important, how they are consequated by other individuals and by societal and cultural agencies, institutions, and the control systems of education, criminal justice, and politics. The debate has been energized by scientific advances in quantum physics, emergent complexity, and chaos theory that clearly demonstrate the unpredictability of a range of important natural phenomena. Is the thesis of determinacy viable in such an unpredictable world? Or do quantum and chaotic phenomena in some way support purposeful free agency? Do the underlying scientific principles and theories—and, of course, the data they generate—support one position more than others in the free will–determinism debate? This moves our discussion from philosophy to science, where two prominent neuroscientists recently engaged the debate in terms of evolution, biology, quantum mechanics, emergent complexity, chaos theory, the social sciences, and more—and come to opposite conclusions: Sapolsky ( 2023 ), a Stanford University professor of biology, neurology, neurological sciences, and neurosurgery, is a hard determinist who rejects free will; Mitchell ( 2023 ), an associate professor of genetics and neuroscience at Trinity College Dublin, is a compatibilist who embraces it. It will be helpful to first frame this scientific debate within its philosophical parameters. Therefore, the next section will offer a brief overview of the four major philosophical perspectives. The two sections that follow this tutorial will summarize Mitchell’s and then Sapolsky’s scientific analyses and conclusions. Finally, we will compare, contrast, and perhaps integrate these two diametrically opposed positions to help behavior analysts achieve a better appreciation of the competing assertions, contentions, and implications, along with a renewed, pragmatic stance on the determinism-free will debate today. A Thumbnail Summary of the Philosophical Debate Libertarianism, according to Kane in Fischer et al. ( 2024 ), promotes a scientifically valid “freedom of will” that “is not compatible with determinism” and has “the power to be the ultimate source and sustainer to some degree of one’s own ends and purposes” (p. 7). Further, our wills—“our characters, motives, and purposes”—are “formed or shaped” by our past experiences in choice situations where the actor “could have done otherwise;” these “self-forming actions” allow “acting of ‘our own free will’ by virtue of the fact that we formed it by other choices or actions in the past” and hence allow moral responsibility to be ascribed to the actor (Fischer et al., 2024 , pp. 7–8, emphasis in original). In other words, libertarians believe in a rational agent in which “not every event has causal antecedents that render it inevitable” (Fischer et al., 2024 , p. 93). 2 Hard determinists, in contrast, see causal events that lead to “inevitable” outcomes as universal; “because causal determinism is true, we cannot have the sort of free will required for moral responsibility” (Pereboom in Fischer et al., 2024 , p. 95). This is the position advocated by Sapolsky ( 2023 ), based on his focus on biological reductionism, as well as by Skinner ( 1971 , 1974 ), who grounds it in his positivist ideology. 3 Compatibilists like Fischer believe “that both some central notion of freedom and genuine, robust moral responsibility are compatible with causal determinism” (Fischer et al., 2024 , p. 51), which allows one to maintain the sense that more than one response option genuinely exists in a situation, even if causal determinism is true . In this tradition, Mitchell ( 2023 ) offers a sophisticated compatibilist argument that true free will emerges through the “top–down causation” (thoughts engaging muscles causing movement; p. 164) via the “causal slack” (error variance in deterministic systems that can be exploited by top–down causation) that is afforded by scientific findings in physics and neuroscience. Finally, revisionists focus on “the cognitive and social function of free will” (Vargas, quoted in Fischer et al., 2024 , p. 137) rather than a core concept or attribute of it: “free will is the situational ability to suitably recognize and appropriately respond to relevant normative considerations” (p. 151). In other words, this behavior-analytic-friendly conceptualization views free will as a social skill sensitively attuned to the contextual nuances that are important for effective behavior in complex communities. Revisionists contend that the three traditional approaches “permit a decoupling of philosophical interests from the everyday, on-the-ground facts of our practical lives” whereas in this “framing, the stakes of the debate are not some stipulative notion or armchair definition, but instead the comparatively concrete question of whether we have the kind of agency or power that grounds everyday responsibility practices and their apparent authority for us” (p. 216), i.e., the popular understanding of free will and its relationship to moral responsibility. Vargas’s model is similar to Sheldon’s ( 2024 ) recent effort at grappling with the concept; he conceptualizes free will as “the capacity to ask oneself what to do, get possible answers, then make and enact a choice” (p. 930) when autonomy (lack of constraints) and agency (the ability to generate intentions and enact behavior) are present, among several other factors. 4 Thus, revisionists join rational libertarians and compatibilists in reinforcing the notion that free will legitimates the ascription of blame and credit to actions. Only hard determinists reject imputing the moral responsibility that justifies punishment, preferring instead to utilize the idea of contingent accountability that promotes rehabilitation (Fischer et al., 2024 ; Sapolsky, 2023 ; Skinner, 1971 ). As we will see, Sapolsky devotes the second half of his book to reframing the notion of social and community responsibility without resorting to traditional societal concepts such as morality, blame, and judgment that are inherent in the belief in free will, whereas Mitchell ( 2023 ) argues that humans’ possession of meaningful free will leaves the traditional idea of moral responsibility intact. Mitchell’s Affirmation of Free Will and Rejection of Hard Determinism Free Agents: How Evolution Gave Us Free Will by Kevin J. Mitchell ( 2023 ) is a tantalizing exploration of how organisms evolved to exercise autonomy over their environments, make decisions about their course of action, and creatively problem-solve—what might in traditional philosophical debates be referred to as “having free will.” Mitchell’s career has focused upon the genetic basis for both the structure and function of the central nervous system; in particular, how the neocortex evolved to become the elegant structure capable of the many specialized functions that it has today. Over the course of the book Mitchell explains, in often great detail, how neurophysiological processes have evolved at multiple levels to grant living organisms a capacity for free will. Contrary to what one might expect, Mitchell’s stance on free will is not that of a dualist or mentalist whom behaviorists typically deride. In fact, one could argue that he is not a mentalist at all. Mitchell’s entire premise is based on the fact that the determinism of yesteryear, widely taught in undergraduate philosophy and psychology courses, is now an antiquated if not naïve position, due primarily to the replacement of the assumptions of classical, Newtonian physics with that