The Gettier Cases and the Revision of Knowledge
To many philosophers, it has been the long-standing view that knowledge is defined as a justified, true belief. But does this definition accurately account for knowledge? Edmund Gettier proposes two cases in which this definition of knowledge proves insufficient. Some have criticized Gettier’s examples as invalid because they are based on false propositions. Still other philosophers agree with Gettier, and attempt to revise the definition to fix the “Gettier Problem.” Alvin Goldman proposes a 4th condition, known as “No False Lemmas,” that requires a causal connection between the belief of a given statement and the fact that makes the statement true, while Keith Lehrer and Thomas Paxson add a 4th condition that requires the evidence for a given belief to have no defeaters. Though Goldman, Lehrer, and Paxson give strong arguments for their respective revisions to the definition of knowledge, their alterations do not solve the Edmund Gettier Problem with absolute certainty.
What are the Gettier Cases?
The Gettier Cases seek to prove that the prevailing definition of knowledge is insufficient. Gettier argues that a Subject (S) can believe in a given Proposition (P), P can be true, and S can be justified in believing that P, but still not have knowledge of it. He illustrates this argument through two cases. In Case 1, Smith and Jones are applying for the same job. The president of the company tells Smith that Jones will definitely get the job. Smith asks to count the coins in Jones’ pocket and there are 10 coins. So (S) Smith comes to believe that (P) the man who will get the job has 10 coins in his pocket, and he is justified in believing this based on the evidence (E) that Jones will get the job and Jones has 10 coins in his pocket. However, unbeknownst to Smith, the president was mistaken and Smith will actually get the job instead of Jones and Smith also happens to have 10 coins in his pocket. So S believes that P, P is true, and S is justified in believing that P, but he does not have knowledge of P because his belief is based on Jones getting the job, which is false.
In Case 2, Smith believes that (P) Jones owns a Ford. Smith is justified in believing that P because he has seen Jones driving a Ford before and Jones recently offered to give Smith a ride in a Ford. In this case, a different friend of Smith’s named Brown is in a location that is unknown to Smith. Smith chooses three places at random to create 3 new propositions: (P1) either Jones owns a Ford, or Brown is in Boston, (P2) either Jones owns a Ford, or Brown is in Barcelona, and (P3) either Jones owns a Ford, or Brown is in Brest-Litovsk. Smith accepts all of these propositions because they all include P, and each proposition only requires that one half of the statement be true in order for the entire proposition to be true. But as it turns out, Jones does not actually own a Ford because it is rented, and Brown just happens to be in Barcelona. So S believes that P2, P2 is true, and he is justified in his belief that P2, but he does not have knowledge of P2 because his belief is based on P, which is false.
Though I will not expound on cinematic examples of the Gettier Problem in this essay, it is important to note that many films rely on the questionable acquisition of “knowledge.” One oft-overlooked film is John Candy’s Who’s Harry Crumb? about a bumbling detective who continuously stumbles upon the truth, despite doing everything in his power to miss it. For a more in-depth analysis of the film and its connection to the Gettier Cases, be sure to check out this essay.
Richard Feldman’s Revisions
Some critics argue that the Gettier Cases are invalid because they are based on false propositions. Richard Feldman defends the Gettier Cases against this criticism by adjusting the evidence used to justify S’s belief that P to make the original propositions true. For Case 1, Feldman simply takes the original evidence that “Jones will get the job and Jones has 10 coins in his pocket,” and adjusts it to make it true. The new proposition is: the president said that Jones will get the job and Jones has 10 coins in his pocket. Now the original proposition that justified Smith’s belief is true. For Case 2, Feldman makes the exact same change to the supporting evidence. The original proposition is that “Jones owns a Ford.” The revised proposition is “Jones said that he owns a Ford.” By re-wording the evidence, Feldman makes the propositions true and refutes the claims that the Gettier Cases are unfounded due to false propositions.
