René Descartes and the Mind-Body Problem
The Father of Modern Rationalism
René Descartes, the creator of modern rationalism, was born in France in 1596. He studied at the Jesuit college of La Flèche but found the education disappointing, considering it outdated and governed by the “principle of authority.” He valued only the mathematical knowledge gained there, appreciating its rigorous principles and demonstrations. This led him to pursue self-education through various sources, including what he called the “book of life.” He traveled extensively throughout Europe and even served in the army.
Descartes’s most notable philosophical works include:
- Rules for the Direction of the Mind
- Discourse on Method
- Meditations on First Philosophy
- Passions of the Soul
- Treatise on Man
Discourse on Method is a groundbreaking text that ushered in modern philosophy and science, significantly impacting Western culture. Descartes introduced a new, mechanistic conception of science. His ideas gradually gained acceptance, despite resistance from the established scholasticism supported by the clergy. Descartes argued that overcoming these challenges required a shift in mindset, not just scientific demonstrations like Galileo’s heliocentric model. This marked a “Cartesian revolution,” profoundly changing our culture.
Descartes is a significant figure in French philosophy, representing national identity. He opposed fanaticism and believed that no philosophy is inherently superior to others. While he valued patriotism, he consistently sought to engage with all those who pursued scientific knowledge.
Published in 1637, Discourse on Method served as a prologue to three scientific essays: Dioptrics, Meteors, and Geometry. Since the 19th century, it has been published independently. Descartes divided his Discourse into six parts:
- Emphasizes the importance of common sense but stresses the need for an efficient, mathematical approach.
- Aims to establish a new, reliable scientific method based on four rules: evidence, analysis, synthesis, and enumeration. Descartes equated truth with clarity and self-evidence.
- Suggests that existing knowledge can be doubted until rebuilt on the solid foundation of his method, requiring a “provisional morality.”
- Introduces the “cogito” (“I think, therefore I am”) as the foundational truth upon which other truths, including God, the world, and the body, can be demonstrated.
- Explains his mechanistic view of the universe, describing living beings as machines made of matter. Humans occupy a higher level due to possessing an immortal soul, the “res cogitans” (thinking substance).
- Expresses his belief in science as a collective endeavor, not an individual pursuit. He envisioned science as a means to human happiness and mastery over nature.
The Mind-Body Problem
The mind-body problem, or the relationship between the spiritual and material, has a long history in philosophical thought. The belief in a soul separate from the body dates back to early humanity. In Greek tradition, at least since Homer, the psyche (soul) was believed to have some existence independent of the body. This belief was reinforced by the Orphic mysteries and Socrates’s belief in the immortality of the soul, which Plato also adopted.
However, Aristotle rejected psychophysical dualism. His hylomorphic theory viewed the soul as the form of the body, inseparable from it. Consequently, Aristotle did not believe in personal immortality and considered psychology a branch of biology.
The mind-body problem has been primarily addressed through two opposing viewpoints: psychophysical dualism and psychophysical monism. Cartesian philosophy revived psychophysical dualism with its doctrine of substances. Descartes distinguished three types of substances: infinite substance (God), thinking substance/res cogitans (thought), and extended substance/res extensa (matter).
Descartes viewed the body as a machine. However, humans possess mental capacities, indicating the presence of a mind or soul. He believed animals lacked thought and were merely machines. But for humans, endowed with thought, the relationship between the res cogitans and res extensa posed a challenge.
Descartes adopted an interactionist dualism, suggesting that the interaction between the immaterial mind and the material body occurred in the pineal gland, a part of the brain. However, this explanation fails to address how something intangible can interact with matter in a specific location. Subsequent philosophers have sought more satisfactory solutions.
In the 20th century, behaviorist psychology denied the existence of the mental, focusing solely on observable behavior as the object of scientific study. Gilbert Ryle, a prominent behaviorist, criticized the “ghost in the machine” notion of the mind and opposed all forms of materialism. He argued that speaking of the mind as separate from the body was a categorical error.
However, since the 1970s, cognitive psychology has replaced behaviorism and revived the consideration of mental phenomena.