of more contemporary quantum mechanics. Let us first provide a brief synopsis of some of the most basic tenets of contemporary physics, because this is the foundation upon which Mitchell’s stance can be best understood and the basis for which an open-minded position on determinism might be adopted. The system of determinism that characterized Western scientific thought was inspired by classical physics, formulated around the notion that every event that occurs in nature is preceded by some external cause that science can identify, limited only by its tools of experimentation and measurement. The underlying assumption is that scientists should be able to predict and explain every phenomenon that occurs in nature, particularly as its measurement techniques become more refined. Advances in quantum physics have shown this to be an impossible and unrealistic expectation for the way nature works (Prigogine & Stengers, 2018 ). Advances in quantum physics in recent decades have brought about a new understanding of causal relations in nature. It is now known that quantum particles behave differently than do massive particles. Early in the quantum revolution it was thought that one could never know the position and velocity of a particle simultaneously because measuring one disrupted the other—an epistemic limitation. It is now understood that the location of particles can never be completely ascertained due to their wave-like nature—an ontological limitation. Quantum particles behave like waves, meaning they can spread out, disperse, and interact with each other, and can be in multiple places at one time (Prigogine & Stengers, 2018 ). This notion is captured by the Heisenberg Uncertainty Principle, which stipulates that it is intrinsically impossible to determine with any certainty both the position and velocity of a particle due to the wave-like nature of particles comprising the physical world. This suggests that scientists can never make perfect predictions about any event in nature, and causal relations cannot be exactly determined -- and that improved measurement techniques can never change that. Critical to understand Mitchell’s position is the second law of thermodynamics, which states that systems have a natural tendency to move towards disorder unless energy is added that maintains order. Mitchell notes that living systems left to their own devices will become disorganized—atoms, as Mitchell explains, tend to get mixed up and randomly disperse when not constrained in a solid; they jiggle, bump and move into new arrangements that, much like tossing a deck of cards to the ground, are unpredictable—except for the eventual inevitable result of mortality and decomposition. For organisms to stay alive, they must keep their systems organized, which requires energy. The second law of thermodynamics gave rise to the concept of entropy, whose Greek etymology means “evolution” (Prigogine & Stengers, 2018 ), although “devolution” might be more appropriate. According to the second law, entropy—the disorder in a closed system—cannot decrease without the addition of external energy. The yolk cannot grow into a chicken without the energy provided by the albumin. Systems move between points of equilibrium, disequilibrium, and back, with energy utilized so that new organization or order can be achieved, over and over and over again. Because of the wave-like nature of particles, there are near-infinite possibilities for how a system reorganizes. In the end, in keeping themselves organized (viz. at low entropy), organisms take in energy and in doing so contribute to entropy of the world around them, to the “relentless disorder of the universe as a whole” (Mitchell, 2023 , p. 30). Mitchell ( 2023 ) challenges readers to consider several overarching questions at the outset of the book. They are: (1) How do living organisms come to make choices and autonomously control their own outcomes; (2) Does “true” agency exist, or might there be shades thereof?; and (3) at the end of the day, Is it “all just physics” (p. 12)? Mitchell ( 2023 ) is not exactly forthcoming in answering the last question, but it is indeed physics at the end of day—if quantum mechanics can provide the conceptual foundation by which choice, creativity, variability, and autonomy can arise, based on the laws of the physical world. This is our interpretation of Mitchell’s ( 2023 ) position. To this point Mitchell asserts that the question, “ do we have free will? ” is the wrong question to be asking, because it suggests that free will is a thing, entity, structure, or mechanism—it reifies it. Further, the speculation, “ if we have free will, how much do we have? ,” is unanswerable, because neither scientists nor philosophers could ever provide evidence of behavior detached entirely from a preceding cause. A far more logical question, Mitchell suggests, is “ what kind of thing are you? ” (p. 16). To this, he replies, we are living organisms that have the ability to self-organize, an evolved capacity to seek and find new order. It is this tendency for self-organization that Mitchell refers to as free will. Mitchell ascribes autonomy to what he describes as organisms’ means of generating an energy gradient. He contends that organisms have an ability to self-organize—to reduce their internal entropy—and to initiate their own exploration of new configurations or structures. He tells the story of single-celled organisms that did exactly this to keep their internal dynamics going. Movement or action, he affirms, was a “new trick” (Mitchell, 2023 , p. 19); because of the capacity for self-organization, organisms could float, swim, or crawl toward or away from predators, free to explore and take chances in the world around them, and the possibilities for how they did so were limitless. There were consequences of doing so, however, that were sometimes favorable and other times unfavorable for the survival of the organism. Each new form of movement was a variation; those variations that benefited the organism were selected for and retained through evolutionary processes and became wired into the biochemical circuitry of even very simple organisms. Organisms needed a way to sense where they were going, and next to evolve was an ability to interpret signals from the environment to guide their self-organization. Information, Mitchell notes, became a valuable commodity and mechanisms evolved so that organisms could gather it from the environment. New structures were formed and new variations were selected that were most advantageous for propagation of the species. Living organisms today therefore have an evolved ability to interpret and integrate information from the environment and use it to guide their behavior. Mitchell delineates how this process plays out at multiple levels, beginning at the level of the body’s cells and scaling up to the structure and function of the neocortex. Just as there was a degree of randomness or chance in how a living organism’s systems and structures organized and reorganized over time under the constraints of thermodynamic equilibrium, it follows that the selection of genes that permitted for self-organization was based on random variation. Neuroanatomical structures made it possible for organisms to receive information from the environment and adjust their responses in more and more sophisticated ways. Increasingly abstract concepts could be extracted from the environment, Mitchell explains, with evolution favoring organisms that were capable