gettier cases themes in ethics and epistemology shane ryan [email protected] 11/11/13

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Gettier Cases Themes in Ethics and Epistemology Shane Ryan [email protected] 11/11/13

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Gettier Cases

Themes in Ethics and Epistemology

Shane [email protected]

11/11/13

Issues

Preliminaries: What is epistemology? The JTB account of knowledge

Gettier cases: Having justified true beliefs but lacking knowledge

Structure

1. What is the scope of epistemology?

2. What is the methodology of epistemology?

3. The JTB account of knowledge

4. Gettier cases

5. Conclusion

1. What is the scope of epistemology?

Kvanvig (2005): epistemology is the study of purely theoretical cognitive success. We focus on the intrinsic features of cognition, and abstract from practical, political, social, religious and moral consequences of cognition.

Epistemic goals include truth, knowledge, justification, understanding, wisdom and rationality.

The focus of epistemology, however, is on the study of knowledge.

1. What is the scope of epistemology?

Different kinds of knowledge

Propositional knowledge: knowledge-that

“A proposition is what is asserted by a sentence which

says that something is the case”. (Pritchard, 2006: 3). Propositions may be true or false.

Examples:

“All bachelors are unmarried men.” “Paris is the capital of France.” “Democracy has become a sham.”

1. What is the scope of epistemology?Different kinds of knowledge

Ability knowledge: know-how

Knowing how to do something. Example: Knowing how to ride a bike

Propositional knowledge and ability knowledge differ in that I may know how to ride a bike but that does not imply that I know a set of propositions about how to ride a bike.

My knowledge how to ride a bike is demonstrated by me riding a bike.

Epistemology has been more concerned with propositional knowledge

1. What is the scope of epistemology?

Another Useful Distinction

C. A. J. Coady (1992, 3) distinguishes what he calls positive epistemology from negative epistemology. The former investigates the structure of knowledge or the body of beliefs that can reasonably be thought of as knowledge, and leaves sceptical worries aside; while the latter is concerned with the theoretical problems raised by scepticism.

Greco (2010, 5), similarly, distinguishes what he calls “the project of explanation”, which seeks to explain “what knowledge is and how knowledge is possible”, and “the project of vindication”, which is the project “of showing that we have knowledge”.

2. What is the methodology of epistemology?Defining knowledge

How can we define knowledge? Approach I: Look at paradigm cases of

knowledge and identify what's common. Problem: But this just seems to assume that we

already have a criteria for knowledge that is right, otherwise how could we identify such cases of knowledge?

2. What is the methodology of epistemology?Defining knowledge

Approach II: Identify the criteria for knowledge. But this faces an analogous problem. I am only

able to do so if I can already identify instances of knowledge.

This is the problem of the criterion.

2. What is the methodology of epistemology?

Response

We should either, (i) assume that we know or through philosophical reflection alone can identify the criteria (methodism),

or

(ii) we should assume that we can identify particular cases of knowledge (particularism)

2. What is the methodology of epistemology?

(i) is mysterious while (ii) seems to require assuming the sceptic is wrong.

Nonetheless contemporary epistemologists tend to favour the second approach. (Some claim that reflective equilibrium is ultimately

the right answers.)

3. The JTB account of knowledge

The JTB account is an account according to which knowledge is justified true belief.

According to the JTB account, justification, truth, and belief are necessary and jointly sufficient conditions for knowledge S knows that p if and only if S has a justified true

belief that p.

3. The JTB account of knowledge

The conditions: Belief

Entities lacking a mind can't have propositional knowledge.

An entity that doesn't have beliefs can't be said to know. And specifically, if one doesn't have a belief that something is the case then one isn't in a position to know that that is the case.

3. The JTB account of knowledge

The conditions: Belief

In the case of propositional knowledge: If Marina doesn't believe that it's raining outside, then how can she be said to know that it's raining outside?

(Beliefs may be occurrent (beliefs that we are actually entertaining), while most of our beliefs are non-occurrent.)

3. The JTB account of knowledge

The conditions: Belief

Case: Walter comes home and sees that his house has burnt down. He says “I don't believe it”, but he sees it so can't he be said to know it?

The orthodox view is that what Walter says is not strictly speaking true, rather what he says is best understood as conveying that he finds it hard to come to terms with what has happened. (Ichikawa and Steup, 2012).

