1. Knowledge Internalism and Externalism

2. What is Knowledge? Uncontroversial: Uncontroversial: Knowledge implies truth Knowledge implies truth I know that it ’ s Monday — > it ’ s MondayI know that it ’ s Monday — > it ’ s Monday Almost as uncontroversial: Almost as uncontroversial: Knowledge is a kind of belief Knowledge is a kind of belief I know that it ’ s Monday — > I believe that it ’ s MondayI know that it ’ s Monday — > I believe that it ’ s Monday

3. Plato Knowledge = true belief? Knowledge = true belief? But a belief might be true accidentally But a belief might be true accidentally Examples? Examples?

4. Plato’s Definition Knowledge = justified true belief, belief with an account Knowledge = justified true belief, belief with an account We must be able to give reasons We must be able to give reasons

5. Justified true belief Theaetetus. That is a distinction, Socrates, which I have heard made by some one else, but I had forgotten it. He said that true opinion, combined with reason, was knowledge, but that the opinion which had no reason was out of the sphere of knowledge; and that things of which there is no rational account are not knowable--such was the singular expression which he used--and that things which have a reason or explanation are knowable. Theaetetus. That is a distinction, Socrates, which I have heard made by some one else, but I had forgotten it. He said that true opinion, combined with reason, was knowledge, but that the opinion which had no reason was out of the sphere of knowledge; and that things of which there is no rational account are not knowable--such was the singular expression which he used--and that things which have a reason or explanation are knowable.

6. Foundationalism You can know something only if you can justify your belief, that is, explain why it must be true You can know something only if you can justify your belief, that is, explain why it must be true Your explanation must rely on other things you know Your explanation must rely on other things you know You must have explanations of them in terms of prior things you know You must have explanations of them in terms of prior things you know Regress stops: there must be a foundation of basic items ( “ the given ” ) known directly Regress stops: there must be a foundation of basic items ( “ the given ” ) known directly

7. Foundationalism The Given

8. Plato’s Dilemma for the Given If knowledge rests on a foundation of basic items, do we know them? If knowledge rests on a foundation of basic items, do we know them? If not, how can knowledge rest on the unknown? If not, how can knowledge rest on the unknown? If so, how can they be justified and yet basic? If so, how can they be justified and yet basic?

9. Plato’s Argument If knowledge is justified true belief, it has a foundation justifying everything else If knowledge is justified true belief, it has a foundation justifying everything else Items in the foundation are not justified Items in the foundation are not justified But they are known — more directly than anything else But they are known — more directly than anything else So, knowledge is not justified true belief So, knowledge is not justified true belief

10. Plato’s Argument Knowledge – > Justification Knowledge – > Justification The given is known The given is known But it ’ s not justified But it ’ s not justified The Given

11. Three Options Classical foundationalism: the given justify themselves Classical foundationalism: the given justify themselves Direct realism: sensations can justify knowledge without being knowledge Direct realism: sensations can justify knowledge without being knowledge Coherentism: knowledge has no foundation; there is no “ given, ” no level of ultimate justifiers Coherentism: knowledge has no foundation; there is no “ given, ” no level of ultimate justifiers

12. Classical Foundationalism The given is self-evident; it justifies itself The given is self-evident; it justifies itself The Given

13. Direct Realism The given = sensation The given = sensation The Given: Sense Experience

14. Coherentism Knowledge has no foundation Knowledge has no foundation Web of belief: Web of belief:

15. Internalist definition Knowledge = justified true belief Knowledge = justified true belief

16. Justification Beliefs may be justified: Beliefs may be justified: Inferentially: following from other justified beliefs Intrinsically: self- justifying, self- evident Direct realism: by sensation

17. Intrinsic justification Are there beliefs that justify themselves? Are there beliefs that justify themselves? If so, what are they? If so, what are they?

18. Self-evident truths? I think I think I am I am Everything that thinks exists Everything that thinks exists

19. Self-evident truths? That ’ s black That ’ s black That looks black That looks black That looks black to me now That looks black to me now I ’ m being appeared to blackly I ’ m being appeared to blackly It seems that I ’ m being appeared to blackly It seems that I ’ m being appeared to blackly

20. Self-evident truths? You ought to seek the good You ought to seek the good You ought to avoid evil You ought to avoid evil

21. Inference A belief can be justified by being inferred from other justified beliefs A belief can be justified by being inferred from other justified beliefs What is a good inference? What is a good inference? What is an argument? What is an argument?

