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Epistemology Tihamér Margitay – Péter Hartl 6. Reliabilism.

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Presentation on theme: "Epistemology Tihamér Margitay – Péter Hartl 6. Reliabilism."— Presentation transcript:

1 Epistemology Tihamér Margitay – Péter Hartl 6. Reliabilism

2 Knowledge, truth, and belief What is knowledge? S knows that p (where p is a proposition), only if S believes that p and p is true. But having a true belief is not a sufficient condition of knowledge. S may believe p, and p happens to be true, but S doesn't have adequate (or any) reasons for believing p. Example: S is a pathological optimistic person. Every week he believes that he will win the lottery. And all of a sudden, on one of the weeks, his numbers win. He has a true belief, but S didn't know that his ticket will win.

3 Analysis of knowledge „What is justification?” is an important question. According to the traditional conception, knowledge requires justification. „What is knowledge?” Traditional analysis: Knowledge = justified true belief

4 S knows that p, if and only if... 1. Belief: S believes p. 2. True: p is true. If it is incorrect then - no matter what else is good or useful about it - it is not knowledge. It can feel to the believer as if it is true, but it doesn't matter. If the belief is mistaken, it would be knowledge, no matter how much it might feel to the believer like knowledge. 3. Justification: p is justified. p needs to be well supported, being based on evidence or some other kind of rational justification. The belief, even if it is true, may as well be a lucky guess.

5 Gettier-cases Edmund Gettier challenged this traditional account of knowledge. He used counterexamples. He described possible situations in which all of these conditions obtain, but we wouldn't count it as knowledge. Therefore, knowledge is not justified true belief.

6 Gettier's original example Smith and Jones have applied for the same job. Smith has been told by the company president that Jones will win the job. Smith has observed that Jones has 10 coins in his pocket. He infers that whoever will get the job has ten coins in their pocket. But Smith who will get the job, and Smith himself has ten coins in his pocket. Nevertheless, neither of those facts was known by Smith. Smith has a justified and true belief: „Who will get the job has ten coins in his pocket.” But Smith doesn't have knowledge.

7 Other examples Chisholm's example: The sheep in the field. You are standing outside a field. You see, within it, what looks exactly like a sheep. You believe that there is a sheep in the field. And in fact you are right, because there is a sheep behind the hill in the middle of the field. You cannot see that sheep, though, and you have no direct evidence of its existence. Moreover, what you are seeing is actually a dog, disguised as a sheep. Hence, you have a well justified and true belief that there is a sheep in the field. But is that belief knowledge?

8 Other examples A modified version of Gettier's second example Smith believes that one of his colleagues has a Ford. He has good reasons for believing this: Jones always had a Ford, and Smith has seen him recently in a Ford. But Jones's Ford was stolen yesterday, and he drives a rented car. Nonetheless, one of Smith's other colleagues, Brown has a Ford. But Smith doesn't know these facts. He has a justified and true belief („One of my collegues has a Ford”), but he doesn't have knowledge.

9 The structure of Gettier cases Each Gettier case contains a belief which is true and well justified without being knowledge. Two important features of Gettier cases: 1. Fallibility: The justification is fallible (there can be mistakes). It gives strong reasons to believe p, but leaves open the possibility of the belief’s being false. Justification indicates strongly that the belief is true, without proving conclusively that it is. 2. Luck: The well (but fallibly) justified belief is true by luck. There are odd circumstances in the case, which make the existence of that justified and true belief unexpected.

10 Possible solutions 1. Infallibility: There is no fallible justification. In Gettier cases the subject doesn't have a justified belief, because it is (and can be) mistaken. Justified belief = If p belief is justified, then it is not possible to be false. Contradiction: justification can lead to false beliefs We don't allow that one’s having fallible justification for a belief that p could ever adequately satisfy JTB’s justification condition. In Gettier cases the subjects don't have knowledge, since they don't have a real (infallible) justification.

11 Problem with infallibility It is a drastic and mistaken solution. In „ordinary” situations we think that we have knowledge, yet we rarely (if ever) possess infallible justification of a belief. If we accept that infallible condition, then we can have knowledge only if we cannot be mistaken. But there are very few things (if any), which are infallible. The infallibilist conception of justification leads to sceptical conclusions: we don't know anything at all.

12 Possible solutions 2. Eliminating false evidence The subject lacks knowledge, because he is relying upon false evidence. He has luckily derived a true belief, p from a false belief and this is because he doesn't have knowledge. Smith includes in his evidence ('the president told me that..') the false belief that Jones will get the job. If Smith had lacked that evidence, he would not have inferred belief p. If so, he wouldn't have had a justified and true belief, which failed to be knowledge. JTB must be modified: no belief is knowledge if the person’s justificatory support for it includes something false.

