Lecture 19 Notes

Meditation 5

I.    A Word of Background
II.   First Proof of God's Existence
III.  The Argument of Meditation 5
IV.   Objections
V.   The Cartesian Circle

I.    A Word of Background

• Remember the context of the Meditations: ages of science and reform. Descartes’s is an age of reform in which Catholicism perceived to be intellectually embattled.

• Descartes presents Meditations to Theology Faculty in Paris in presentation epistle, says that wants to demonstrate Catholic doctrine even to unbelievers includes most fundamental doctrine - existence of God

• Aquinas had argued that the existence of God can be proven.  He offered five of his own proofs which proceeded from observed facts about the world: e.g. it is ordered, things change, have purpose.  Descartes thought that all of these premises were dubitable.

• Cartesian proofs of God’s existence must begin elsewhere.

II.   First Proof of God's Existence

• The argument of Meditation 5 is the second "proof" of God’s existence.  In Meditation 3, Descartes finds in himself the idea of God.  This raises a question: Where did this idea come from?  What is best explanation for having the idea?  Descartes argues that the best explanation for his having the idea is that there is a being corresponding to it.
  
• The core idea of the argument in Meditation 3 is this: the idea of God is so real that it can have no other cause than God.  Let’s look briefly at the argument.  Doing so will help us understand the argument of Meditation 5.
  
• To see how argument goes, look at a couple of questions:
  

1. Consider a character on "Melrose Place": Amanda.  Now consider the producer of "Melrose Place": Aaron Spelling.  Can Amanda be the cause of Aaron Spelling?  he of her?  The answer seems to be "no", and it is grounded on Principle A: A fictional character can’t cause a non-fictional one.  To see why Principle A is true, let’s ask another question:
   
2. There is a device running through a memorable episode of "Party of Five".  Julia’s boyfriend is writing story optimistically based on them.  But he is fictional TV character and the characters in his story are fictional too.  Could they cause him?  Could he cause them?  This gives us Principle B: A cause must have at least as much reality as its effect: "there must at least be as much reality in the efficient and total cause as in its effect" (Meditation 3, Paragraph 14).
   

• Principle B should seem plausible, it explains Principle A.  But the argument for Principle B ignores an important possibility.  Consider a criminal trial in which a child is the only witness.  Imagine that the child recounts the crime in great and vivid detail.  Imagine further that the child is moved to strong emotion by his own testimony and that the jury accepts testimony.  Why does it do so?  Consider Principle C: some ideas have so much reality that a person having them could not be the cause of those ideas.
  
• Principle B + Principle C = Principle D (D for 'Descartes'): The cause of an idea must have at least as much formal reality as the idea has objective reality.
  
• Put together the idea of an infinite God, the finitude of Descartes and Principle D.  It follows that there is a God who causes this idea like "the mark of a workman impressed on his work" (Mediation 3, Paragraph 38).  Note how this argument depends on clarity and distinctness.
  

III.   The Argument of Meditation 5

A.   The Veracity of Clear and Distinct Perception

• Descartes has argued previously that everything he perceives "clearly and distinctly" by the "natural light" is true.
  

1. Some truths seem to have an obviousness about them. They have what philosophers have since called "self-evidence", e.g. 2+2=4, "every bachelor is unmarried", "squares have 4 sides", and "parallel lines never meet".  These are things we perceive clearly and distinctly to be true. Descartes thinks that everything that has this obviousness about it must be true.
   
2. "Natural light" is by Descartes’s time a dead metaphor.  It began with theological provenance: in Augustine, light is Christ's provenance.  The metaphor is therefore ironic
   

B.   Perception of God's Nature is Clear and Distinct

• Descartes understands clearly and distinctly that: it belongs to nature of the number 4 to be a square.  It belongs to nature of the number 5 to be the sum of two primes.  It belongs to nature of triangle to have three sides.  To understand the nature of these things is to see a property that is part of that nature.
  
• Descartes understands just as clearly and distinctly that: it belongs to the nature of God to exist.  To understand the nature of God is to see that existence is part of God’s nature.
  

C.   (A) + (B), Descartes thinks, Demonstrates that God Exists

1. Everything Descartes perceives clearly and distinctly is true.
2. Descartes perceives clearly and distinctly that existence belongs to the nature of God.
3. Therefore, "although all the conclusions of the preceding Meditations were false, the existence of God would pass with me for a truth at least as certain as I ever judged any truth of mathematics to be". (Meditation 5, Paragraph 7)

D.   Ontological Argument

• "Ontology is study of being, existence".
  
• This argument seems to depend on the nature of existence.
  
• It is a very old form of argument for God’s existence that has continuing fascination: even if it does work, it shouldn’t.
  

IV.   Objections

A.   Is Existence Really a Perfection?

• Is it better to exist than not to exist?
  
• Is existence really a property like omnipotence, omniscience, omnibenevolence?
  

B.   Do We Really Conceive of God Clearly and Distinctly?

• Can we have such a grasp of an infinite nature?
• Perhaps we could grasp divine nature only if God is not as Descartes alleges.
  

V.   The Cartesian Circle

A.   Statement of Premise 1

• "The Cartesian Circle", the most serious and famous objection to Descartes, begins with a close examination of Premise 1 (III.A. above): everything perceived clearly and distinctly is true.
• But how do we know this?  Can’t things so perceived still be false?
  

B.   How Does Descartes Justify Premise 1?

• Descartes can't say that this premise is perceived clearly and distinctly on pain of circularity.  Consider what he says:

D.   The Trouble

• So, the argument that premise (1) is true depends upon knowing that God exists.
  
• But we know God exists by relying on premise (1), which also plays a role in argument for God’s existence in Meditation III.
  
• Therefore, Descartes has argued in a circle.