TODAY! TODAY! TODAY!

1. TODAY! TODAY! TODAY! *** YOU WILL: Work in groups! WE WILL: Review for next week’s exam! I WILL: Talk too much! ***

2. Skepticism • A “skeptic” is someone who claims that we do not, and can not know something. • But skepticism comes in many flavors.

3. “Global” vs “Local” Skepticism • “Global skepticism” questions our knowledge of everything. • A “global skeptic” claims that we cannot know anything at all.

4. “Global” vs “Local” Skepticism • “Local skepticism” questions our knowledge of some particular domain. • A “local skeptic” claims that we cannot know anything about, e.g., other minds.

5. “Methodological” vs “Substantive” Skepticism • A “methodological skeptic” uses skepticism as a tool. • A “substantive skeptic” actually endorses skepticism.

6. Exam #1-Review Descartes is not a substantive skeptic. He ultimately thinks that we can know a lot of things. What was Descartes’ reason for introducing his skeptical arguments?

7. Descartes’ 3-Step Method 1.Tear down all of his beliefs. (Doubt everything that can be doubted.) 2.Find sturdy foundations. (Find those beliefs which are certain and indubitable.) 3.Build back up. (Infer other beliefs from the "foundational" beliefs.)

8. Descartes’ Skepticism Descartes’ methodological skepticism helps him with steps 1 and 2 of his method: • Descartes' gives his skeptical arguments in order to achieve universal, hyperbolic doubt • The skeptical hypotheses he raises will provide a way to test whether or not a belief is certain and indubitable

9. The Dreaming Argument P1:I cannot rule out the possibility that I am merely dreaming that there is a cup on the table in front of me (because “there exist no certain marks by which the state of waking can ever be distinguished from sleep”). P2:If I cannot rule out this possibility, then I do not know that there is a cup on the table in front of me. (The “rule-out principle”.) -------------------------------------------------------------- C:Therefore, I do not know that there is a cup on the table in front of me.

10. The Evil Demon Argument P1:I cannot rule out the possibility that an evil demon is deceiving me into thinking that there is a cup on the table in front of me. P2:If I cannot rule out this possibility, then I do not know that there is a cup on the table in front of me. (The “rule-out principle”.) -------------------------------------------------------------- C:Therefore, I do not know that there is a cup on the table in front of me.

11. Exam #1-Review Consider the following objection to Descartes’ use of the Evil Demon argument: “Descartes’ discusses the Evil Demon in order to get himself to doubt everything. But he isn’t really doubting everything. Specifically, Descartes isn’t doubting that an evil demon exists. If he had doubted that the evil demon exists, his argument never would’ve gotten off the ground.” Describe what is wrong with this objection.

12. Exam #1-Review Descartes thinks that it is possiblethat an evil demon is deceiving me. Why does he think that this possibility is relevant to what I actually know?

13. “Rule-Out Principle” If you can't rule-out every possibility on which X is false, then you do not know that X is true.

16. Step 2-“Foundations” • Descartes wants to find indubitable beliefs to serve as his foundations. • But we might wonder whether this is going to be possible. • Is there any belief that can survive the Evil Demon?

17. Exam #1-Review In his Second Meditation, Descartes establishes one piece of certain knowledge--namely, the “Cogito”. (a) State the “Cogito”. (b) Explain why Descartes thinks that the “Cogito” withstands allskeptical doubt.

18. The Cogito “I am, I exist.”

19. “Dubitable” Beliefs A belief X is dubitable (doubt-able) if we can describe a possible situation where the following two things are both true: (i) I believe that X is the case. (ii) X is not the case.

20. The Cogito To deceive me about my own existence the Evil Demon would have to make the following things both true: (i) I believe that I exist (ii) I don’t exist.

21. Descartes’ Program Fasten your seat belts… After establishing the Cogito, Descartes: • Gives a proof that God exists • Argues that since God is all-good, he would not allow us to be massively deceived (by an Evil Demon, or under any other skeptical scenario).

22. Descartes’ 3-Step Method 1.Tear down all of his beliefs. (Doubt everything that can be doubted.) 2.Find sturdy foundations. (Find those beliefs which are certain and indubitable.) 3.Build back up. (Infer other beliefs from the "foundational" beliefs.)

23. Foundationalism • Descartes was a “foundationalist”. • Foundationalism is the view that our system of belief needs some kind of "foundation". According to foundationalists, in order for a belief to count as knowledge, it must be either: (i) A "foundational" belief, or (ii)Inferred from a "foundational" belief.

24. Descartes’ Foundationalism • And as we’ve seen, Descartes had a very strict view about which beliefs could count as “foundational”. • For Descartes, a foundational belief had to be indubitable (not doubt-able).

25. Alternatives to Descartes • Many philosophers have questioned Descartes strict foundationalism. • Some (e.g. Hume) have agreed with the structure of foundationalism, but have been more lenient about which beliefs can be foundational. • Others (e.g. Coherentists) have questioned the whole foundationalist picture.

26. Coherentism Coherentists reject the idea that our system of belief needs some kind of "foundation". According to coherentism: • Our system of beliefs should be structured such that all the beliefs "cohere". • In order for a belief to count as knowledge, it needs to play an appropriate role in a coherent system of beliefs.