of associating semantic meaning to stimuli (Ginsburg & Jablonka, 2010 ). Evolution thus selected systems that could direct the dynamics of their composite parts, as mediated by hard-wired neural pathways (Mitchell, 2023 ). It is important to note that as organisms learned from their experiences with the environment, their structural features changed, they interacted with their environment differently, and environmental niches changed as a result. Mitchell’s narrative is saturated with detail on the intricate arrangement of cognitive apparatus. However, he does not ascribe special causal status to the cognitive equipment of organisms. This, among other aspects of his stance, make his position entirely palatable for behavior analysts for at least four reasons (bearing in mind that he discarded the question of “do we have free will?” at the beginning of his book). First, the mechanisms of selection articulated by Skinner ( 1984a , b ) are the engines by which new variations in structure and function are selected and retained, both phylogenically and ontogenically. Skinner ( 1984a , b ) was long a proponent that the principles of evolution could likewise explain the selection of behavior and cultural practices as well as genes, and Mitchell’s explanatory scheme is not unlike that of Skinner’s. In addition, it is further acknowledged by evolutionary scientists today that evolution is random—which variations are selected and retained is to some degree unpredictable. Gould ( 1989 ) recognized this in his conceptualization of punctuated equilibrium, which suggests that evolution proceeds through long periods of stability interrupted by short, rapid bursts of change, often caused by random or unpredictable environmental events. Gould ( 1989 ) also contended that seemingly small chance factors could have profound influence on the development of life, leading to outcomes that are not predetermined or inevitable; that if we were (able) to “replay the tape” of life’s evolution on earth, we are unlikely to arrive at a world like the one we know (Blount et al., 2018 ). Mitchell would agree, and states that evolution is anything but a series of “frozen accidents” (p. 101). Second, Mitchell characterizes the interaction between organisms and the environment as loops of causation, in which each produces change in the other, and so on. The behavior of organisms is thus not uncorrelated with or free from environmental influence. This in fact is the very basis for the definition of operant behavior, which is based on the notion that organisms operate on their environment just as environments influence organisms (Catania, 2013 ). Third, behavior analysts have long recognized that creativity or variability in behavior can be selected by contingencies of reinforcement as an operant class; further, that all behavior can be considered choice behavior is seldom any longer debated (Herrnstein, 1970 ; Williams, 1994 ). Finally, Mitchell’s ( 2023 ) resounding message is one that has already been acknowledged by behavior analysts and neatly summarized in Slife et al.’s ( 1999 ) taxonomy of determinism. One such variation in that taxonomy, metaphysical probabilism, has as its basis developments in contemporary physics. This perspective holds that the instrumentation involved in measurement not only limits the scientist’s ability to make accurate predictions, but the very act of measurement itself co-determines the behavior of that which is being measured. In other words, limitations in measurement constrain our ambitions of prediction and control. Moreover, the metaphysical probabilists would argue that the processes of nature itself behave in ways that physicists would characterize as nonlinear and often even chaotic: Some relations between variables will always be uncertain and unknowable. Further, although knowledge may increase as a field’s measurement techniques and equipment become more sophisticated, precision in experimentation is ultimately constrained by the nature of reality itself (Slife et al., 1999 ). This variety of determinism resonates well with the representation of determinism embraced by Skinner in the formulation of radical behaviorism (e.g., Skinner, 1984a , b ): there is a good reason why Skinner chose probability of response as the primary datum for our field—it was known from the beginning that only general patterns of behavior could be predicted. In advocating for the integration of fundamental principles from the field of physics into behavior analysis, Marr ( 1982 ) noted that random variations in behavior are revealed in even the most highly controlled laboratory conditions, supporting the notion that only aggregate, molar, or probabilistic estimates of behavior can ever be obtained in principle. Marr ( 1982 ) indicates that this realization was liberating for physicists and should be for behavior scientists as well. Mitchell ( 2023 ) would agree with Marr ( 1982 ): that nothing can be predicted with certainty need not be distressing. 5 For this means that there perpetually exists a window of opportunity for new variations and permutations in behavior—exactly what Skinner proposed in articulating the role of evolutionary mechanisms in the variation, selection, and retention of behavior over the course of an organism’s lifetime (Skinner, 1984a , b ). Which precise variations will be selected cannot be predicted with certainty. The possibilities are endless. In addition, according to Mitchell ( 2023 ), self-organization is exactly what makes organisms unique, special, and diverse from one another—what Mitchell refers to as becoming a self. Many readers will find this to be an optimistic view of human nature and of the potential power of behavior science. Sapolsky’s Affirmation of Hard Determinism and Rejection of Free Will Robert Sapolsky’s ( 2023 ) book Determined: A Science of Life without Free Will provides an analysis that arrives at the opposite conclusion to Mitchell’s ( 2023 ) proposal, also through a neuroscientific examination of the phenomena. Sapolsky is interested in answering one key question: Where does the intent to act come from? Whereas Mitchell begins his discourse with one-cell life forms and works forward in time to encompass increasing behavioral complexity, Sapolsky commences with the current response and works his way back through time to identify the proximate and distal causative factors that produce the intent to act. He begins the instant before the response is emitted, with Libet and associates’ (Libet et al., 1983 ; Libet, 1985 , 1999 ) classic experiments that found an electrical readiness potential formed 200–300 ms before self-reported awareness of a conscious intent to push a button or make some other discrete arbitrary response. He then goes back in time from the response by seconds, then minutes, days, weeks, and years before, and then back to adolescence, childhood, the womb, and, finally, even further back to genetic constitution, ancestral influences, and evolution. Sapolsky’s ( 2023 ) thesis is disarmingly simple yet philosophically and pragmatically profound: No factor exists without an earlier set of factors producing it. He uses the metaphor from a James ( 1890 / 1983 ) anecdote of being confronted by a woman in his audience who averred that the earth rested on a turtle. When asked what that turtle rested on, she asserted that “it’s turtles all the way down” (p. 1)—the world is on the back of a giant turtle that is standing of the back on another, lower