13 Problems with eliminating false evidence A Gettier case can be formulated, when there is no false belief at all. Suppose: Smith has a belief: „The president of the company told me that Jones would get the job.” Suppose: Smith doesn't infer to: „Jones will get the job.” His belief (together with „Jones has ten coins in his pocket”) also supports this true belief that: „whoever will get the job has ten coins in their pocket”. Therefore this solution is not useful.

14 Problems with eliminating false evidence Probably, there is always some false evidence being relied upon, at least implicitly. If there is some falsity among the beliefs you use, but if you do not wholly remove it or if you do not isolate it from the other beliefs you are using, then you don't have knowledge. Therefore, we have again the threat of scepticism.

15 Possible solutions G. examples demonstrated that, a subject can obtain true beliefs with very solid grounds and yet the agent could still easily have been wrong. It is only by luck or coincidence that the agent’s source of justification leads to true belief. Epistemic luck: The justification leads to true belief by coincidence. To have a proper theory about knowledge, we have to eliminate the epistemic luck.

16 Appropriate causality 3. Eliminating inappropriate causality What is the connection between the justification, believing in the proposition, the truth of proposition, and knowledge? Goldman's response: Knowledge = true belief which is caused in an appropriate way. In Gettier cases, S doesn't have knowledge, because his true belief is caused in an „abnormal way”. Knowledge is constituted by two factors. The true belief AND the way as it was formed by a causal process constitute knowledge.

17 Causal theory of knowledge Alvin Goldman's causal theory of knowledge: S knows p, if and only if: the same fact which makes p true causes S's belief p. The fact what makes p true must be included in the causal process which produces the belief p. There is an appropriate causal relation between the belief p and fact which makes p true.

18 Gettier examples and causal theory In Gettier cases, the subject doesn't have knowledge, because the causal connection between the facts which make the belief true, and his belief is missing. Gettier I.: Smith believes that „the person who will get the job has 10 coins in his pocket”, not because the facts which make his belief true: „Smith (will) get the job.” ; „Smith has 10 coins in his pocket.” Why Smith does believe this? Because he believes that Jones will get the job (because the president told that), and Jones has 10 coins in his pocket. He has evidences for these beliefs, but these facts are not relevant to the truth of the original belief (the person who will get the job, has 10 coins in his pocket.)‏

19 Gettier cases and the causal theory Modified version of Gettier's second case: „One of my collegues has a Ford.” This proposition is true, because Brown has a Ford (but Smith doesn't know this). But this fact plays no role in his belief forming process. Smith believes this, because he believes that Jones has Ford. There is no causal connection between the fact which makes his belief true, and his belief.

20 Perception By perception we can aquire knowledge by causal processes. If the perceived object (Stoczek building) causes my belief that „It is the Stoczek building in front of me.”, and my belief is true, then I know that it is the Stoczek building. In memory, there is a causal realition between my present mental state (I can remember that..) and a past experience. I belive that 'I have seen the Stoczek building this morning', beause I have actually seen the Stoczek building.

21 Appropriate causal connection? Problem: What is an appropriate causal connection? Suppose: Smith believes that one of his colleagues owns a Ford, because Mr. Black has told him that Jones has bought a new Ford. And Mr. Black usually doesn't lie. But in this case Mr. Black remembers wrong, he has seen Brown buying a new Ford. In this case: Smith's belief „One of my colleagues has a Ford” has a certain kind of causal relation with the fact which makes it true (Brown has Ford), but in this case Smith doesn't have knowledge.

22 Reliabilist theory Reliabilism: An improved version of causal theory. Appropriate causal connection - > reliable cognitive process Causal theory: local theory of knowledge. It gives an answer to the question: whether the specific cause of a true belief is sufficient for knowledge. Reliabilism: general theory of knowledge. Question: whether the general belief-forming process by which S formed the belief that p would produce a high ratio of true beliefs. Whether a process is reliable in general or not?

23 Reliabilist theory Justificational status of a belief must somehow depend on the way the belief is caused. Wishful thinking or guessing are not proper ways of justification. Suppose Smith justifiably believes p. And p logically entails q. Does it follow that, if Smith believes q, then he has a justified belief? Not necessarly. If Smith doesn't notice that p entails q and believes it only because he wishes it were true. Then her belief in q isn't justified.

