Julien Offray De La Mettrie, respected French physician of his time, created a scandal in the mid-eighteenth century based on his viewpoints of materialistic philosophy. Humans, though a highly complex living machine, behave automatically according to La Mettrie. He notes that physical phenomena, consciousness, emotion, will, memory, and moral sense are ultimately determined by physical mechanistic factors.
La Mettrie held that the contrasts between humans and other mammals are simply a matter of varying brain structures: “Man is not moulded from a costlier clay; nature has used but one dough, and has merely varied the leaven.”
When Man a Machine was published in 1748 in Leiden it created quite the stir. This was a time of intellectual verve and the application of reason to all facets of life. His work was so outspoken that La Mettrie was forced to flee the country. This was the second time he had to flee due to his writings on materialistic philosophy; the first was after he had published The Natural History of the Soul in 1745. He eventually found refuge in Berlin with his friend Frederick II of Prussia, becoming the court reader and physician to the king.
La Mettrie’s work had an impact on behavioral science, creating a footing for behaviorist psychology as well as modern materialism.