RI Gettier Problem 2023

RI KI Y5 Knowledge & Justification: JTB 1 Reading: The Gettier Problem Before Gettier's essay below was published, most analytic philosophers took it for granted that something we might call the JTB account of knowledge was correct. The JTB account claims that knowledge can be conceptually analyzed as justified true belief. But Gettier came along and seriously called JTB into question. See if you agree with him. Edmund Gettier currently teaches at the University of Massachusetts. Gettier Is Justified True Belief Knowledge? Edmund L. Gettier From Analysis 23 ( 1963): 121-123. Transcribed into hypertext by Andrew Chrucky, Sept. 13, 1997. Various attempts have been made in recent years to state necessary and sufficient conditions for someone's knowing a given proposition. The attempts have often been such that they can be stated in a form similar to the following:1 a. S knows that P IFF i. P is true, ii. S believes that P, and iii. S is justified in believing that P. For example, Chisholm has held that the following gives the necessary and sufficient conditions for knowledge:2 b. S knows that P IFF i. S accepts P, ii. S has adequate evidence for P, and iii. P is true. Ayer has stated the necessary and sufficient conditions for knowledge as follows:3

RI KI Y5 Knowledge & Justification: JTB 2 c. S knows that P IFF i. P is true, ii. S is sure that P is true, and iii. S has the right to be sure that P is true. I shall argue that (a) is false in that the conditions stated therein do not constitute a sufficient condition for the truth of the proposition that S knows that P. The same argument will show that (b) and (c) fail if 'has adequate evidence for' or 'has the right to be sure that' is substituted for 'is justified in believing that' throughout. I shall begin by noting two points. First, in that sense of 'justified' in which S's being justified in believing P is a necessary condition of S's knowing that P, it is possible for a person to be justified in believing a proposition that is in fact false. Secondly, for any proposition P, if S is justified in believing P, and P entails Q, and S deduces Q from P and accepts Q as a result of this deduction, then S is justified in believing Q. Keeping these two points in mind, I shall now present two cases in which the conditions stated in (a) are true for some proposition, though it is at the same time false that the person in question knows that proposition. Case I Suppose that Smith and Jones have applied for a certain job. And suppose that Smith has strong evidence for the following conjunctive proposition: d. Jones is the man who will get the job, and Jones has ten coins in his pocket. Smith's evidence for (d) might be that the president of the company assured him that Jones would in the end be selected, and that he, Smith, had counted the coins in Jones's pocket ten minutes ago. Proposition (d) entails: e. The man who will get the job has ten coins in his pocket. Let us suppose that Smith sees the entailment from (d) to (e), and accepts (e) on the grounds of (d), for which he has strong evidence. In this case, Smith is clearly justified in believing that (e) is true. But imagine, further, that unknown to Smith, he himself, not Jones, will get the job. And, also, unknown to Smith, he himself has ten coins in his pocket. Proposition (e) is then true, though proposition (d), from which Smith inferred (e), is false. In our example, then, all of the following are true: (i) (e) is true, (ii) Smith believes that (e) is true, and (iii) Smith is justified in believing that (e) is true. But it is equally clear that Smith does not know that (e) is true; for (e) is true in virtue of the number of coins in Smith's pocket, while Smith does not know how many coins are in Smith's pocket, and bases his belief in (e) on a count of the coins in

RI KI Y5 Knowledge & Justification: JTB 3 Jones's pocket, whom he falsely believes to be the man who will get the job. Case II Let us suppose that Smith has strong evidence for the following proposition: f. Jones owns a Ford. Smith's evidence might be that Jones has at all times in the past within Smith's memory owned a car, and always a Ford, and that Jones has just offered Smith a ride while driving a Ford. Let us imagine, now, that Smith has another friend, Brown, of whose whereabouts he is totally ignorant. Smith selects three place names quite at random and constructs the following three propositions: g. Either Jones owns a Ford, or Brown is in Boston. h. Either Jones owns a Ford, or Brown is in Barcelona. i. Either Jones owns a Ford, or Brown is in Brest-Litovsk. Each of these propositions is entailed by (f). Imagine that Smith realizes the entailment of each of these propositions he has constructed by (f), and proceeds to accept (g), (h), and (i) on the basis of (f). Smith has correctly inferred (g), (h), and (i) from a proposition for which be has strong evidence. Smith is therefore completely justified in believing each of these three propositions, Smith, of course, has no idea where Brown is. But imagine now that two further conditions hold. First Jones does not own a Ford, but is at present driving a rented car. And secondly, by the sheerest coincidence, and entirely unknown to Smith, the place mentioned in proposition (h) happens really to be the place where Brown is. If these two conditions hold, then Smith does not know that (h) is true, even though (i) (h) is true, (ii) Smith does believe that (h) is true, and (iii) Smith is justified in believing that (h) is true. These two examples show that definition (a) does not state a sufficient condition for someone's knowing a given proposition. The same cases, with appropriate changes, will suffice to show that neither definition (b) nor definition (c) do so either. Notes 1. Plato seems to be considering some such definition at Theaetetus 201, and perhaps accepting one at Meno 98. 2. Roderick M. Chisholm, Perceiving: A Philosophical Study (Ithaca, New York: Cornell University Press, 1957), p. 16. 3. A. J. Ayer, The Problem of Knowledge (London: Macmillan, 1956), p. 34. [Source: http://www.ditext.com/gettier/gettier.html]

RI KI Y5 Term 1/Week 10 Knowledge & Justification: JTB 4 Discussion Questions 1) Consider this variation of the Gettier Problem: Farmer Field is concerned about his prize cow, Daisy. In fact, he is so concerned that when his dairyman tells him that Daisy is in the field happily grazing, he says he needs to know for certain. He doesn’t want just to have a 99 per cent idea that Daisy is safe, he wants to be able to say that he knows Daisy is okay. Farmer Field goes out to the field and standing by the gate sees in the distance, behind some trees, a white and black shape that he recognizes as his favourite cow. He goes back to the dairy and tells his friend that he knows Daisy is in the field. (At this point, does Farmer Field really know it?) The dairy man, Farmer Field’s assistant, says he will check too, and goes to the field. There he finds Daisy, having a nap in a hollow, behind a bush, well out of sight of the gate. He also spots a large piece of black and white paper that has got caught in a tree. Daisy is in the field, as Farmer Field thought. But was he right to say that he knew she was? (Discuss again if Farmer Field was right.) [Adapted from Cohen’s 101 Philosophy Problems] 2) To see if you have fully understood Gettier’s point, see if you can construct an example (like this Farmer Field one) where you illustrate the Gettier problem. 3) What are your reactions to the Gettier Problem? Do you accept Gettier’s argument? 4) One way to think of the Gettier Problem is as follows: x knows that p iff (i) x believes that p (ii) it is true that p epistemic glue (justification) Good reason: ¬ (justification ® truth) Certainty: (justification ® truth) Superglue Normal glue leads to Skepticism