Alvin Goldman’s Revisions
Goldman agrees with Gettier that the definition of knowledge is insufficient, but Goldman proposes that it be amended with a 4th condition. This 4th condition adds the requirement of causal connection between S’s belief that P, and the fact that makes P true. Goldman argues for the necessity of this 4th condition through four distinct categories of “knowing” P: perception, memory, inference, and testimony. Concerning perception, Goldman uses the example: S sees a vase on the table. In the given scenario, there is a vase on the table, however there is also a hologram of a different vase being projected directly in front of the actual vase, obstructing S’s view of the real vase. Since S believes that he sees a vase, and this belief is based on his perception of the hologram, S does not have knowledge that the vase is on the table because S does not actually perceive it. There is no causal connection between S’s belief that P, and the fact that makes P true.
In the second category, memory, Goldman asserts that a person only has knowledge of an event if the event itself causes the memory of it. For example, if S remembers going to the zoo when he was young, and going to the zoo is the direct cause of the memory of the event, then S has knowledge of it. However, if another person tells S that he went to the zoo when he was younger, and S forms the belief that he went to the zoo based on this information, then S does not have knowledge because there was no causal connection between the event and S’s memory of the event.
In the third category, inference, Goldman argues that S can have knowledge of P by inferring that P, but only if the evidence for believing P has a direct causal connection with P. For example, if S walks outside and sees that the ground all around him is wet, he infers that it was raining before he walked outside. If the water was left over from rain, then S does have knowledge based on his inference. However, let’s say that it was raining the night before, but all the water dried up before S went outside, and a person dumped new water all over the ground. S would infer that it had rained, but since there is no causal connection between it raining and the water that is now on the ground, S would not have knowledge of it.
For the last category, testimony, person T comes to believe that P through their perception of P. T relates his belief that P to S, who infers that P is true based on T’s testimony. Goldman uses the example of a newspaper typo to stress the necessity of a causal connection for knowledge. A newspaper columnist (T) reports a given event, P, but the article has a typo that states “not P.” S reads the article, but misreads “not P” and infers that P is true. Since there was a break in the causal chain between the columnist’s testimony that P and S’s inference that P, S does not have knowledge of P.
Goldman provides a strong argument for adding a 4th condition to the definition of knowledge, but his argument does not solve the Gettier Problem with absolute certainty. Based on the Gettier Cases, Goldman is correct in assuming that the definition of knowledge should be amended, and the addition of causal connection does help explain both Gettier cases. Specifically, the 4th condition shows that in Case 1, there is no connection between Smith believing that Jones will get the job and the fact that someone with 10 coins in his pocket will get the job. The same goes for Case 2, because there is no causal connection between Smith believing that Jones owns a Ford and the fact that Brown is in Barcelona. Rather than solving the Gettier Problem though, it seems more accurate to say that Goldman merely explains why the Gettier Cases are valid. Goldman provides concrete reasoning that Smith definitely does not have knowledge of P, because the causal chain between Smith’s belief of P and the fact that makes P true was broken. However, the issue of what actually constitutes causal connectivity itself is what prevents Goldman’s theory from completely solving the Gettier Problem. Goldman avoids defining what the “causal connection” actually entails, and only states that if the “relevant causal process is absent,” we cannot say that S has knowledge of P (Pojman 130).
The Failings of Goldman’s 4th Condition
Goldman gives four different examples for the absence of causal connection, but never clearly states to what extent a causal chain must be present to render knowledge of P. Nor does he differentiate between a weak and strong causal chain. Assuming that, as it seems Goldman does, the “causal connection” refers to a direct line of reasonable causality between the fact that makes P true and the subject’s knowledge that P, I will construct a scenario where the subject believes P, P is true, the subject is justified in believing P, there is a causal chain between the belief that P and the fact that makes P true, but the subject does not necessarily have knowledge.