turtle, which is on the back of another giant turtle, ad infinitum, as there is no bottom turtle that can simply float in air. Sapolsky borrowed the metaphor, flatly “reject[s] free will almost entirely on biological grounds” (p. 6) and argues that it is determinism all the way down. He acknowledges that the farther back in time the factor, the more general its influence, that remote factors are discounted more than proximate ones, and that factors interact with each other and with the products of previous interactions. Nevertheless, his bottom line take-away message might be summarized as “you can do what you want, but you can’t choose to want what you want.” Sapolsky ( 2023 ) insists that one must define free will as libertarian: “In order to prove there is free will, you have to show that some behavior just happened out of thin air in the sense of considering all these biological precursors” (p. 83). Compatibilists, of course, strenuously contend this is an unattainable, ridiculous criterion, but Sapolsky argues that “(i)t is anything but an absurdly high bar or straw man to say that free will can exist only if neurons’ actions are completely uninfluenced by all the uncontrollable factors that came before. 6 It’s the only requirement that can be, because all that came before, with its varying flavors of uncontrollable luck, is what came to constitute you. This is how you became you” (pp. 83–84). In other words, you are who you should be given your genes, your experiences, and the interactions among your genes and experiences. One might, of course, question what gives Sapolsky the authority to put the burden of proof on libertarians, who in response might say “In order to prove that all behavior is determined, you have to demonstrate the determinants of all behavior.” Sapolsky ( 2023 ) confronts three contemporary scientific threats to this biological determinism—quantum physics, chaos theory, and emergent complexity—and he finds them unpersuasive. Libertarians and compatibilists alike find philosophical and scientific comfort in the indeterminacy at the heart of quantum physics. Sapolsky offers neurobiological reasons why the indeterminacy that characterizes the subatomic level of analysis fails to hold in the macro world of classical physics. He discusses, for example, the theory that consciousness and free will emerge from the tight packaging of the microtubules that structure neurons, and transport “building blocks” within their axons and dendrites; the microtubules are hypothesized to be in perfect arrangement for quantum entanglement effects, where the properties such as direction of spin of two particles (e.g., electrons) are linked and exactly correlated. This is what Sapolsky calls “bubbling up,” and others label as “percolating up” (Pereboom, in Fischer et al., 2024 ), of subatomic indeterminacies to the macro, neural level. Sapolsky challenges this on sheer numbers. He notes that “the indeterminacy that releases magnesium from a single glutamate receptor doesn’t enhance excitation across a synapse all that much” (p. 220) and many synaptic excitations are needed to trigger an action potential. He does the math: 200 glutamate receptors per dendrite, 10,000–50,000 synapses per neuron, about 10,000,000 neurons in the hippocampus, his exemplar brain region. Even if quantum indeterminacy perturbs a single glutamate receptor, and each quantum event is random, “how likely is it that quantum events like these just happen to occur at the same time in the same direction (increasing or decreasing receptor activation) in enough of those 20–100 trillion receptors to produce an actual neurobiological event that has no deterministic cause?” (p. 220). In effect, Sapolsky argues that the quantum event is lost in the tumult of enormous numbers of competing quantum events at different times and directions. The results of the huge number of random quantum events occurring in any neurobiological action are predictable at the macro level in the same way that casino profits are predictable, despite being a function of millions of random events. This is consistent with Skinner’s philosophy (e.g., 1971 , 1974 ) and, most important, resonates with the matching law’s quantification of the probability of choice behaviors under concurrent schedules of reinforcement: because an organism will allocate its available response options to maximize the reinforcement available under a concurrent schedule, the probability of each potential response being emitted is predictable—though it is not possible to predict exactly which response option will be emitted in any particular trial (Herrnstein, 1961 ). Does this then suggest that lab rats and pigeons—whose behavioral choices adhere to the matching law in a manner similar to humans—have free will? Sapolsky also incisively critiques the “top down” notions of indeterminacy-induced free will, i.e., that some of the randomness that bubbles up is filtered by an “agentic” self; that the agentic self reaches down to the subatomic level and “messes with” the randomness in the system such that free will is exhibited. Skinner ( 1971 , 1974 ) would agree with Sapolsky: these top–down approaches appear to employ a homunculus to explain the behavior that is emitted. In addition to quantum indeterminacy, Sapolsky examines chaos theory and emergent complexity as two other scientific theories that introduce elements of the unknown into the prediction of behavior. He contends that chaotic unpredictability does not mean undetermined; rather, certain types of predictability are impossible due to measurement error and are “deterministically unpredictable” (p. 149), i.e., they embody physical but not epistemic determinism. Likewise, emergent complexity—in which single elements spontaneously self-assemble into a complex entity with unique characteristics—does not imply lack of determinism, because, in contrast to Mitchell ( 2023 ), Sapolsky insists the emergent state is still constrained by the nature and limits of its constituent parts. His bottom line for both theories: unpredictability does not mean undetermined! 7 The role of experience is addressed within, but not really the focus of, Sapolsky’s biological reductionistic thesis. He is interested in learning only as it pertains to the neural level and uses respondent conditioning as an example to elucidate what is happening neurobiologically when a Pavlovian response is acquired. There is no mention of Skinner or operant conditioning; rather, he emphasizes cross-species similarities in learning. Epigenetics is a second way that experience alters our neurobiology. Sapolsky spends considerable time discussing how early life experiences cause durable changes in gene expression (regulation) in specific parts of the brain, e.g., how childhood stress produces more glucocorticoids that result in a less developed frontal cortex that then manifests as decreased impulse control as an adult, how early excess testosterone exposure leads to a highly reactive amygdala that then increases aggressive responses. True to his liberal, hippie roots, he avers that “while a criminal can be dangerous, the poverty, bias, systemic disadvantaging, and so on that produce criminals are more dangerous” (p. 351). As one incarcerated juvenile put it: “We ain’t choose the streets. The streets chose us” (Tucker & Durbin, 2024 ). In Sapolsky’s view, the ability of brains and behavior to change bolsters the deterministic argument. “(W)e don’t change our minds. Our minds, which are the