Rationalism of Descartes

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Rationalism of Descartes

• Dr. Amir Salehi

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Overview

• Descartes argument in support of rationalism
• Notion of innate ideas
• Problem of Skepticism in epistemology
• Cartesian Project
• Cartesian approach (method) in response to
  skepticism
• Descartes systematic doubt and its purpose
• Results of Cartesian epistemology
• Dualism Mind-Body Problem
• Descartes argument in support of Dualism
• Descartes arguments in support of God
• Descartes response to his systematic doubt (the
  existence of material world)
• Quiz

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Descartes argument in support of rationalism

• P 1 Two objects are different if experience can
  show that the qualities of objects are different
  (empiricist view)
• P 2 Experience shows that liquid wax and solid
  wax have different qualities
• C Liquid wax and solid wax are different
  objects

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Notion of innate ideas

• In accordance with the rationalist view, there
  are representations or ideas in the mind that do
  not have empirical origins (a priori
  representations).
• Rationalists consider the possibility that humans
  are born with these types of ideas.

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Problem of Skepticism in epistemology

• Knowledge is not possible due to the fact that
  all knowledge remains uncertain.
• Aspects of uncertainty in epistemology
• No knowledge is definite
• No knowledge can be justified

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Cartesian Project

• The purpose of Cartesian epistemology is to
  develop a new philosophy (a new system of
  thinking for philosophizing as such).
• This new system of thought should be able to
  achieve the certainty of knowledge / to withstand
  the tests and challenges of skepticism.

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Cartesian approach (method) in response to
skepticism

• Descartes Geometry provides an ideal model for
  developing a new system of thinking in
  Philosophy.
• Authorities should have no place in a
  philosophical inquiry as they have no place in
  Geometry.
• Philosophical issues should be discussed as
  carefully and systematically as issues are
  discussed and proven in geometry.
• Deductive reasoning should be the preferred
  method of reasoning as it is in Geometry.
• Any deductive system such as Geometry is based on
  self-evident axioms therefore a similar
  foundation is required for the new system of
  thinking in Philosophy as well.

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Descartes systematic doubt and its purpose

• Descartes systematic method of doubt can be
  understood as a strategy of thinking to overcome
  skepticism (to change the uncertainty to
  certainty by beginning with skepticism).
• In accordance with this method, there are three
  grounds for doubt
• Hallucinations
• Dreams
• Illusions

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Cartesian systematic method of doubt

• Objects of experience can be illusion, dream or
  hallucination therefore their true existence can
  be doubted.
• Descartes As skepticism suggests, everything
  should be and can be the subject of doubt, but
  there is one thing that cannot be doubted, and
  that is the doubting process.
• Descartes Since doubting cannot be doubted, it
  follows that doubting exists, but what is the
  nature of doubting?
• Descartes Doubting is a mind activity therefore
  there is a thinking mind that makes doubting
  possible, and if I am the person who thinks by
  doubting, then it follows that I exist ( my doubt
  proves my existence) / Cogito ergo sum or I
  think, therefore I am.

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Dualism Mind-Body Problem

• Dualism is the metaphysical view that suggests
  that Mind Body (Immaterial Material entities)
  are two distinct entities, or ontologically
  separate (exist independently from each other).
• Mind - Body Problem If Mind and Body have
  different natures ( they represent distinct types
  of being), then how can they interact ( why do
  and how are Mind and Body capable of
  communicating with each other)?

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Descartes' argument in support of Dualism

• P1 Two entities are the same entities if they
  share all and the same properties (Principle of
  Identity)
• P2 Material Immaterial entities do not
  share common properties
• C Material Immaterial entities (Mind
  Body) are not the same type of entities
  (ontologically different, therefore Dualism).

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Descartes' arguments in support of God

• Descartes defines the notion of God as a perfect
  being.
• First argument What is the origin or the source
  of the idea of Perfection (perfect being)?
• Answer The existence of God.
• Second argument
• P1 God is defined as a perfect being
• P2 Nothing is perfect unless it exists
• C God exists

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Descartes response to his systematic doubt

• The existence of Mind cannot be doubted due to
  Cogitio statement therefore the immaterial mind
  exists.
• The existence of a material world cannot be
  doubted either due to the existence of God.

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Quiz

• What is the argument of Descartes in support of
  rationalism?
• What is the purpose of Cartesian epistemology?
• What is the Cartesian method for achieving the
  above goal?
• Describe and discuss the origin of the Cogito
  Statement.
• What is the purpose of Cogito Statement?
• What is Dualism and the problem associated with
  this view?
• What is the argument of Descartes in support of
  Dualism?
• What are the arguments of Descartes in support of
  God?
• Describe and discuss the systematic method of
  doubt.