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Indian Theories of Knowledge
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What is Knowledge? Uncontroversially: Knowledge implies truth –I know that it’s Monday —> it’s Monday Almost as uncontroversially: Knowledge is a kind of belief –I know that it’s Monday —> I believe that it’s Monday
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Warrant Knowledge = Truth + Belief + __________ Call the property that has to be added to true belief to get knowledge warrant By definition, Knowledge = warranted true belief
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What is Warrant? Knowledge = warranted true belief Belief: Internal—the kind of mental state knowledge is Truth: External—connects that mental state to the world Is warrant internal or external?
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Internalism Warrant is internal We already know what kind of mental state knowledge is So, warrant must be a relation to other mental states Belief Truth Warrant
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Internalism How to distinguish knowledge from other mental states (belief, desire, hope, wonder, doubt, etc.)? –I know the Longhorns will win –I think the Longhorns will win –I want the Longhorns to win –I hope the Longhorns win –I wonder whether the Longhorns will win –I doubt whether the Longhorns will win
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Internalism Internalism: distinguish knowledge in terms of truth and things inside the mind: –the character of the state itself and –Its relations to other mental states
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Externalism Warrant is external We already know that the belief must be true; it matches the world now So, warrant must be a matter of how that belief arose Belief Truth Warrant
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Externalism To distinguish knowledge from other mental states, We must invoke relations between mental states and the world Knowledge = true belief formed by a reliable process of belief formation Not necessarily transparent to knower
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Externalism Replace internal, transparent justification with something external, opaque, linked to the world Knowledge = true belief produced by a reliable process
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Reliable Processes What is a reliable process? It produces mostly true beliefs When used normally, In normal situations
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Indian Externalism Two Hindu darshanas, Nyaya (logic) and Vaisesika (particularism), merged around 1000 in the work of Udayana Proponents are Nyayayikas Earliest work: Nyaya-sutra, by Gautama (200)
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Pramanas Pramana = means (source) of knowledge –Perception –Inference –Analogy –Reliable testimony Knowledge is true belief produced by a reliable means of knowledge (pramana)
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Perception 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'.
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Perception A genuine perception must be veridical Perceptual awareness arises from sense- organ connection with the object known It is not mediated by language A vaguely perceived object is not known; the vaguely perceiving awareness is not a genuine perception We know only what is definite
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Analogy 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..
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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
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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)
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Kinds of Inference Inferring the effect –We know cause (e.g., lightning) –We expect effect (e.g., thunder) Inferring the cause –We know effect (e.g., thunder) –We infer the cause (e.g., lightning) Inferring the rule –We know instances and generalize (e.g., lightning causes thunder)
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Perception Perception is a reliable process We perceive most things accurately When using our sense organs normally In normal situations So, accurate perception —> knowledge
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Perceptual Mistakes We don’t perceive everything accurately –Illusions –Distorting glasses and mirrors –Strange lighting But those cases are anomalous
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Inference Inference is also a reliable process We draw conclusions accurately When reasoning normally In normal situations So, inference —> knowledge
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Deductive Inference An inference: –Premises –Conclusion An inference is deductively valid if the truth of the premises guarantees the truth of the conclusion
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Deductive Inference Examples: –All men are mortal –Socrates is a man –Socrates is mortal –Aristotle tutored Alexander –Aristotle tutored someone
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Inductive Inference An inference is inductively strong if the truth of the premises makes the truth of the conclusion probable Example: –All ravens we’ve observed are black –All ravens are black
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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
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Common Sense Inference 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
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Anything Else? Perception + inference Everyone agrees these are reliable sources of knowledge But are there others that don’t reduce to them?
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Memory Memory is a reliable process? We generally remember accurately When our memories And the situation are normal Memory —> knowledge
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Testimony Testimony is a reliable process? What we learn through testimony is mostly accurate from normal witnesses in normal situations Testimony —> knowledge
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Gettier Problem Reasoning with false premises— that Ned will get the job— isn’t reliable Homer’s process of belief formation isn’t reliable So, Homer doesn’t know
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Fake Barns Perception is generally reliable So, if Homer sees a barn in the field, he knows there’s a barn in the field But in Fake Barn Country, that perception is unreliable So, Homer doesn’t know
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Attacking Externalism Knowledge = justified true belief? Too narrow (necessity, false negatives): knowledge that isn’t reliably produced? Too broad (sufficiency, false positives): reliably produced true belief that isn’t knowledge? Knowledge Reliably produced true belief Too narrow Too broad
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Context How do we select the appropriate context? In this field, barns are real In this county, barns are generally fake In this part of the state, barns are generally real In this state, barns are generally fake...
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Nagarjuna (c. 1000)
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Nagarjuna Mahayana Buddhist, 14th Indian Zen patriarch Founder of Madhyamika Buddhism Destroy theorizing Leave ordinary life alone: “For we do not speak without accepting, for practical purposes, the work-a-day world.”
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Attack on Externalism I know something because it arises from a reliable source of knowledge But how do I know that source of knowledge is reliable? Need a source of sources, etc.— infinite regress
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Nagarjuna’s Regress Argument “And if, for you, there is a source [of knowledge] of each and every object of proof, Then tell how, in turn, for you there is proof of those sources. If by other sources [of knowledge] there would be the proof of a source-- that would be an ‘infinite regress’; in that case neither a beginning, middle, or and end is proved.”
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Source of Sources? Sources of knowledge: perception, inference Knowledge is justified only if we know we’re using the appropriate source What could be source of knowledge for that?
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Nagarjuna: Quietism If knowledge is impossible, how can we know the truth of skepticism? Isn’t skepticism unreliable or unjustified? “If I would make any proposition whatever, then by that I would have a logical error; But I do not make a proposition, therefore I am not in error.”
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Nyaya Response We don’t need a source for sources Sources of knowledge and objects of knowledge support each other Sutra 16: Just as the 'measuring instrument' (which usually has the status of a source) can be an object of knowledge as well (i.e. when its own accuracy is subject to investigation)
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Scales Analogy: scales How do we test the reliability of a scale?
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Scales
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Analogy: scales How do we test the reliability of a scale? We compare weights it gives for objects with known weights by other scales. We don’t need a “scale of scales.”
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Nyaya Coherentism No foundation, no given One thing may be justifier or justified, depending on circumstances Epistemic role depends on context
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Luminosity Sutra 19:... these (i.e. perception etc.) are apprehended in the same way as the light of a lamp Light can be both means of seeing and the thing seen
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Gangesa (c. 1350) Local doubt (e.g., eyes, scale): we doubt when something anomalous happens, and resolve as in the Nyaya-sutra Global doubt: we have no reason to entertain; makes no sense to say everything is anomaly
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Pragmatic Inconsistency “Thus it has been said (by Udayana): "That is doubted concerning which as doubted there occurs no contradiction with the doubter's action." For it is not possible at once to resort regularly to fire and the like for smoke and the like and to doubt that fire causes it (it would be meaningless behavior). This is how we should understand Udayana's saying.... It is the doubter's own behavior that proves the lie to the doubt, i.e., that blocks it.”
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Smoke on the Mountain
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