La Mettrie, Julien Offroy de

Born Dec. 25, 1709, in St. Malo, Bretagne; died Nov. 11, 1751, in Berlin. French materialist philosopher.

The son of a wealthy merchant, La Mettrie studied theological science, physics and medicine. In Leiden, he studied under H. Boerhaave. He became a regimental surgeon. Falling ill with a fever, he concluded from observations of his own illness that a human being’s psychic activity is determined by his bodily organization. This idea underlay his first philosophical work, The Natural History of the Soul (1745), which provoked the wrath of the clergy and was burned by an order of parliament.

La Mettrie was forced to emigrate to Holland. There he published anonymously his work Man a Machine (1747; new edition, 1960; Russian translation, 1911), which also was publicly burned. In 1748, he moved to Berlin on the invitation of the Prussian king Frederick II. In Berlin he became a member of the Academy of Sciences and published his works, The Human Plant (1748), The Human as More Than a Machine (1748), and The System of Epicurus (1751). He died while testing a new method of treatment on himself.

La Mettrie was the first person in France to give a consistent exposition of the system of mechanistic materialism. According to La Mettrie, there is only material substance; its inherent capacities to feel and think are displayed in “organized bodies”; the state of the body wholly conditions the state of the soul by means of sensory perceptions. La Mettrie rejected R. Descartes’s idea of animals as simple automatons, devoid of the capacity to feel. In his view, man and animals are created by Nature from one and the same “clay,” and man is distinguished from animals only by his greater number of needs and, consequently, greater intelligence; La Mettrie believed the needs of the body to be “the measure of intelligence.” La Mettrie regarded the human organism as a self-winding machine, similar to a clockwork mechanism. In his last works, La Mettrie approached the ideas of evolution, expressing ideas about the common origin of the vegetable and animal kingdoms and about the gradual perfection of matter and of the animal kingdom. He advanced the hypothesis of the existence of zoophytes—plant-animals—which was subsequently confirmed by science.

Developing the viewpoint of sensualism, La Mettrie believed that the external world is reflected on the “screen of the brain.” In ethics, he adhered to a hedonist standpoint, while at the same time according a significant role to the public interest. According to La Mettrie, the development of society is determined by the activity of outstanding people and by the successes of enlightenment; La Mettrie was a partisan of enlightened absolutism. His philosophical ideas exerted considerable influence on D. Diderot, P. Holbach, and C. Helvétius.