Descartes’ Methodology : As stated in his Discourse of Method .

1. Descartes’ Methodology:As stated in his Discourse of Method. • The first was never to accept anything as true if I did not have evident knowledge of its truth; that is, carefully to avoid precipitate conclusions and preconceptions, and to include nothing more in my judgments than what presented itself to my mind so clearly and distinctly that I had no occasion to doubt it.

2. Descartes’ Methodology • The second, to divide each of the difficulties I examined into as many parts as possible and as may be required in order to resolve them better.

3. Descartes’ Methodology • The third, to direct my thoughts in an orderly manner, by beginning with the simplest and most easily known objects in order to ascend little by little, step by step, to knowledge of the most complex, and by supposing some order even among objects that have no natural order of precedence. • And the last, throughout to make enumerations so complete, and reviews so comprehensive, that I could be sure of leaving nothing out.

4. Descartes methodology: simply put.4 simple rules • 1. Accept as true only what is indubitable. • 2. Divide every question into manageable parts. • 3. Begin with the simplest issues and ascend to the more complex. • 4. Review frequently enough to retain the whole argument at once.

5. Descartes • For Descartes, ‘Reason’ was both the foundation and guide for pursuing truth. He was an active participant in the scientific revolution in both scientific method and in particular discoveries. Finally, and perhaps most importantly, Descartes reacted strongly against the Renaissance resurgence of ancient Greek skepticism. Thus, we find in Descartes' writings a relentless pursuit of absolute certainty.

6. Because of this….. • Rene’ Descartes is known as the ‘Father of Modern Philosophy.’

7. Hyperbolic Doubt • Descartes opens his Meditations by reiterating hisdesire to have only true beliefs, expressed as the first rule in the Discourse on the Method. Descartes proposes to systematically follow a process of doubt. The doubt is not a simply common sense one, though, as when I doubt whether black cats are harbingers of bad luck. Instead, his doubting process is a philosophical one, and sometimescalled 'hyperbolic' (or exaggerated) doubt, in which theissue is whether a class of knowledge can be in any way doubted. • The goal of this doubting process is to arrive at a list of beliefs that are certain and indubitably true. It thus may be viewed as a systematic doubting experiment.

8. Meditation 1:Systematic Doubt Senses can deceive: • Optical Illusions. • Psychotics/the insane (Brains infested by a black bile…) • Dreams that seem real. • May be no external world at all!! • Conclusion: Empirical knowledge cannot be trusted.

9. How Can Mathematics Deceive Us? • Evil Demon Hypothesis. • Evil Demon can distort our awareness of Primary Qualities (a-priori knowledge). • 2+2=5. • Conclusion: A-priori knowledge cannot be trusted.

10. After Meditation I and the beginning of II Descartes is left LOST… • Descartes is left with seeds for doubting his a priori knowledge and his a posteriori knowledge. • Both Empirical knowledge and Rational knowledge can be called into doubt….[Back to Readings: Meditation II]

11. So what is left? • Can I (Descartes) be certain of anything? • Answer is: “YES!” • Even if I am being deceived, then at least I am. • “I think; therefore, I am” • “I am thinking, I am a thinking thing.” • “Cogito Ergo Sum”(Latin) I am, I exist. • Known in philosophy as ‘The Cogito’.

12. End of Meditation II: Found!! • Now that I can be certain of this one thing,I will use this certainty to build again my knowledge anew. • Descartes has found the one thing he can be absolutely certain of. • This is the fulcrum point that he has searched for. • Descartes uses this for the cornerstone (foundation) of his knowledge. [Back to Readings: Med II #4]

13. Meditation II: 8 • “But what, then, am I? A thinking thing, it has been said. But what is a thinking thing? It is a thing that doubts, understands, [conceives’, affirms, denies, wills, refuses; that imagines also, and perceives.” • Mental Stuff ≠ Material Stuff. • Mental Stuff = Incorporeal • Material Stuff = Corporeal .

14. 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

15. 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?

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

17. 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

18. 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)

19. 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

20. 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

21. 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

22. 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

23. 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

24. 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.

25. 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.

26. 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.

27. 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] (Read pg. 455)

28. Meditation V • God has to exist. “…because I cannot conceive anything but God to whose essence existence necessarily pertains..” • Everything I conceive of clearly and distinctly is true. • God is true, he is not a deceiver. “Now that I know him, I have the means of acquiring a perfect knowledge of many things.” • The external world exists, I know it by the senses God has provided for me. (Emp. Back)

29. Cartesian Circle Some of Descartes’s friends and critics noticed a problem. How do I know “clear and distinct” ideas are true? Because a perfect God exists. How do I know God exists? Because I have a “clear and distinct” idea of God. One conclusion relies on the truth of the other. Both premises are also conclusions, a circular argument.

