Interactionism

• Interactionism is discussed by Descartes in 'Philosophy of the Mind'
• Descartes claimed that the pineal gland was where the metaphysical soul interacted with the physical body
• Neuroscience says that the pineal gland produces melatonin and has nothing to do with the soul
• Descartes had no initial evidence for the pineal gland connecting the body with the metaphysical
• Descartes did not have the benefit of modern biological science
• Descartes's proof

  • The pineal gland sits between the 2 hemispheres
  • Connects the brain with the metaphysical (mind)
• Descartes never explained how the interaction takes place
• The real purpose of the pineal gland is to produce melatonin that regulates sleep rhythms
• Evaluation of Descartes's interactionism

  • Outdated- 17th century
  • Inaccurate- Takes a mechanistic view of the physical universe, believing that everything needs a physical location
  • Based on speculation
• Descartes came up with interactionism before Newton discovered gravity, the idea that everything known had to be physical or have a physical place was standard