22. Transparency Justification is internal: following from other justified beliefs Justification is internal: following from other justified beliefs So, justification is transparent to the knower: if you are justified, you [can] know it So, justification is transparent to the knower: if you are justified, you [can] know it Chisholm: “If a person S is internally justified in believing a certain thing, then this may be something he can know just by reflecting upon his own state of mind.” Chisholm: “If a person S is internally justified in believing a certain thing, then this may be something he can know just by reflecting upon his own state of mind.”

23. KK Thesis KK thesis: if you know, you [can] know that you know KK thesis: if you know, you [can] know that you know I am I am I know I am I know I am I know I know I am I know I know I am I know I know I know I am.... I know I know I know I am....

24. Internalism How to distinguish knowledge from other mental states (belief, desire, hope, wonder, doubt, etc.)? How to distinguish knowledge from other mental states (belief, desire, hope, wonder, doubt, etc.)? I know the Longhorns will winI know the Longhorns will win I think the Longhorns will winI think the Longhorns will win I want the Longhorns to winI want the Longhorns to win I hope the Longhorns winI hope the Longhorns win I wonder whether the Longhorns will winI wonder whether the Longhorns will win I doubt whether the Longhorns will winI doubt whether the Longhorns will win

25. Internalism Internalism: distinguish knowledge in terms of truth and things inside the mind: Internalism: distinguish knowledge in terms of truth and things inside the mind: the character of the state itself andthe character of the state itself and Its relations to other mental statesIts relations to other mental states

26. Problems with internalism

27. Attacking internalism Knowledge = justified true belief? Knowledge = justified true belief? Too narrow (necessity): knowledge that isn ’ t justified? Too narrow (necessity): knowledge that isn ’ t justified? Too broad (sufficiency): justified true belief that isn ’ t knowledge? Too broad (sufficiency): justified true belief that isn ’ t knowledge? Knowledge Justified true belief Too narrow Too broad

28. Too Narrow? Internalism: knowledge = justified true belief Internalism: knowledge = justified true belief Is justification really necessary? Is justification really necessary? Can you know something without being able to justify it? Can you know something without being able to justify it?

29. Pop Quiz What ’ s the capital of Egypt? What ’ s the capital of Egypt? State the numerical value of π to two decimal places. State the numerical value of π to two decimal places. Who invented the penicillin? Who invented the penicillin? Who is Lisa Simpson ’ s teacher? Who is Lisa Simpson ’ s teacher?

30. Is Justification Necessary? Can you justify any of those answers? Can you justify any of those answers? So, who needs justification? So, who needs justification?

31. The Gettier Problem Too broad Too broad Justification is NOT enough! Justification is NOT enough! We can be We can be JustifiedJustified RightRight But right by accidentBut right by accident

32. The Gettier Problem Hassan and Neder both apply for a job Hassan and Neder both apply for a job Hassan has strong evidence that Neder will get the job Hassan has strong evidence that Neder will get the job Hassan also has strong evidence that Neder has 10 coins in his pocket Hassan also has strong evidence that Neder has 10 coins in his pocket

33. The Gettier Problem Hassan concludes Hassan concludes And is justified in concluding that And is justified in concluding that The man who will get the job has 10 coins in his pocket The man who will get the job has 10 coins in his pocket

34. The Gettier Problem But in fact Hassan will get the job But in fact Hassan will get the job And Hassan has 10 coins in his pocket And Hassan has 10 coins in his pocket So, Hassan is right! So, Hassan is right! But not in the way he thinks But not in the way he thinks

35. The Gettier Problem Hassan believes that the man who will get the job has 10 coins in his pocket Hassan believes that the man who will get the job has 10 coins in his pocket He ’ s right He ’ s right He justified He justified But does he know? But does he know?

36. Murderhorn Hassan believes he ’ ll plant a flag on the top Hassan believes he ’ ll plant a flag on the top He has justification (PowerSauce bars) He has justification (PowerSauce bars) He ’ s right — but not for the reason he thinks He ’ s right — but not for the reason he thinks Does he know? Does he know?