end products of all the biological moments that came before, are changed by circumstances around us.... When our behavior changes... it involves the same molecules, genes, and mechanisms of neuronal function... as when a sea slug learns to avoid a shock administered by a researcher” (p. 269, emphasis in original). What this means, Sapolsky argues, is that society’s localization of moral responsibility in supposedly free will is tragically misplaced. His progressive views emerge in full force in the second half of the book, as he argues that people are not morally responsible for their bad behaviors—similar to how contemporary society has now removed moral culpability for norm-breaking behaviors associated with epilepsy, schizophrenia, autism, and even in some cultures, witchcraft. He supports, as Skinner ( 1971 , 1974 ) does, behavioral accountability without moral responsibility, focusing on the social determinants of criminal behavior, and argues for a rehabilitation-centered public-health quarantine model. And again, like Skinner, he is critical of retributive punishment, which he sees as always immoral yet a high probability response due to its being rewarding to the punisher(s) via activation of dopamine neural circuitry. Thus, his perspective is similar to that of Skinner ( 1971 , 1974 ) but on a different level of analysis: ... the free will you supposedly exercise in choosing... the you who sits in a bucket in your brain but not of your brain.... When viewed as evidence of free will [behaviors that are said to show grit are] a compatibilist playground of blame and praise. It seems so hard, so counterintuitive, to think that willpower is made of neurons, neurotransmitters, receptors, and so on. There seems to be a much easier answer—willpower is what happens when that nonbiological essence of you is bespangled with fairy dust. (p. 93) Like Skinner, Sapolsky argues that advances in scientific knowledge have etiolated conventional notions like meaning, praise, blame, worth, and even hatred. Why something happened is because of what happened just before and just before and just before... in “an empty, indifferent universe in which, occasionally, atoms come together temporarily to form things we call Me” (p. 386). Sapolsky writes in an engaging, passionate, and often personal manner. He provides accessible detail to explain behavior in biological/biochemical terms but also offers concrete examples and draws on real-life news stories. His informal conversational writing style coexists with many primitive, but helpful, figures/drawings, often with a request to ignore the scribbled class notes on them. His meticulously referenced arguments draw on an enormous range of disciplines and include examinations of numerous experiments on various levels of analyses. He even includes separate “Primer” chapters on quantum mechanics, chaos theory, emergent complexity. Many pages include footnotes that are often digressive but almost always interesting. Adding to the rewards for the reader, he offers a treasure trove of wonderful quotes 8 and irreverent analyses. 9 Sapolsky ( 2023 ), in the end, offers a persuasive and entertaining examination of free will, with an approach and conclusions that are the antitheses of Mitchell’s analysis. As noted earlier, Sapolsky starts at the moment of the response and works back reductively to distal causal factors including the start of evolution; Mitchell begins at the onset of evolution and moves forward in time to the development of complex behavior. Sapolsky’s biological reductionism insists that free will requires nonphysical dualism; Mitchell views free will as a neurologically complex ability to act nondeterministically. In fact, Mitchell argues that deterministic theories of any sort imply predetermination, an issue Sapolsky doesn’t address. Thus, after reading these two books, two core questions remain: Is free will without dualism possible? Is determinism without predeterminism 10 possible? We turn, albeit indirectly, to these questions in the next section. A Conciliation (?) of Sapolsky and Mitchell So, we have heard the arguments, and there are elements of each argument that would seem consistent with the world view of today’s science of behavior: Mitchell’s stance is entirely consistent with the notion that there is variability inherent in responding due to ontogenic selection mechanisms, as well as the idea that organisms act upon their environment just as environments influence organisms, and both change as a result of the dynamic interaction. Sapolsky also agrees with Skinner’s repudiation of mental-way stations in causal explanations and with his position that society should not hold people morally responsible for their actions. We ourselves obviously make choices among the possibilities—are those choices determined or free? What do you think? But, if you think your behavior is determined, what does it matter what you think? Indeed, if you think your behavior is determined, why do you bother to think at all? It is perfectly possible to get by in the modern world without doing that, as you have undoubtedly observed. Like some of your neighbors, you might even be happier if you stopped thinking. But if you have to make a choice, it makes some sense to think about it: It gives you a chance to ponder the options for action. But why ponder? Maybe you could optimize your happiness. Dear departed Uncle Lou left you $10,000. Gasp! (You never really liked him; whatever made him do it?). OK. Do you put it down in the GigaLottery; or down on payment for your first house? What does your partner think? Does it matter, if their behavior is determined, what s/he thinks? If s/he thinks? Does it matter what your response to it is? How do you ponder it? Can two ponder together? If so, is that difficult or fun? Or both? And, in the end, does it matter? And how could it matter, after all, if we are determinists? This silly daytime TV melodrama (“stay tuned,” we say, attempting to determine the behavior of your remote) exposes the difficulty of taking a hard determinist position on choice—and choice is what the issue of determinism versus freedom is about. Many issues here, and their name is “Levels,” as discussed in detail below. Both Sapolsky and Mitchell do levels brilliantly. Sapolsky, unremittingly and forcibly, shows how at every level, from your dorsolateral prefrontal cortex to your socioeconomic class to your date of birth, your behavior is overwhelmingly determined, by evolution, by physiology, by sociology, by family, by friends, and by faith. Mitchell, although acknowledging these powerful causal factors, finds “wiggle room” at each of the levels—enough for “agency between the cracks.” It is not surprising that Sapolsky dismisses the idea that such wiggle room provides the opportunity to develop genuine agency. Random factors provide no evidence for free will. Probabilistic determinism is a roll of the dice, not a free choice. Imagine again a world without free choice, as has Ted Chiang ( 2005 ), who created a deterministic world—not one where major choices are deterministically preempted, but where trivial ones (lever-pressing) are predicted. He noted, as we have above, that: “There have always been arguments showing that free will is an illusion, some based on hard physics, others based on pure logic. Most people agree these arguments are irrefutable, but no one ever really accepts the conclusion. The experience of having free will is too powerful for an argument to overrule” (p. 150). It requires a demonstration. His operant button gives it; it predicts your pressing by 1s, no matter what you do (by using a “negative time lag”). Use of the button leads to desperation, trauma and suicide: If all is determined, why bother [to live]? Then a message is sent: “It's essential that you behave as if your decisions matter, even though you know that they don't. The reality isn't important: what's important is your belief, and believing the lie is the only way to avoid [death]. Civilization now depends on self-deception. Perhaps it always has” (p. 150). But, knowing that your choice is determined, why did he bother to send the message? “Because I had no choice.” 