24 Having good reasons vs. justification There is a significant difference between merely having good reasons for one’s belief that Brazil will win the Football World Cup in 2014 and basing one’s belief on those good reasons. S may have excellent reasons for believing Brazil will win: they have a fantastic forwards, they will play at home, etc. Nonetheless S may believe that Brazil will win based on wishful thinking. (She would like it very much if it would be so.) In this case her belief is not justified.

25 Reliable and unreliable processes Wishful thinking, confused reasoning, guessing and hasty generalisation. Their common feature is unreliability: they tend to produce false beliefs in a large proportion of the cases. Remembering, good inductive reasoning. What do these processes have in common? They all reliable: most of the beliefs that each process produces are true.

26 Definition of justification Goldman: the definition of an (ultimate) epistemic term should rely upon only non-epistemic terms, otherwise the definiton would be empty of circular. Epistemic terms: justified, knowledge, having good reasons, having evidences, demonstrated. Non-epistemic terms: belief, truth, cause...

27 Reliabilism A belief is justified if and only if it is produced by a reliable cognitive process. A cognitive process is reliable if and only if it causes true beliefs frequently. The degree of reliability consists in the proportion of beliefs produced by the process that are true. Cognitve process: there are input(s) and outputs. The inputs may be beliefs or perceptual states (experiences), or introspective states, etc. Outputs are beliefs. A reliable process makes (probably) true beliefs (as outputs) from justified beliefs as inputs.

28 „History” of justification A reliable inference process provides justification to an output belief, if its input beliefs were themselves justified. How could the justifiedness of the inputs have arisen? By having been caused by earlier reliable processes. This chain must end in reliable processes having only non-doxastic inputs, such as perceptual inputs. Thus, justifiedness is a matter of a history of personal cognitive processes. This historical nature of justifiedness implied by reliabilism, and contrasts sharply with (internalist) foundationalism and coherentism.

29 Relibilist theory of knowledge What is knowledge? - > What is justified belief? This theory in a sense requires 'justification', but this justification differs from the former theories (foundatonalism, and coherentism). (other versions deny that knowledge requires justification.)‏ At least since Desacrtes, philosophers have traditionally thought of justification internalistically, such that S’s belief is justified only if S is in a position to produce reasons or evidence to support her belief. Opposed to these theories Goldman has an externalist theory.

30 Internalist and externalist theories of justification The rise of internalist-externalist debate is due to Gettier's article. What are the relevant factors of justification? Internalism: (1) Knowledge requires justification and (2) the nature of this justification is completely determined by a subject’s internal states or reasons. Externalism: denies at least one of these commitments: (1) either knowledge does not require justification or (2) the nature of justification is not completely determined by internal factors alone.

31 Internalism Internalism: justification of a proposition is completely determined by one’s internal states. Internal states: one’s bodily states, one’s brain states, one’s mental states (if these are different than brain states), or one’s reflectively accessible states. Foundationalism and coherentism are internalist theories. The justification is in my „head”. The justifiability of p depends only on my internal states (my beliefs and non-propositional states, such as experiences). A p belief is justified, if the subject has good (sufficient) evidences of p.

32 Internalism Internal states as either reflectively accessible states or mental states. Therefore, according to internalism I need to have an access to the factors which make my belief justified. Crucial point: A person either does or can have a form of access to the basis for knowledge or justified belief. The subject is (is able to) aware of the ground, basis of her knowledge or justified belief. (And we can ask for justification: how do you know that... )‏

33 Externalism Externalism: Justification depends on additional factors that are external to a person. The facts that determine a belief’s justification include external facts such as whether the belief is caused by the state of affairs that makes the belief true, whether the belief is counterfactually dependent on the states of affairs that makes it true, whether the belief is produced by a reliable belief producing process. (There are various versions of externalism.)‏

34 Justification without awareness Causal origins of one’s beliefs are not, in general, reflectively accessible. (causal theory of justificaton)‏ Externalists deny that one always can have (reflective) access to the basis for one's knowledge and justified belief. I don't need to know the basis of my knowledge or justified belief. If my belief is produced by (for example) reliable process, then my belief is justified, even if I'm not aware the facts which make my belief justified. (Example: Testimonial knowledge. I can't remember the „evidences” on which my belief that 'Napoleon lost at Waterloo'. But I don't need to remember, if my belief was proced by reliable processes.)‏

35 Justifiably justified justified... Externalism implies that there is no guarantee that someone who justifiably believes P is also justified in believing that she justifiably believes P. We don't need a further (meta) justification of the justifiability of my belief (or the reliablity of a cognitive process.)‏ Therefore the problem of regress is not harmful for the externalist. Weaker condition: There must be no reliable process available to the subject that, were it used by the subject in addition to the process actually used, would result in her not believing P.

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