3. The JTB account of knowledge

The conditions: Belief

Radford's (1966) case:

“Suppose Albert is quizzed on English history. One of the questions is: “When did Queen Elizabeth die?” Albert doesn't think he knows [the suggestion being that he doesn't believe], but answers the question correctly. Moreover, he gives correct answers to many other questions to which he didn't think he knew the answer”, so it's not a lucky guess. (Ichikawa and Steup, 2012).

3. The JTB account of knowledge

The conditions: Belief

One way of responding to Radford's case is to say that the suggestion is mistaken, and that Albert answering such questions correctly indicates that he has tacit or non-occurrent beliefs as to what the right answers are.

3. The JTB account of knowledge

The Conditions: Truth

So knowledge requires belief, but not all beliefs are knowledge.

Why think that truth is a necessary condition for knowledge?

We couldn't say that S knows that p if it's false that p.

3. The JTB account of knowledge

The Conditions: Truth

The conception of truth drawn on is one according to which there is a mind independent reality.

So generally my thinking or wanting p to be the case has no bearing on p being the case.

3. The JTB account of knowledge

The Conditions: Justification

As merely having a belief doesn't seem sufficient for knowledge, neither does merely have a true belief.

Sometimes someone gets something right, but just because they get something right, it needn't be that they know.

3. The JTB account of knowledge

The Conditions: Justification

Example:

Suppose S believes red will come up in the next roulette spin, but that S believes this because black has come up in the previous five consecutive spins. Given what we know about probabilities, and assuming there is no cheating, then what has come up in previous spins provides no basis for believing what will come up in a future spin.

S has a true belief but he doesn't know that red will come up in the next spin.

3. The JTB account of knowledge

The Conditions: Justification

The thought is that in such a case the agent just happens to get it right or is lucky to get it right, and that such cases aren't cases of knowledge.

By saying a belief needs to justified if it is to be a candidate for knowledge, we're saying that a belief must be formed in the right way. (Having a “justified” belief needn't imply that the belief is true).

4. Gettier cases

Suppose that John looks at a clock. The clock has correctly told the time over a long period. The clock indicates that it is 8 o'clock. It is in fact 8 o'clock. John forms the justified true belief that it's 8 o'clock. But now further suppose that the clock stopped exactly 12 hours previous to John looking at it.

Does John know that it's a 8 o'clock? Intuitively, no.

4. Gettier cases

Gettier cases are cases in which an agent has a justified true belief but not knowledge. Consider “The Sheep in a Field” case, another Gettier case:

Using his reliable perceptual faculties, Roddy non-inferentially forms a belief that there is a sheep in the field before him. His belief is also true. Unbeknownst to Roddy, however, the truth of his belief is completely unconnected to the manner in which he acquired this belief since the object he is looking at in the field is not a sheep at all, but rather a sheep-shaped object which is obscuring from view the real sheep hidden behind. (Chisholm, 1977: 105).

4. Gettier cases

A feature of the cases described is that though the agent's justified belief is off track, through epistemic luck (more specifically, doxastic luck), the agent's belief nevertheless turns out to be true.

Knowledge seems to have an internal and an external component that need to be linked in the right way in order for the there to be knowledge.

4. Gettier cases

We might think that the solution to the Gettier case is to require a causal connection between an agent's belief that p and her belief being true.

For example, that S's belief that p is causally connected to the truth of p.

4. Gettier cases

But now consider the “The Barn-Façade County case”, another Gettier case:

Using his reliable perceptual faculties, Barney non-inferentially forms a true belief that the object in front of him is a barn. Barney is indeed looking at a barn. Unbeknownst to Barney, however, he is in an epistemically unfriendly environment when it comes to making observations of this sort, since most objects that look like barns in these parts are in fact barn façades.

4. Gettier cases

There is the mentioned causal connection, Barney is looking at a real barn, he's not like Roddy who was only looking at a sheep shaped object.

Yet the standard intuition among epistemologists is this also is not a case of knowledge. The way Barney formed his belief is such that he could have easily been wrong.

5. Conclusion

The focus of epistemology is the study of knowledge.

The problem of the criterion is a challenge to providing an account of knowledge.

5. Conclusion

The JTB account of knowledge: Each of the conditions appear to be necessary and jointly sufficient.

The Gettier counterexamples show that this is not so.