11 Hard determinism leads to hard outcomes. Is the alternative to “believe the lie?” To swallow the pill? Or is it a lie? When polled in a recent behavior-analytic symposium on these issues, the overwhelming majority of the audience voted that our behavior is determined. Only one individual of perhaps 100 voted “free.” Perhaps they all “had no choice” in that decision. Perhaps the majority had no choice because they have been taught that determinism is the scientifically correct attitude. Had they been taught otherwise, would they have voted otherwise? If determinism is true, then, having been taught that we are free, they may have voted that we are free agents, and voted against determinism because of those “Sapolsky” causes. But—is determinism really the scientifically correct attitude? What are the data that support that assertion? Everyday experiences belie the thesis: Play Rock-Paper-Scissors with your niece or nephew. Scientists (should) attend to the ubiquitous data that often evidence unpredictability, even apparent free choice, both in humans and other animals. Darwin recognized the fundamental importance of choice as the second major force of selection, as voiced by Kull ( 2023 ) in “Choices by organisms: on the role of freedom in behaviour and evolution”: Sexual “characters in the higher classes have been acquired through sexual selection, which depends on the will, desires, and choice of either sex (Darwin, 1871 , p. 321, emphasis added)” (Kull, p. 556). The guys come to a lek, and strut. The gals come, look, and choose. On the other hand, behaviorists can find that there are causal factors that play a role in outcomes. The whole purpose of functional analysis is to find those factors. Results are never perfect, but there are causes that often can be engaged to effect behavior change. We are scientists and practitioners because we can have efficacy—we can intervene to change things. The ability to intervene to change subsequent events is a hallmark of causal efficacy (Pearl, 2009 ; Pearl & Mackenzie, 2018 ). If you have intervened to change behavior, you are a cause—you had to collect and evaluate data, form a hypothesis, and design an intervention. Your action was agential: you were an agent. Was all of this in the cards already, or did you play an essential role? How can we believe that we are effective agents, and at the same time that it was all determined beforehand? The deterministic attitude that grew during the Enlightenment was a necessary antidote to the gods and demons that, ever since the Greeks, meddled in the orderly course of nature. The nascent science could not predict their whims, which were always a romantic ad hoc “explanation” of events. Rule them out! Assume orderliness! Believe in a deterministic world and do science, as its name and methods evolved to become. This is pragmatic. But, what about individual choice? Killeen and conspirators (Killeen et al., 2024 ) reconcile these arguments by representing action as based on nested feedback control systems, ranging from those clearly deterministic to those clearly volitional. Negative feedback minimizes deviations from setpoints (goals) at each of the levels. Their theory was inspired by the analysis of Rosenblueth et al. ( 1943 ; hereafter RWB). Norbert Wiener, the inventor of modern feedback systems and their name, Cybernetics , worked to clarify the concept of purpose: the proper model for purposive behavior, in their eyes, was that of control systems. Not all behavior that is goal-directed is purposive, however (Skinner, 1984a , b , 1985 ), nor is all purposive behavior an operant. RWB define behavior broadly, as “any modification of an object, detectable externally” (p. 18); this rules out a rock on the ground, but not a falling leaf. How does a falling leaf behave? Its form interacts with the breezes and carries it to a whimsical rest on the ground. RBW divide active behavior into two classes: “purposeless (or random) and purposeful” (p. 18). By purposeful they mean that “the act or behavior may be interpreted as directed to the attainment of a goal.” Purposeful action bifurcates into two kinds: teleological and nonteleological. Teleological systems are guided by feedback. Feed-forward systems, following a template for action, are not teleological. They are goal-driven: the goal of the frog’s tongue-flick (Fig. 1 ) is to apprehend the fly. Accurate though the movement might be, it is ballistic, not corrected en route to that goal. Mayr ( 1992 , p. 127) calls this level “teleonomic”: “The key word in the definition of teleonomic is program ... coded or prearranged information that controls a process (or behavior) leading it toward a goal... a set of instructions... the goal of a teleonomic activity does not lie in the future, but is coded in the program” (p. 128). And that program may have been written by evolutionary processes, or by the hand of an experimenter shaping the behavior of her dog. Fig. 1. Open in a new tab Increasingly complex control systems Within the teleonomic category, there are two subclasses: “Closed” and “Open.” Most such programs are closed—hard-core reflexes and instincts. In open teleonomic systems, the event that triggers the instinctive response may be learned or changed by experience, motivation, and context (Timberlake, 1988 ). Imprinting and classical conditioning exemplify open teleonomic systems. Teleological systems stabilize performance with negative feedback, compensating for perturbations that threaten achievement of the goal. If a house cools too much, a thermostat may start a furnace by comparing the ambient temperature to a set-point adjusted by the homeowner. Hull’s drive-reduction principle is an early version of such a regulatory system. The Rescorla Wagner model of conditioning is also an error-correcting system (Ghirlanda, 2018 ; Rescorla, 1987 ; Rescorla & Wagner, 1972 ), as are regulatory models (Hanson & Timberlake, 1983 ; Staddon, 2013 ; Timberlake & Allison, 1974 ). A dog following a scent (Fig. 1 ) oscillates around the trail, feedback keeping it on the path—but not extrapolating that path. A cat chasing a mouse, however, will typically lead the prey, forecasting where it will be in a few seconds, and aim there. 12 These are higher-ordered feedback systems. As the order increases, we get closer and closer to the performance of sentient creatures such as ourselves. When operants become habitual (Dickinson, 1985 ), they descend to closed teleonomic systems—to automaticity. Consciousness abandons processes where it is no longer needed. The huntsman following the hound can focus on it; but should he stumble on a root, he will refocus on that; and perhaps on the profitability of continuing the chase. Such changes in emotional states, often caused by unpredicted changes in the context, raise the system back to full volitional processing, where alternate action plans are considered. At the highest level is the brain’s model of the agent, familiarly known as the self . 