Rene Descartes 15961650

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Rene Descartes1596-1650
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Getting to Know You

• French mathematician, philosopher, and physicist
• Founded analytic geometry, the bridge between
  algebra and geometry (and crucial to the
  discovery of calculus)
• Called the Father of Modern Philosophy
• Many elements of his philosophy are Aristotelian
  (in that all things are designed for a final
  result and that there is a purpose for all that
  exists)
• In 1663, the Pope placed Descartes works on the
  Index of Prohibited Books

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Discourse on the Method of Rightly Conducting
Ones Reason and of Seeking Truth in the Sciences

• Published in 1637, Discourse on the Method is
  organized into six parts
• 1.) How to Think Correctly
• 2.) The Method of Science
• 3.) Morals Maxims deduced from this method
• 4.) Proof of God and the Soul
• 5.) Physics, the heart, the soul of man and
  animals
• 6.) Experiments

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Discourse TwoThe Method of Science

• Descartes Method is characterized by four
  precepts
• 1.) Accept only that which you are sure of
  (filter away all that may be in doubt)
• 2.) Divide into as small parts as necessary
  (divide difficulties into as small pieces as
  necessary)
• 3.) Solve the simplest problems first
• 4.) Make as complete lists, tables, and diagrams
  as possible

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Discourse Four Proof of God and the Soul

• Descartes applies his scientific method (outlined
  in Discourse Two) to challenge his own reasoning
  and reason itself
• If each step of the scientific method were free
  from error, the darkest secrets of nature could
  be discovered
• Descartes only needed a single unassailable
  position (a foundation that one can know is true
  without any doubt) from which to begin
• For Descartes, that foundation was the phrase I
  think therefore I am.

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Methodological Skepticism

• In order to obtain truth, Descartes must first
  reject any ideas that can be doubted
• Cogito ergo sum I think, therefore I am
• Descartes concluded that if he doubted, then
  someone or something must be doing the doubting
  because thought cannot be separated from the one
  doing the thinking.
• The very fact that Descartes doubted proved that
  he existed

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The Wax Argument

• Descartes uses the Wax Argument to illustrate why
  truth cannot be gained through sensory perception
• He considers a piece of wax his senses inform
  him that it has certain characteristics, such as
  shape, texture, size, color, smell, and so forth.
  When he brings the wax towards a flame, these
  characteristics change completely. However, it
  seems that it is still the same thing it is
  still a piece of wax, even though the data of the
  senses inform him that all of its characteristics
  are different. Therefore, in order to properly
  grasp the nature of the wax, he cannot use the
  senses. He must use his mind.

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Descartes and the Existence of God

• Descartes wanted to prove the existence of God
  without having to depend on sensory evidence.
• Instead, Descartes relied on an intuitive chain
  of reasoning, starting with the notion that he
  knew he existed because he was a thing that
  thinks.
• It is greater perfection to know than to doubt
• Because man has doubt, and is therefore not
  completely perfect, there must be something more
  perfect than ones self.

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God as Perfection

• How do we have the ability to reason that there
  must be something more perfect than ones self?
• The idea of perfection must have been placed in
  humans by a being more perfect than man
• God possesses all that is infinite, eternal,
  immutable, omniscient, and perfect while man is
  imperfect and full of doubt
• God must exist because we have the ability to
  contemplate the idea that perfection and
  omniscience exists.