Determined: A Science of Life Without Free Will

Determined Review

Determined is Robert Sapolsky’s follow-up to his masterwork Behave, and it takes the argument of that book to its logical conclusion. Behave demonstrated that every human behavior is the product of biological, developmental, cultural, and environmental causes operating across multiple timescales. Determined argues that this accumulation of prior causes leaves no room for the kind of free will that could justify moral responsibility in any robust sense — and that we should revise our institutions accordingly.

The Cumulative Case

The book proceeds by exhaustive elimination. Sapolsky surveys the neuroscience of decision-making (the brain prepares for action before we are consciously aware of deciding), the genetics of behavior (not genetic determinism, but genes interacting with environment), developmental biology, the endocrinology of stress and reward, the role of culture and history — and argues that at each level, causes precede choices in ways that leave no foothold for an uncaused causer. The argument is cumulative: no single study is decisive, but the convergence from multiple directions is, Sapolsky contends, overwhelming.

Sapolsky’s signature move is to ask the reader to “show me the neuron” that acts without itself having been caused — to locate the point in the chain where a decision originates uncaused by genes, hormones, childhood, culture, or the state of the brain a second earlier. There is no such point, he argues; it is causes all the way down, with no homunculus, no uncaused causer, hiding behind the curtain. He marshals the famous neuroscience of readiness potentials (the brain initiating action before conscious awareness), but he is careful not to rest the case on any single contested experiment. The force of the book is its breadth — the sheer convergence of neuroscience, genetics, endocrinology, and developmental biology all pointing the same way.

Where Philosophers Push Back

The philosophical chapter — where Sapolsky engages with compatibilism, the view that free will is compatible with determinism — is the book’s most contested section. Compatibilists argue that ‘free will’ properly understood just means acting from one’s own desires and reasons, without external compulsion, and that this kind is compatible with those desires and reasons being themselves caused. Sapolsky replies that this redefinition doesn’t preserve the moral and legal weight we actually want free will to carry. The debate is genuinely open, and philosophers will find his treatment inadequate; but his larger point — that our intuitive notions of desert and blame go well beyond what the science can support — is harder to dismiss.

Critics have been pointed. Writing in The Atlantic, the philosopher Kieran Setiya praised Sapolsky’s command of the science but faulted him for barely engaging the serious philosophical literature on free will, and others have charged that he effectively defines compatibilism out of existence before the argument begins, or that he offers a “rewarmed” version of an anti-free-will case Bertrand Russell made in the 1940s. The fairest summary is that the science is dazzling and the philosophy is thin — and since the question of free will is at least as much philosophical as empirical, that is a real limitation. Sapolsky tends to treat a hard problem as if the data settle it, when the data mostly bear on a narrower question than the one philosophers actually argue about.

A World Without Blame

The final sections, on what a post-free-will ethics and legal system might look like, are the most speculative and the most important. Sapolsky argues that if no one truly chooses their actions, then retribution — punishment as deserved suffering — loses its justification entirely. He does not conclude that we should release dangerous people; instead he favours something like a public-health or “quarantine” model, in which society still restrains those who cause harm but does so to prevent further harm and to rehabilitate, never to inflict suffering for its own sake. He draws an analogy to how we gradually stopped blaming people for epilepsy, mental illness, or learning differences once we understood their biological roots — and asks why we should not extend that same hard-won compassion to all human behaviour. It is a confronting thought experiment, and one that lingers whether or not you accept its premises. It is a genuinely radical proposal, and Sapolsky is honest that he himself cannot consistently live as though free will is an illusion — that the intuition of agency is too deeply wired to switch off. That candour is disarming, and it points to the book’s real value: whether or not he proves his thesis, he makes a powerful case that our systems of blame and desert rest on far shakier foundations than we like to admit.

Verdict

Determined is Sapolsky’s most provocative book — scientifically rich, morally serious, and philosophically contestable. Read it not as the final word on free will, which it is not, but as a bracing, humane challenge to the reflex of blame that shapes our courts, our relationships, and our judgements of ourselves and others. Even readers who finish unconvinced — and many thoughtful ones will — tend to come away with their certainties loosened, which may be the most any book on this ancient question can honestly achieve. Pair it with Behave, its larger and more celebrated predecessor, for the fullest picture of Sapolsky’s view of why we are the way we are.

Our rating: 4.1/5 — A sweeping, witty, and unsettling argument against free will — strongest on the science, weakest on the philosophy, and valuable regardless of whether it convinces you.

Reading Guides

• Where to Start with Robert Sapolsky
• Behave by Robert Sapolsky — Full Review