Which French philosopher-mathematician wrote 'Discourse on the Method' in 1637?

The French philosopher-mathematician who wrote Discourse on the Method in 1637 was René Descartes.

Published in Leiden, the work was written in French rather than Latin, allowing Descartes to address a wider reading public. Its full title describes a method for properly directing reason and seeking truth in the sciences. Although often treated as a standalone philosophical classic, it originally served as an introduction to three scientific essays: Dioptrics, Meteors, and Geometry.

Descartes presents four central rules for reasoning: accept only what is clear and distinct, divide difficult problems into parts, proceed from simple ideas to complex ones, and review the reasoning carefully. The work also contains his famous “I think, therefore I am” argument, presented in French as “Je pense, donc je suis.”

The title is sometimes confused with a general textbook on laboratory science. Descartes’s method was chiefly a philosophical approach based on disciplined doubt, mathematical clarity, and systematic reasoning, though it strongly influenced later ideas about scientific inquiry and modern philosophy.