René Descartes

Born: 1596
Died: 1650
Title: Father of Analytic Geometry

The Matchmaker of Geometry and Algebra

Before Descartes, geometry (drawing) and algebra (calculation) were completely separate fields. Geometers used compass and straightedge, algebraists solved equations. Descartes did something revolutionary: he combined them.

Core Contributions - Deep Analysis

Cartesian Coordinate System

Legend has it that he was lying in bed watching a fly dance on the ceiling, thinking about how to describe the fly's position, and thus invented the coordinate system.

The Great Significance: He not only invented the $x$-axis and $y$-axis, but more importantly, he discovered that any geometric figure can be transformed into an algebraic equation.

A circle is no longer just a shape—it is $x^2 + y^2 = r^2$.

This paved the way for calculus, because we could now calculate the rate of change of curves.

Philosophical Thought

His famous saying "I think, therefore I am" also influenced his mathematical style—an extreme pursuit of logical clarity and a spirit of skepticism.

Legacy

Descartes established that mathematics can unify seemingly different fields. His coordinate system became the foundation of modern mathematics, physics, and engineering. Without Cartesian coordinates, calculus, physics, and computer graphics would be impossible.