Rene Descartes

Modified: 2025-01-08 12:37 PM

xxxx

• Rene Descartes and Francis Bacon broke from Scholasticism but did so differently
  • Descartes searched for secure, universal knowledge that was independent of sensory observations.
  • Bacon promoted the role of sensory observations in his philosophy and proposed a radical form of empiricism called induction.
  • Modern philosophy and psychology are still affected by their competing visions.
• Rene Descartes
  • French philosopher
    • Celebrated Galileo's discovery of Jupiter's moons while in school
    • Soldier
    • Mathematician
      • Analytic Geometry
        • Inspired by fly buzzing in Mersenne's cell
          • Made him conceive of the x, y, z Cartesian coordinate system
  • Inspired by his dreams to reform learning and knowledge acquisition
    • But, he was afraid to offend the Church
  • He wrote: Discourse on Method (plus Dioptrics, Meteorology, and Geometry)
    • Refraction (air/water)-Snell's law video
      • Helped convince Descartes that senses could not be trusted
      • His Rationalism depended on the mind, not observations
    • Descartes' physics did not pass test of time
    • Believed nerves were hollow tubes filled with fluid
      • He was inspired by hydraulic robots
      • Reflex action (graphic)
  • Meditations
    • Descartes wanted to find a foundation for his philosphy
    • When he realized he was thinking he inferred there must be a thinker, he himself. He said:
      • Cogito, ergo sum or "I think, therefore, I am."
      • From that point forward he could build a philosophical system
    • Matter and Mind
      • He divided the world into two parts: mind and body
      • He said they interacted
      • Cartesian dualism or interactionism

Interactionism-the belief that there exists a separation between the physical world and the mental world and that each can affect the other.

• Mind-Body Problem
• External world (size, shape, position, and motion of objects) vs. Internal world (color, sounds, smells, and tastes)
• Cartesian interactionism is only one solution to the mind-body problem
• In this and the next chapter we'll look at other solutions
  • Many of those arose because of the problems with Descartes's solution
    • For example:
      • How and where do mind and body interact
      • Descartes assumed a benevolent God, so he could not rule out that his cogito, ergo, sum was really correct
      • Descartes's system relied on God. Most later philosophers sought to completely separate religion from philosophy
• Descartes' Later Life and Legacy
  • Moved to Netherlands and then to Sweden (to escape Inquisition)
    • Died there soon after
  • Founder of modern philosophy
  • All works placed on the Index

BORDER WITH COMPUTATIONAL SCIENCE (p. 164)

• Analytic Geometry
  • Legend has it that the inspiration for analytic geometry came to Descartes while he was in bed watching a fly buzz around a room.
  • True or not, modern analytic geometry did not spring fully fledged from Descartes’s mind. Instead, he showed that some problems in geometry could be solved algebraically.
  • Later mathematicians developed the now familiar x, y, & z coordinate system using his notation.
  • His contribution to mathematics was profoundly important to the later development of the calculus by Newton and Leibniz.
  • In the 19th century, the x, y, & z coordinate system was named “Cartesian” in his honor (see Figure 5.5).

FYI: DESCARTES AND THE REFLEX (p. 168)

• Descartes attempted to explain reflex action using a hydraulic model.
• To him, nerves were hollow tubes filled with liquid, animal spirits (see Figure 5.6).
• When the heat from a fire became too intense the spirits pushed on the pineal gland, which in turn, sent animal spirits down another nerve tube, moving the affected body part.
• The moving statues moved by water and hydraulic tubes at at St. Germain inspired his model of nerve action.
• Descartes sought to explain reflexes mechanistically in both humans and animals.
• He assignined a mind only to humans. To him, animals had no minds and behaved exclusively as the result of mechanistic principles.

BORDER WITH SOCIAL SCIENCE (p. 169)

• The Mind-Body Problem and Scientific Progress
• The synergy between physics, mathematics, and the mind-body problem proved advantageous to physical science.
• Sciences whose subject matters could be studied by measuring the primary qualities (those unaffected by perception, see Locke, below) only quickly prospered.
• Physics and chemistry developed quickly. Both only needed to examine the physical universe.
  
• Descartes saw natural philosophy (aka, the "hard sciences) as a tree, with metaphysical roots, a philosophical trunk, and branches of medicine, mechanics, and morals.
• For Descartes, psychology and the other social sciences would emerge from moral philosophy.
• That branch of his tree was concerned with passions, their control and methods for directing the will toward good and away from evil.
• Unlike natural philosophy, moral philosophy required study of both mind and body.
• Paradoxically, physics and the other “hard” sciences have had a smoother historical path; they have only had to cope with the body, the external and physical half of the mind-body problem.
• The social sciences, on the other hand, have had to cope with both halves of the problem, a more difficult and bumpy road.

Back to Learning Theory Main Page