Descartes’ Philosophy: A Quest for Certainty
Building a New Foundation for Philosophy
Descartes sought to establish a secure and universal philosophical system, unlike the fallible systems of the past. He envisioned a philosophy grounded in reason, similar to mathematics, that would be free from particular beliefs and customs. This dream of universal reason marked the beginning of modern rationalism, culminating in the Enlightenment.
The Method of Doubt
To achieve this, Descartes employed the axiomatic method, starting with a self-evident axiom and deducing other ideas using logic. He proposed the method of doubt, questioning all ideas until an absolutely certain foundation was found. He doubted sense data, as they can be deceptive, and even questioned the distinction between dreams and waking life.
The Cogito and the Existence of God
Descartes realized that even if he doubted everything, he could not doubt his own existence as a thinking thing: “I think, therefore I am” (Cogito, ergo sum). This became his foundational axiom. To avoid solipsism, he sought another truth within his consciousness and focused on the innate idea of God. He used ontological and other arguments to demonstrate God’s existence, concluding that God, being good, would not deceive us about the existence of the external world.
Dualism and the Mind-Body Problem
Descartes’ philosophy became a dualism of mind (res cogitans) and matter (res extensa). The attribute of mind is thought, while the attribute of matter is extension and determination by physical laws. This deterministic view of physics opened the debate on how the mind and body interact. Descartes proposed the pineal gland as a fictional point of interaction between these two distinct substances.