1. 1 Paul Boghossian Fear of Knowledge: Against Relativism and Constructivism

2. 2

3. 3 §1 Who is Paul A. Boghossian? - Professor of Philosophy at New York University - Ph.D. at Princeton University - Works in philosophy of mind, language and music, as well as epistemology - Public intervention in the debate around the Sokal hoax: against “postmodernism” - His homepage: http://philosophy.fas.nyu.edu/object/paulboghossian http://philosophy.fas.nyu.edu/object/paulboghossian

4. 4 §2 What is Relativism? Relativism is not one doctrine but many x is relative to y

5. 5 §2 What is Relativism? Relativism is not one doctrine but many x is relative to y x = entities, facts, worlds: ontological relativism x = truth:semantic relativism x = moral value:moral relativism x = knowledge, justification:epistemic relativism

6. 6 §2 What is Relativism? Relativism is not one doctrine but many x is relative to y x = entities, facts, worlds: ontological relativism x = truth:semantic relativism x = moral value:moral relativism x = knowledge, justification:epistemic relativism y = the individual:Protagorean relativism y = culture:cultural relativism y = class, ethnic group, gender:standpoint relativism …

7. 7 Descriptive Relativism: y 1 and y 2 differ in their assess- ment of x – but no stance is taken on who is right: y 1, or y 2, or both, or none.

8. 8 Descriptive Relativism: y 1 and y 2 differ in their assess- ment of x – but no stance is taken on who is right: y 1, or y 2, or both, or none. Normative Relativism: The differing assessment of x in, or by, y 1 and y 2 are “equally valid”, and there is no y- independent assessment of different y.

9. 9 §3 What is Epistemic Relativism? - “Epistemic” refers to knowledge. - Knowledge is (on the traditional view): justified (or rationally formed) true belief. - We get epistemic relativism by treating the justification of beliefs as relative to different y. - This is less radical than some other forms of relativism: cf. ontological.

10. 10 A Quick Introduction to Chapter 5 …

11. 11 Galileo GalileiCardinal Roberto Bellarmine

12. 12 The geocentric universe of Ptolemy The heliocentric universe of Copernicus

13. 13 Galileo’s telescope

14. 14 - Bellarmine was arguing against the Copernican system with text passages from the Bible: “… the words ‘the sun also riseth and the sun goeth down, and hasteneth to the place where he ariseth, etc.’ were those of Solomon, who … spoke by divine inspiration …” (Bellarmine’s letter to P. A. Foscarini, 12 April 1615) - Galileo insisted on a sharp division between science and religion.

15. 15 Richard Rorty: Philosophy and the Mirror of Nature (1981): - Galileo: sharp division between science and religion. - We accept Galileo’s view, or “grid”, or “epistemic systems”. - Bellarmine had a different “grid”. - Bellarmine’s view is justifiable in terms of his system. - His epistemic system supports his view, our (and Galileo’s system) supports our view. - We can only argue for the superiority of our system using our system.

16. 16 - We can only argue for the superiority of our system using our system. - But a circular justification isn’t really a justification at all. - Hence we should accept that our initial belief in the absolute correctness of our own system is unjustified. - There are only relatively correct epistemic system – epistemic justification is relative to systems that are “equally valid”.

17. 17 Epistemic Relativism: A.Epistemic non-absolutism: There are no absolute facts about what belief a particular item of information justifies. B.Epistemic relationalism: “E justifies belief B” should be taken to express the proposition: According to the epistemic system C, that I (the speaker) accept, information E justifies belief B. C. Epistemic pluralism: There are many fundamentally different, genuinely alternative epistemic systems, but no facts by virtue of which one of these systems is more correct than any of the others.

18. 18 §4 Technical Terms in Boghossian’s Argument (a) Epistemic system: A system, or “grid”, of principles that specify under what conditions a belief is rational or justified.

19. 19 ( (b) Prima facie justification: Initial, “first pass”, justification before a wider variety of error possibilities have been considered.

20. 20 (c) Proposition vs. sentence: A sentence is a linguistic item in a specific language. A proposition is the meaning of a declarative sentence. Different sentences can express the same proposition. We grasp propositions. Many of our (mental) attitudes are attitudes towards propositions: “I believe that Boghossian is an American.”

21. 21 (d) Complete vs. incomplete propositions: A complete proposition is a proposition that is either true or false. An incomplete proposition is untrue but not false: it does not contain enough informational content for anyone to evaluate its truth value. E.g. “I am taller than …”

22. 22 ( (e) Valid vs. sound: An argument is said to have validity or to be valid if, and only if, it is the case that, if the premises of the argument are true, then the conclusion must be true. Validity is a conditional notion: what it says is that if the premises happen to be true, then the conclusion has to be true. Validity is not to be confused with soundness; a sound argument is not only valid, its premises are true as well.

23. 23 Compare: Snow is white. Grass is green. Blood is red. true premises true conclusion Invalid

24. 24 Compare: Snow is white. Cats are ships. Grass is green. Fido is a cat. Blood is red.Fido is a ship. true premisesfalse premises true conclusionfalse conclusion Invalidvalid

25. 25 Compare: Snow is white. Cats are ships. Dogs are animals. Grass is green. Fido is a cat. Fido is a dog. Blood is red.Fido is a ship. Fido is an animal. true premisesfalse premisestrue premises true conclusionfalse conclusiontrue conclusion Invalidvalidvalid & sound

26. 26 (f) Deduction, Induction (enumerative vs. hypothetical (= Inference to the Best Explanation)) Deductive argument: All humans are mortal. Socrates is human. Therefore: Socrates is mortal. Inductive argument (enumerative): All swans observed in past have been white. Therefore: All swans are white. Inductive argument (hypothetical): The best explanation of these footprints is that you were here. Therefore: You were here.

27. 27 Deduction vs. Induction 1. Only induction is ampliative. 2. Only valid deduction is necessarily truth preserving. 3. Only deduction is erosion-proof. 4. Only deductive validity is an all-or-nothing matter. Inductive arguments come in different degrees of strength.

28. 28 (g) Modus Ponens: A valid rule of inference: If (P implies Q), and P, then Q. (h) Conjunction Elimination: The rule: “From (P and Q), infer Q”.

29. 29 (i) Expressivism (esp. Gibbard’s norm expressivism): A philosophical theory which claims that the judgements of a certain domain (e.g. ethics) are expressions of the speakers’ attitudes towards (a system of) rules or norms. E.g. when Jones says: “Stealing is bad” … he is not saying that a certain kind of act (= stealing) has a certain kind of property (= badness). He is expressing his attitude of approval for a system of norms that forbids stealing.

30. 30 (j) Norm-circularity: The justification of a norm is “norm-circular” if it relies upon the very norm it is meant to justify.

31. 31 (k) Coherence: A set of beliefs coheres if they “fit together”. The minimal requirement is “logical consistency”: A set of beliefs is logically consistent if all its members can jointly be true. Stronger requirements are “inferential and explanatory connectedness”. Beliefs are inferentially connected if they follow from one another. Beliefs are connected by relations of explanation if they explain one another.

32. 32 (l) Blind entitlement: You are “blindly entitled” to a belief b if you are justified in holding b without having made any effort to justify b yourself.