Let us assume that person A works at an office with persons B and D, and person D owns a Ford. A has perceived D driving a Ford down the road in front of the office every day for the last week. From this perception, A infers that (P) D owns a Ford. A then tells person B that P, and from this B infers that P is true, even though B has never actually perceived D driving in front of the office in a Ford. B then tells person C (who does not work at the same office as A, B, and D) that P. Specifically, B tells C that: “D owns a Ford. He was driving a Ford on the road in front of my office,” without explicitly stating who perceived it. C has no knowledge of A telling B that P, but C knows that B works at the same office as D. From this, C concludes that B could easily know that P through perception and infers that P must be true. So, C believes that P, P is true, C is justified in believing that P, and there is a causal connection between C’s belief that P (D owns a Ford) and the fact that makes P true (D was driving a Ford in front of the office). The causal chain is that P caused the belief of P in A through perception, A relayed P to B, B relayed P to C, and C made a justified inference based on B’s testimony that P is true. However, C’s belief that P is true is actually based on the assumption that B originally perceived P, because C has no knowledge of A or A’s perception of P. Therefore, C does not have knowledge of P because C’s belief that P is based on a faulty inference, even though there is causal connectivity between C’s belief that P and the fact that makes P true. This example shows that Goldman’s “causal connectivity” is too vague to completely resolve the Gettier Problem.
Keith Lehrer and Thomas Paxson’s Revisions
Much like Goldman, Keith Lehrer and Thomas Paxson seek to revise the definition of knowledge with their own 4th condition. Their 4th condition proposes that S only has knowledge of P if there is not a statement that can defeat S’s belief that P. More specifically, when evidence (E) completely justifies S in believing that P, statement Q defeats this justification if and only if (i) Q is true, and (ii) the conjunction of E and Q does not completely justify S in believing that P. Lehrer and Paxson also include another requirement under the 4th condition to eliminate poorly formed defeaters, that (iii) S is completely justified in believing that Q is false. Looking back at the first Gettier Case, the evidence is E: Jones will get the job. The defeater of this evidence is statement Q: Jones will not get the job. Q is true, and the conjunction of E and Q (Jones will get the job and Jones will not get the job) is contradictory. Therefore, S is not justified in believing that P, and as a result, S does not have knowledge of P.
Case 2 follows the same formula. The evidence is E: Jones owns a Ford. The defeater statement is Q: Jones does not own a Ford. Q is true, and the conjunction of E and Q (Jones owns a Ford and Jones does not own a Ford) is contradictory. Therefore, S is not justified in believing that P and S does not have knowledge of P.
The Failings of Lehrer and Paxton’s 4th Condition
Though this 4th condition does work for the Gettier Cases, it does not necessarily work when applied to Goldman’s examples of perception and testimony. In the case of perception, the evidence is E: there is a vase on the table. The defeater statement is Q: there is a hologram of a vase on the table. Q is true, and the conjunction of E and Q (there is a vase on the table and there is a hologram of a vase on the table) do not give sufficient justification for S to believe that P. However, it is the final requirement that makes Lehrer and Paxson’s revision problematic. S must be completely justified in believing that Q is false, but in this case, S is not completely justified in believing that there is not a hologram of a vase on the table. Therefore, Q does not completely defeat S’s belief that P.
The example of testimony yields the same results. The hypothesis is the generic statement (P) that was being reported on in the newspaper. Let us say that P is the statement: “the murderer got away.” The defeater statement is Q: There is a misprint. Q is true, and the conjunction of P and Q (the murderer got away and there is a misprint) does not give sufficient justification for S to believe that P. However, S is not completely justified in believing that there is a misprint. Therefore, Q does not completely defeat the S’s belief that P. Both examples show that Lehrer and Paxson’s adjustment to the definition of knowledge, while applicable to the original Gettier Cases, does not provide concrete justification for knowledge in every situation.
Conclusion
The Gettier Cases prove that the definition of knowledge as a “justified, true belief” is inadequate, but neither of the proposed revisions solve the issue of knowledge definitively. Goldman’s “causal connection” is too broad and vague to provide a definitive account for knowledge, while Lehrer and Paxson’s defeater condition simply does not make sense in conjunction with certain propositions. In conclusion, the arguments given by Goldman, Lehrer, and Paxson do not completely “fix” the Gettier Problem, leaving us with an account of knowledge that remains insufficient.
Louis P. Pojman, Theory of Knowledge: Classical and Contemporary Readings, third edition, Wadsworth, Inc., 2003, paperback.
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