1. Meditations: 3 & 4

2. Meditation III Clear and distinct ideas.
“I may now take as a general rule, that all that is very clearly and distinctly apprehended (conceived) is true” III:2

3. Meditation III
Descartes has established one unshakable truth. “I think there for I am.”
How does one use this to establish any other truth?
He has his Axiom, now how does one build a foundation of knowledge from this?

4. Meditation III Premises for doubt
Empirical knowledge: doubtable, prone to err.
A-priori knowledge: Hypothesized evil demon.
Next move…..remove a premise of doubt.

5. Meditation III
“But, that I may be able to remove it { the idea of an evil demon deceiving me} I must inquire whether there is a God, as soon as an opportunity of doing so shall present itself; and if I find that there is a God, I must examine likewise whether he can be a deceiver; for, without the knowledge of these two truths, I do not see that I can ever be certain of anything {beyond my first axiom}” III:4

6. Meditation III: 22-23
“There only remains, therefore, the idea of God, in which I must consider whether there is anything that cannot be supposed to originate with myself. By the name God, I understand a substance infinite, [eternal, immutable], independent, all-knowing, all-powerful, and by which I myself, and every other thing that exists, if any such there be, were created…..
(continued next page)

7. Meditation III: 22-23
…But these properties are so great and excellent, that the more attentively I consider them the less I feel persuaded that the idea I have of them owes its origin to myself alone. And thus it is absolutely necessary to conclude, from all that I have before said, that God exists.” III: 22

8. Meditation III: 22-23
“For though the idea of substance be in my mind owing to this, that I myself am a substance, I should not, however, have the idea of an infinite substance, seeing I am a finite being, unless it were given me by some substance in reality infinite.” III: 23

9. Meditation III: 24
“…for how could I know….that something is wanting in me, and that I am not wholly perfect, if I possessed no idea of a being more perfect than myself, by comparison of which I knew the deficiencies of my nature ?” III:24

10. Meditation III:38 Where does Descartes get his ‘idea’ of God?
Answer:. “And, in truth, it is not to be wondered at that God, at my creation, implanted this idea in me, that it might serve, as it were, from the mark of the workman impressed on his work.” Med. III:38

11. Ontological Argument: For God’s Existence.
The mere Idea of God, proves God’s existence.
“There is, then, so truly a being than which nothing greater can be conceived to exist, that it cannot even be conceived not to exist; and this being thou art, O Lord, our God.” St. Anselm

12. Ontological Argument
God is, by definition, the perfect Being conceivable.
A perfect Being conceivable cannot lack anything.
But if God did not exist, he would lack existence.

13. Ontological Argument
A Being that existed in reality would be greater than a Being that only existed in our minds.
Therefore, God must exist if He is the perfect Being conceivable.

14. Meditation III: summary
I have an idea of a perfect being: That idea could not have sprung from my own ideas. A finite mind could not comprehend an infinite idea (God)
It was implanted by God.

15. Meditation III: summary
God exists in reality; for if He only existed in my mind, He would not possess perfection. (I.e. Non-existence is an imperfection.)
A perfect being would not deceive (I.e. being a deceiver is an imperfection.) [Has a-priori back]

16. Meditation IV: Deception and Error
God does not deceive me. Yet in my life I have been deceived…How can this be?
God gave me sense(s) to understand, and a free will to choose to believe.
Every mental act of judgment, Descartes held,is the product of two distinct faculties; the understanding, which merely observes or perceives, and the will, which assents to the belief in question.

17. Errors happen when…
…by misusing my free will to assent on occasions for which my understanding does not have clear and distinct ideas.
For Descartes, error is virtually a moral failing, the willful exercise of my powers of believing in excess of my ability to perceive the truth.
(End)