La Mettrie

Julien Offray de La Mettrie (1709–1751) was a French physician and philosopher whose L'Homme Machine (1748) represents the most radical extension of mechanical philosophy: the claim that the human mind, no less than the body, is entirely mechanical. La Mettrie argued that thought is a function of the brain, just as digestion is a function of the stomach, and that the apparent unity of consciousness is an emergent property of organized matter.

His position was the logical conclusion of Descartes' mechanistic physiology, stripped of its dualist escape clause. Where Descartes had quarantined the mind in an immaterial substance, La Mettrie insisted that the mind is matter organized in a particular way. The implications were explosive: no soul, no free will in the traditional sense, and no essential difference between human cognition and the operations of a sufficiently complex machine.

La Mettrie was persecuted for these views and died in exile in Prussia. His work anticipates contemporary debates about artificial intelligence and the philosophy of mind: if a machine can think, La Mettrie asked, what remains of the special status of human consciousness?

La Mettrie was not a nihilist. He was a physician who noticed that the brain, like the liver, could be affected by disease, diet, and fever — and concluded that thought has the same material basis as digestion. The argument was empirical, not mystical. We have spent three centuries trying to refute it and have not succeeded.