Rene Descartes and His Philosophy
A Study of Rationalism and Modern Thought
by: Ulysses Ybiernas | August 20, 2019
René Descartes (1596–1650) is widely regarded as one of the most influential thinkers in the history of Western philosophy. Known as the father of modern rationalism, Descartes revolutionized how we think about knowledge, existence, and reason.
Descartes' Method of Doubt
One of Descartes’ most enduring contributions is his methodological skepticism. In his work Meditations on First Philosophy, Descartes begins by doubting all his previous beliefs, including sensory perceptions and even mathematics, in search of absolute certainty.
“Cogito, ergo sum” — “I think, therefore I am.”
This statement becomes the foundational truth of Descartes' system: even in doubt, the existence of the self as a thinking entity is undeniable.
Rationalism and the Mind-Body Split
Descartes is a central figure in rationalist philosophy, which emphasizes reason over sensory experience as the path to knowledge. He also introduced mind-body dualism: the idea that the mind (a non-material thinking substance) and body (a material extended substance) are distinct and separate.
According to this view, the mind is indivisible and not subject to physical laws, whereas the body is extended in space and subject to causality. This philosophical stance raised major questions about how these two interact, leading to what is now called the “mind-body problem.”
Science and Mathematics
Descartes was also a pioneer of scientific thinking. He believed nature could be understood through mathematics and deductive reasoning. His development of Cartesian coordinates helped bridge algebra and geometry and laid the groundwork for modern calculus and physics.
Criticisms and Lasting Impact
Critics, especially empiricists like John Locke and David Hume, challenged Descartes’ reliance on reason alone. Modern neuroscience also questions dualism by showing strong correlations between mental activity and the brain.
Still, Descartes' influence remains profound. His emphasis on clarity, logical structure, and foundational inquiry set the tone for modern philosophy and science alike.
Conclusion
René Descartes' legacy lies not only in his famous dictum or his mathematical innovations but in his radical rethinking of human knowledge. His insistence on foundational certainty, rational inquiry, and methodological doubt remains a cornerstone of philosophical thought today.