René Descartes: Life, Metaphysics, and the Mind-Body Problem

René Descartes: Life and Philosophical Foundations

René Descartes was born on March 31, 1596, in La Haye, Touraine, France. He belonged to a family of minor nobility; his father, Joachim Descartes, served as a Counselor in the Parliament of Brittany. Due to the early death of his mother, Jeanne Brochard, a few months after his birth, Descartes was brought up by his maternal grandmother, with a nurse who remained linked to his life.

His famous work, Discourse on Method (1637), was followed by The Dioptrics, The Meteors, and Geometry, which served as tests of this new method. The success of these works led him to devote himself entirely to philosophy. Descartes, often in poor health and accustomed to staying in bed until midday for his writing, unfortunately caught a cold and died of pneumonia in Stockholm on February 11, 1650, at the age of 53.

Descartes's Metaphysics: The Three Substances

In his metaphysics, Descartes established absolute doubt as his primary method. Through this rigorous process, he arrived at truths that were clear and distinct, identifying three fundamental types of substance:

• The Infinite Substance: God, the ultimate reality and source of all being.
• Thinking Substance: Man, characterized by thought, consciousness, and the ability to reason.
• Extended Substance: The world, defined by its physical dimensions, spatial occupation, and adherence to mechanical laws.

Cartesian Anthropology: The Mind-Body Problem

In his anthropology, Descartes sought to explain the intricate connection in humans between extension (the physical body, embodiment) and thought (the soul). For Descartes, man is composed of both mind and matter, soul and body. He conceived mind and matter as two distinct and antagonistic entities.

The body, as part of the material world, is governed by the laws of physics. Descartes viewed physics as deterministic and mechanistic, seeing the body as part of a grand machine, a vast mechanism that operates like a clock based on pulleys, gears, levers, and wheels. This operation adheres strictly to the principle of causality and the laws of physics. This concept of the universe implies a certain physical determinism, meaning the body is limited in its behavior by these physical laws and, consequently, possesses no inherent freedom.

The soul, however, is reason and thought. It is, as Descartes famously stated, "that which discovers, by sheer thinking, my own existence as something that thinks." The soul is an understanding that can conceive, but it is also capable of admiring, desiring, hating, affirming, denying, doubting, and, above all, acting in freedom.

Reconciling Dualism: The Pineal Gland

The central problem for Descartes was how to reconcile these two profoundly different substances. While he had established a sharp separation between mind and body, the challenge remained: how do they coordinate? It is clear that in humans, body and soul have a connection, as external stimuli affect the soul, and the body obeys the designs and desires of the soul.

Descartes proposed that this "speaking machine" (the body) communicates with the thinking entity within it (the soul) through the pineal gland. Located in the center of the brain, Descartes believed this gland housed the soul. From there, the soul connects to the body, modifying the movements of particles (referred to as "animal spirits") that, as they pass through the veins and nerves, trigger the physical processes that generate movement.

Descartes's dualism, though taken further than Plato's in its distinct separation, nevertheless offers an explanation for this interface that has been described as both incredible and somewhat simplistic.