What was René Descartes like as a person? René Descartes Read more from Chapter Early Modern Philosophy

It is difficult to say. In contemporary terms, Descartes would probably be considered a fearful, anxious, and self-absorbed man with social disorders. He was the only seventeenth-century philosopher who never had a patron or a secure post, and he was not independently wealthy.

Descartes moved to Holland to escape the distractions of Paris, so that he could concentrate on his work. He was secretive about his personal life and moved his household about once a year during a 20-year period. Wherever he was, he conducted experiments, sometimes getting animal organs from local butchers. One account has it that when he studied vision, he literally looked through a calf’s eyes.

Descartes was greatly interested in special foods and diets, possibly as a way to prolong life or even to achieve immortality. At times he was a vegetarian—it’s clear this was not for moral reasons, given his belief that animals are machines—and other times he thought that the secret lay in eggs. With a servant named Helena Jans, he had an illegitimate daughter.

While Descartes’ daughter, Francine, is usually described as illegitimate by biographers, her baptism was recorded in 1635 in the Reformed Church in Deventer. Francine died at the age of five from scarlet fever, and Descartes expressed great sorrow for this loss. Descartes’ motto was said to have been: “A life well hidden is a life well lived.” Another version has it as: “I advance masked.”