37. A Possible Solution Hassan infers the truth from something false (that Neder will get the job) Hassan infers the truth from something false (that Neder will get the job) Inferential justification: following from other justified beliefs Inferential justification: following from other justified beliefs Maybe we should say: following from other things known Maybe we should say: following from other things known Following only from true information Following only from true information

38. Loss of transparency But then we can ’ t judge justification internally But then we can ’ t judge justification internally We lose transparency We lose transparency We can ’ t tell when we ’ re justified We can ’ t tell when we ’ re justified We can ’ t tell whether we know We can ’ t tell whether we know

39. Too Narrow? Suppose we don ’ t know anything based on even a bit of false information Suppose we don ’ t know anything based on even a bit of false information Won ’ t this exclude much of our knowledge? Won ’ t this exclude much of our knowledge?

40. Fake Barn County Hamdy sees what appears to be a barn in the field Hamdy sees what appears to be a barn in the field He infers that there ’ s a barn in the field He infers that there ’ s a barn in the field He ’ s right He ’ s right He has a belief, it ’ s justified, and it ’ s true — and, everything he bases it on is true and known He has a belief, it ’ s justified, and it ’ s true — and, everything he bases it on is true and known

41. Fake Barn County But, unbeknownst to Hamdy, most barns in this area are fake But, unbeknownst to Hamdy, most barns in this area are fake Does he know that there ’ s a barn? Does he know that there ’ s a barn?

42. Externalism

43. Externalism To distinguish knowledge from other mental states, reality To distinguish knowledge from other mental states, reality We must invoke relations between mental states and the world We must invoke relations between mental states and the world Knowledge = true belief formed by a reliable process of belief formation Knowledge = true belief formed by a reliable process of belief formation Not necessarily transparent to knower Not necessarily transparent to knower

44. Externalism Replace internal, transparent justification with something external, opaque, linked to the world Replace internal, transparent justification with something external, opaque, linked to the world Knowledge = true belief produced by a reliable process Knowledge = true belief produced by a reliable process

45. Reliable processes What is a reliable process? What is a reliable process? It produces mostly true beliefs It produces mostly true beliefs When used normally, When used normally, In normal situations In normal situations

46. Indian Externalism Two Hindu darshanas, Nyaya (logic) and Vaisesika (particularism), merged around 1000 in the work of Udayana Two Hindu darshanas, Nyaya (logic) and Vaisesika (particularism), merged around 1000 in the work of Udayana Proponents are Nyayayikas Proponents are Nyayayikas Earliest work: Nyaya-sutra, by Gautama (200) Earliest work: Nyaya-sutra, by Gautama (200)

47. Pramanas Pramana = means (source) of knowledge Pramana = means (source) of knowledge PerceptionPerception InferenceInference AnalogyAnalogy Reliable testimonyReliable testimony Knowledge is true belief produced by a reliable means of knowledge (pramana) Knowledge is true belief produced by a reliable means of knowledge (pramana)

48. Perception Perception is synthetic, veridical, and definite Perception is synthetic, veridical, and definite Sutra 4: Perception is the cognition resulting from sense-object contact [and which is] 'not due to words', 'invariably related' [to the object] and is 'of a definite character'. Sutra 4: Perception is the cognition resulting from sense-object contact [and which is] 'not due to words', 'invariably related' [to the object] and is 'of a definite character'.

49. Perception Perception is a reliable process Perception is a reliable process We perceive most things accurately We perceive most things accurately When using our sense organs normally When using our sense organs normally In normal situations In normal situations So, accurate perception — > knowledge So, accurate perception — > knowledge

50. Perceptual mistakes We don ’ t perceive everything accurately We don ’ t perceive everything accurately Illusions Distorting glasses and mirrors Strange lighting But those cases are anomalous But those cases are anomalous

51. Analogy We use analogy, especially in knowing language We use analogy, especially in knowing language Sutra 6: Comparison is the instrument of the valid knowledge of an object derived through its similarity with another well-known object. Sutra 6: Comparison is the instrument of the valid knowledge of an object derived through its similarity with another well-known object.

52. Testimony Sutra 7: Verbal testimony is the communication from a 'trustworthy person'. Bhasya: A trustworthy person is the speaker who has the direct knowledge of an object and is motivated by the desire of communicating the object as directly known by him. Sutra 7: Verbal testimony is the communication from a 'trustworthy person'. Bhasya: A trustworthy person is the speaker who has the direct knowledge of an object and is motivated by the desire of communicating the object as directly known by him.