13 When aroused out of open teleonomic functioning, the self must reconsider means and ends. It does this by simulating action plans, using the same neural systems it uses to bring them about. The simulated stimuli and responses—the ideas and plans—are conscious, to approximate such perceptions as experienced in real time, which verisimilitude gives them their hedonic value, on which choice is based (Hirschman & Holbrook, 1982 ). Positive feedback plays a key role in these complex adaptive systems: It focuses and holds attention on the most salient percepts and goals, permitting the self-organization of action plans. The self is not a separate entity, but a quorum of command modules competing for dominance. The authors show how this theory corresponds to Cisek’s ( 2007 ) “affordance competition hypothesis” and Grossberg’s adaptive resonance theory ( 2021a , b ). All of the lower levels up through teleonomic systems are determined by their history and context. Volition emerges when the system must change the governing script and make a choice among different potential actions. The options and their hedonic values compete in the theater of the mind. This is not a Cartesian theater, it is a copy room where multiple drafts, both of perceptions and action possibilities, compete: “a parallel stream of conflicting and continuously revised contents” (Dennett & Kinsbourne, 1992 , p. 183). Thus, in Killeen et al. ( 2024 ) analysis, habitual behavior is determined by history and context. But when challenged with a goal which habitual responses cannot achieve, all relevant potential responses raise their voices. Baer et al. ( 1968 ) called these command modules “guests”; Ainslie ( 1992 ) called them “interests.” There are many other names for them. Skinner ( 1953 ) spoke of"precurrent behavior."“This type of behavior"changes either our environment or ourselves in such a way that'consummatory'behavior occurs"(1968, p. 121),"makes subsequent behavior more effective"(1968, p. 124), and"furthers the reinforcement of subsequent behavior"(1969, p. 137, as cited in Polson & Parsons, 1994 , p. 427). These drafts are precurrent responses, writ very small and fast. Contingent on reinforcement histories, they compete for expression. Those that are most strongly conditioned, or most salient in that context, will win. Looking backwards, we can often understand which of these causal factors won, and why. We can often validate a deterministic chain of causality. Looking forward, however, it is often impossible to predict whether it will be rock, paper, or scissors. The very light finger of attention on the multiple drafts of percepts and potential action plans, with all of attention’s vicissitudes—with all of its swerves—tips the balance in an often-unpredictable way. Once having looked, attention is often captured, and this positive feedback loop then captures action. Looking back, determinism can often be validated; looking forward, our command of attention gives us freedom of choice—a choice that is often unpredictable. This is because, until we savor the actions, neither we nor anyone else is likely to know which will be most appealing at this brief moment in space and time. They remain probabilities until one captures our attention and action. This asymmetry pervades even the physical world. The basic particles of physics exist as probability amplitudes. Upon interaction with other waves or particles—upon observation—they condense into particles. Looking forward, only probabilities; looking back, real particles. This standard view in physics is offered primarily as an analogy; we are not saying that our choices are affected directly by those quantum fluctuations. It illustrates that nature changes, depending on whether it lies ahead of us or behind us. Prospect is not retrospect in reverse. However, we also point out that the conventional dismissal of quantum phenomena as inoperative at the macro-level is being challenged with increasing sophistication in philosophical analyses, theoretical proposals, and empirical investigations, most frequently in regard to human consciousness and higher-order cognitive capacities (e.g., Gao, 2022 ; Musser, 2023 ; Stapp, 2017 ; Zhi & Xiu, 2023 ). Although every approach to the quantum analysis of consciousness has problematic elements to it, several also may offer great promise in furthering our understanding of human choice behavior (Stanford Encyclopedia of Philosophy, 2025 ). Kerskens and Perez ( 2022 ), for example, found suggestive evidence of “entanglement mediated by consciousness-related brain functions. Those brain functions must then operate non-classically, which would mean that consciousness is non-classical” (Abstract). Kerskens (Trinity College Dublin, 2022 ) strongly echoes our probabilistic forward-looking agenic argument:"Quantum brain processes could explain why we can still outperform supercomputers when it comes to unforeseen circumstances, decision making, or learning something new” (para. 9). Killeen et al.’s ( 2024 ) provocative synthesis suggests that the balance pans are on the average level, but it is a dynamic equilibrium. Both Sapolsky and Mitchell are right, even if they would not agree that that is possible. We are, indeed, products of our patrimony—our genetics, our epigenetics, our parents, our neighborhood, our friends. Cavalli-Sforza and Feldman ( 1981 ) showed that some of these determinants were vertical—from parents—such as religion and politics, which most kids receive from their parents. Others, such as style, are horizontal—adopted from their peers. The determinants are pervasive, nonetheless. But not all-pervasive. Reflexes—physical and mental—control most behavior: Unreflected habitual responses. But if we get in trouble—are surprised, things don’t add up, we cannot believe what we are seeing, we must take stock; we must do that difficult thing, and stop to think. Then, and only then, do we truly become agents—the arbiters of our next action, not predictable by others, and often not by us. We put the light beam of attention on one of the competing command modules, and lean in. We act, as agents, with a sense of autonomy, and make a choice—thereby exerting what Sheldon ( 2024 ) would call free will. Circling back to Philosophy: Concluding Comment Readers will not be surprised to learn that the authors of this article take differing positions on determinism and free will, given the durability of the debate and seeming inability to resolve it to everyone’s satisfaction. Killeen et al. ( 2024 ) suggest an intriguing way to, if not fully resolve, at least present the argument in fresh terms that may lead to further insights. For instance, their distinction between past determinism and present free (or perhaps just unpredictable?) choice, mimics the quantum physics core tenet that only with observation does the position and momentum of an electron become realized. Unpredictability is also consistent with emergent complexity and chaos theory. Further, Killeen et al.’s abandonment of a binary model suggests that their perspective is not compatibilism but rather (dare we say?) a unique hybrid comprising the relatively new revisionist perspective (cf., Fischer et al., 2024 ) with the traditional hard determinist one. This revisionist-determinism approach, which also is consistent with Slife et al. ( 1999 ), could be labeled probabilistic determinism : it would recognize that, whereas the past is determined, but that the present offers us situations that have response options of varying probability. In an ideal evaluation we will assess these kinds of situations rationally, selecting the response option that is most likely to maximize our happiness—“the cognitive and social function” of agency, as Vargas puts it (Fischer et al., 2024 ). 