30. 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.

31. 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.

32. Meditation VI: Of the Existence of Material Things and the real distinction between the Soul and Body of Man. • Nature teaches me by the sensations of pain, hunger, thirst, etc. That I am not merely lodged in my body as a pilot in a ship, but that I am so closely united to it that I seem to compose with it one whole.

33. Meditation VI • For if that were not the case , when my body is hurt, I, the thinking thing, should not feel pain, but would perceive the wound just as the sailor perceives something damaged in this vessel. For all these sensations of hunger, thirst, pain, etc. are in truth just confused modes of thought produced by the apparent intermingling of mind and body.

34. Meditation VI • There is a great difference between mind and body, as body is by nature always divisible, and the mind is indivisible. • Notwithstanding the supreme goodness of God, the nature of man, composed of mind and body, can sometimes be a source of deception.

35. Meditation VI • But because the exigencies of action often oblige us to make up our minds before having leisure to examine matters carefully, we must confess that the life of man is frequently subject to error. We must in the end acknowledge the infirmity of our nature. [Back to Meditation VI ]

36. Wax example.Meditation II:11(In your reading-do not have to read in class) • Can undergo many changes yet we still ‘know’ that it is wax. How? • Answer: Our reason. Our intellect alone. Med. II: 16. • [Use water, ice, steam example] • Distinguishes Primary vs. Secondary qualities.

37. Primary and Secondary qualities • Much of Descartes argumentation rests on a distinction that, later in the history of philosophy, became known as that between primary and secondary qualities. Briefly, we look at an apple and perceive qualities of redness, sweet smell, roundness, and singularity.

38. Primary and Secondary qualities • Descartes recognized that the qualities of redness and sweet smell do not really belong to the apple. Instead these qualities exist only in the mind of an observer - as a product of the relation between the apple, my sense organs, and my mind - and are then illegitimately imposed onto the apple as it is in itself.

39. Primary and Secondary qualities • These have been traditionally called secondary qualities. By contrast, the qualities of roundness and singularity belong to the apple itself, and are not products of the relation to the observer's mind. These have been termed primary qualities. Secondary qualities arise from (what are assumed to be) objects of the senses, and primary qualities from objects of mathematics. • The following illustrates the connection:

40. Type: Objects Properties Secondary Objects of Sense hardness, heat, light, odour, colour, taste, sound Primary Objects of Mathematics quantity, shape, time, magnitude Primary Secondary Table .

41. God:Rationalism (Letter form Descartes to Mersenne on April 15, 1630) • “I would not allow myself in my physics to touch upon metaphysical questions, and particularly this one” that mathematical truths, which you call eternal, have been established by God and depend entirely on him, as does the rest of all creation.

42. God:Rationalism (cont.) • Do not worry at all, I beg of you, about assuring and publishing everywhere that it is God who has established these laws of nature, in the same way that a king establishes the laws of his realm. Now there is nothing at all that we are unable to comprehend, if our spirit inclines us to consider it, and all of these truths are innate in our spirit, in the same way that a king imprints his laws I the hearts of his subjects, if he has the power to do so.” (Descartes Secret Notebook: pg. 139)

43. In his letter of dedication in his Meditation on First Philosophy… • Descartes offered to contemporary theologians his proofs of the existence of God and the immortality of the human soul. This explicit concern for religious matters does not reflect any loss of interest in pursuing the goals of science.

44. In his letter of dedication in his Meditation on First Philosophy. • By sharply distinguishing the mind from body, Descartes hoped to preserve a distinct arena for the church while securing the freedom of scientists to develop mechanistic accounts of physical phenomena.

45. In his letter of dedication in his Meditation on First Philosophy. • In this way, he supposed it possible to satisfy the requirements of Christian doctrine, but discourage the interference of the church in scientific matters and promote further observation exploration of the material world.

46. Descartes’ Death • In 1649, Descartes moved to Stockholm at the request of Queen Christina of Sweden who employed him as a philosophy tutor. Christina scheduled the lectures at 5 A.M. The early hours and harsh climate took their toll on Descartes’s already weakened condition. He died shortly after in 1650. During his life, Descartes's fame rose to such an extent that (despite the theological controversies centering on him) many Catholics believed he would be a candidate for sainthood. As his body was transported from Sweden back to France, anxious relic collectors along the path removed pieces of his body. By the time his body reached France, it was considerably reduced in size. (End Descartes)

47. Descartes’ Skull