53. Testimony Testimony is a reliable process? Testimony is a reliable process? What we learn through testimony is mostly accurate What we learn through testimony is mostly accurate From normal witnesses From normal witnesses In normal situations In normal situations Testimony — > knowledge Testimony — > knowledge

54. Inference Inference is also a reliable process Inference is also a reliable process We draw conclusions accurately We draw conclusions accurately When reasoning normally When reasoning normally In normal situations In normal situations So, inference — > knowledge So, inference — > knowledge

55. Inference Sutra 5: Next [is discussed] inference, which is preceded by it [i.e., by perception], and is of three kinds, namely, inferring the effect (i.e. having the antecedent as the probans), inferring the cause (i.e. having the consequent as the probans) and inferring the rule (i.e. where the general law is ascertained by general observation). Sutra 5: Next [is discussed] inference, which is preceded by it [i.e., by perception], and is of three kinds, namely, inferring the effect (i.e. having the antecedent as the probans), inferring the cause (i.e. having the consequent as the probans) and inferring the rule (i.e. where the general law is ascertained by general observation).

56. Kinds of inference Inferring the effect Inferring the effect We know cause (e.g., lightning)We know cause (e.g., lightning) We expect effect (e.g., thunder)We expect effect (e.g., thunder) Inferring the cause Inferring the cause We know effect (e.g., thunder)We know effect (e.g., thunder) We infer the cause (e.g., lightning)We infer the cause (e.g., lightning) Inferring the rule Inferring the rule We know instances and generalize (e.g., lightning causes thunder)We know instances and generalize (e.g., lightning causes thunder)

57. Deductive inference An inference: An inference: Premises Conclusion An inference is deductively valid if the truth of the premises guarantees the truth of the conclusion An inference is deductively valid if the truth of the premises guarantees the truth of the conclusion

58. Deductive inference Examples: Examples: All men are mortalAll men are mortal Socrates is a manSocrates is a man Socrates is mortalSocrates is mortal Aristotle tutored AlexanderAristotle tutored Alexander Aristotle tutored someoneAristotle tutored someone

59. Inductive inference An inference is inductively strong if the truth of the premises makes the truth of the conclusion probable An inference is inductively strong if the truth of the premises makes the truth of the conclusion probable Example: Example: All ravens we ’ ve observed are black All ravens are black

60. Common sense inference An inference is defeasibly valid if the truth of the premises makes it reasonable to accept the conclusion, in the absence of further information An inference is defeasibly valid if the truth of the premises makes it reasonable to accept the conclusion, in the absence of further information

61. Common sense inference Examples: Examples: Birds fly Tweety is a bird Tweety flies Birds fly Penguins don ’ t fly Penguins are birds Tweety is a penguin Tweety doesn ’ t fly

62. Anything else? Perception + inference Perception + inference Everyone agrees these are reliable sources of knowledge Everyone agrees these are reliable sources of knowledge But are there others that don ’ t reduce to them? But are there others that don ’ t reduce to them?

63. Memory Memory is a reliable process? Memory is a reliable process? We generally remember accurately We generally remember accurately When our memories When our memories And the situation are normal And the situation are normal Memory — > knowledge Memory — > knowledge

64. Gettier problem Reasoning with false premises — that Neder will get the job — isn ’ t reliable Reasoning with false premises — that Neder will get the job — isn ’ t reliable Hassan process of belief formation isn’t reliable Hassan process of belief formation isn’t reliable So, Hassan doesn’t know So, Hassan doesn’t know

65. Fake barns Perception is generally reliable Perception is generally reliable So, if Hamdy sees a barn in the field, he knows there ’ s a barn in the field So, if Hamdy sees a barn in the field, he knows there ’ s a barn in the field But in Fake Barn County, that perception is unreliable But in Fake Barn County, that perception is unreliable So, Hamdy doesn ’ t know So, Hamdy doesn ’ t know

66. Context How do we select the appropriate context? How do we select the appropriate context? In this field, barns are real In this field, barns are real In this county, barns are generally fake In this county, barns are generally fake In this part of the state, barns are generally real In this part of the state, barns are generally real In this state, barns are generally fake.... In this state, barns are generally fake....