14 So, dear reader, does a probabilistic determinism stance make sense to you? Will it advance thinking and research on this debate? Given the widespread belief in free will and personal agency, we suggest it might be a more palatable version of determinism: one that still attributes moral responsibility to the actor while highlighting the interplay of hard determinism that impacts—and very likely constrains—but does not eliminate rational decision making and choice. It implies that prosocial actions are more likely when individuals have a wide range of capabilities available to them to respond flexibly and effectively to surprising and uncertain situations (Biglan, 2015 ). And, further, such a position also has implications for engaging in social action—for expending limited time and energy to try to change cultural practices, improve society, and intervene to promote the well-being of others. If we adopt a probabilistic determinism position, we can appreciate that decisions to engage in such social change efforts are rationally, though perhaps unpredictably, selected—and yet retrospectively determined. As with individual responsibility, such efforts to change systemic injustices will rely significantly on change agents possessing flexible problem-solving skills that facilitate adaptation to the inevitably surprising environmental demands and challenges they will encounter as activists. This view also suggests that grand cultural design schemes like Walden Two (Skinner, 1948 ) are best thought of as guides to be modified in response to changing circumstances rather than blueprints to be followed diligently. From this perspective, effective social action in one’s field or community, like individual social responsibility, is a viable goal even if, at the end of the day, it is all just physics. Thus, we may not be able to predict what will happen next—but we are confident that its analysis will be much more informed and sophisticated by those who digest both Sapolsky’s and Mitchell’s provocative theses! They will cause you to think in new and different ways about your own behavior, as well as that of other individuals interacting with unique, multilayered contingencies as a part of larger communities. It will expose you to new causal factors. Will either position determine how you then act or the choices you make? We hope so—what do you think? And does that really matter? We think so—even if we do not yet know precisely whence our thoughts and intentions originate—we believe they do have causal efficacy! Author Contributions All authors contributed approximately equally to this article and have agreed to the order of authorship as indicated on the title page. Funding No funding was received to assist with the preparation of this article, unfortunately. Data Availability The data that support the discussion in this article are in previously published literature, and everyday life. Compliance with Ethical Standards Conflicts of Interest On behalf of all authors, the corresponding author states that there are no conflicts of interest. The authors have no relevant financial or nonfinancial interests to disclose. Footnotes 1 For example, reducing the belief in free will may be related to increased conformity (Alquist et al., 2013 ) and possibly greater cheating (Vohs & Schooler, 2008 ; but see Nadelhoffer et al., 2020 ). 2 A minority of libertarians adhere to the position that indeterminism means randomness and lack of predictability rather than rational agentic choice—a conceptualization of free will of dubious value and desirability (cf. Sapolsky, 2023 ). 3 Skinner ( 1971 ) argues, for example, that “(a)utonomus man serves to explain only things we are not yet able to explain in other ways (p. 12), a person “is autonomous in the sense that his behavior is uncaused” (p. 17), and (p)ersonal exemption from a complete determinism is revoked as a scientific analysis progresses” (p. 18). 4 Sheldon conceptualizes his model as compatibilist. 5 And, as we will shortly discuss, Sapolsky too is not distressed that nothing can be predicted with certainty! 6 As we have seen, Mitchell’s ( 2023 ) elucidation of compatibilist free will does not require that neurons’ actions are completely uninfluenced by all the uncontrollable factors that came before. 7 Sapolsky doesn’t address the potential of artificial general intelligence to enhance predictions in general but would appreciate recent AGI achievements that suggest exactly that. For example, Lam et al. ( 2023 ) developed a machine learning-based method that was trained directly from reanalysis data of past atmospheric conditions to predict hundreds of weather variables globally over the next 10 days in less than a minute, including severe weather events, with high resolution and an accuracy that was better than current methods in over 90% of the 1,380 targets. Sapolsky might contend that with future iterations of “artificial super intelligence” (cf. Friedman, 2024 ), predictive accuracy for a wide range of phenomena will increase to close to 100% for events farther and farther in the future, including human behavior. 8 For example: The Indian neurologist Rajendra Kale: “The history of epilepsy can be summarized as 4000 years of ignorance, superstition and stigma, followed by 100 years of knowledge, superstition and stigma” (p. 312) and the sociologist Laurence Peter: “Psychiatry enables us to correct our faults by confessing our parents’ shortcomings” (p. 321). 9 Examples: On the “psychodynamic royalty” fleeing Hitler in the 1930 s: “With their confident, authoritative air of European intellectual superiority, they proceeded to wow the yokels of American psychiatry and become the dominant model of thought” (pp. 320–321); On research funding: “... many a scientist says, in effect, ‘Oh please, please, let the loved one of some Republican senator come down with the awful disease I study so there’ll finally be enough funding for us to figure out how to cure it’” (p. 333); and perhaps over the line occasionally: “The psychoanalytic scumbags even developed a sneering, pejorative term for families (i.e., mothers) of schizophrenic patients who tried to dodge responsibility by believing it was a brain disease: dissociative-organic types ” (p. 329). 10 Predeterminism means that the evolution of all events in the universe is inevitably fixed for all time by their starting values: replaying the tape of that evolution would always arrive at the same state. 11 We believe that this vignette was inspired both by the work of Benjamin Libet ( 1983 , 1985 , 1999 ), who, as noted earlier (and along with others), showed that a readiness potential preparing an act occurred before we were conscious of the decision to act; and that of Taylor and Brown ( 1988 , 1994 ) showing the health benefits of positive illusions. 12 Weiner devised anti-aircraft control systems in World War II that accomplished just that feat. 13 Such a model is essential to locate the person in the context. 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