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.