Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and Ideas · Sean Carroll

348 | Jessica Riskin on Jean-Baptiste Lamarck and Life as Creative Agency

March 23, 2026·1 hr 15 min·5 clips

Darwin never questioned Lamarck's idea of inheritance of acquired characteristics—it's in every edition of Origin of Species.

Sean Carroll opens the episode with a reflection on how scientific knowledge passes through cycles of simplification and complication. He uses evolutionary biology as his example: Darwin and the modern synthesis produced a powerful clean theory, but now epigenetics, microbiome inheritance, and mitochondrial DNA are restoring complexity. That context sets up why Lamarck, long dismissed as a cautionary tale, is worth revisiting. Jessica Riskin is a Stanford historian of science whose earlier book The Restless Clock traced a centuries-long argument between two models of living beings: the passive machine, designed by outside forces, and the active self-creating organism. She explains that her Lamarck book, The Power of Life, grew out of realizing that Lamarck was the central figure she had underemphasized in the first book. Riskin makes a counterintuitive historiographical move: she argues that the passive-machine tradition was not the secular materialist camp but the theological one. Descartes, Boyle, Ray, and William Paley all used mechanical design in nature to prove God's existence. The active-organism tradition — Lamarck, La Mettrie, Diderot — was the genuinely atheistic wing, because it sought to explain how living things could make themselves without any external designer. Riskin's punchline: Richard Dawkins is intellectually the heir to Paley, not to Lamarck. Carroll asks Riskin to narrate Lamarck's biography, and she delivers a vivid story. Lamarck was born in 1744 in Picardy, the eleventh child of impoverished military nobility. He fled seminary school on his mother's horse to fight in the Seven Years War, then became a botanist under Buffon's patronage. After the Revolution, he was given the least desirable professorship at the new Museum of Natural History: insects and worms, a category so vast it included mollusks. Lamarck renamed the field invertebrate biology, coined that term, and named over 6000 species. He also established the first government weather bureau by systematizing cloud taxonomy — until Napoleon shut it down. Napoleon despised Lamarck. Riskin recounts the scene in 1809 when Napoleon snatched Lamarck's freshly published Philosophie Zoologique from his hands and publicly humiliated him, reducing the elderly naturalist to tears. Napoleon's inner circle of scientists — Cuvier, Laplace, Lavoisier's successor — were all hostile. Cuvier, a devout Lutheran, rejected evolution entirely and was assigned the task of writing Lamarck's eulogy after his death; the result was a famously vicious piece of prose. Riskin then explains why the passive model won. In the late 19th century, German Darwinist August Weismann chopped off mice tails for many generations, showed the offspring still had tails, and declared Lamarckian inheritance refuted. Riskin notes that Weismann himself acknowledged this was a straw man — neither Lamarck nor Darwin claimed amputations were inherited — but the experiment was a powerful rhetorical gesture and entered textbooks as definitive refutation. Darwin's own Lamarckianism is the episode's sharpest revisionist claim. Carroll and Riskin discuss at length how Darwin called the inheritance of acquired characteristics the inherited effects of use and disuse, included it in every edition of The Origin of Species, and was himself torn between the Paley passive model and the Lamarck active model. The modern synthesis expelled Lamarck; Darwin himself never did. The conversation closes on the contemporary relevance: epigenetics and microbiome research are producing empirical results that fit the Lamarckian active-organism frame better than strict neo-Darwinism. Riskin does not claim vindication for the specific mechanism of inheritance of acquired characteristics, but argues the philosophical shift — toward organisms as self-creating agents rather than passive vehicles of genes — is long overdue.

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