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The Gettier Problem No Longer a Problem

Lukasz Lozanski claims to know why Edmund Gettier was unjustified.

In 1963, Edmund Gettier challenged the whole notion of what constitutes knowledge. Until he published a short paper that year called ‘Is Justified True Belief Knowledge?’, it was widely accepted that knowledge was justified true belief. In other words, it was thought that if you believe something, and you have justification for believing it, and your belief is in fact true, then we can say that you know that thing. Using two examples, Gettier tried to show that it isn’t enough for these three conditions to be met. This problem has baffled philosophers ever since. However I don’t believe we should so hastily abandon the idea that knowledge is justified true belief, for as I will now show, Gettier’s examples were flawed in the first place.

Gettier’s Examples

The first example Gettier comes up with has to do with Jones and Smith applying for a job. If Smith had strong evidence that Jones will get the job (for example if the boss said Jones will get the job) and also that Jones has ten coins in his pocket (for example, Smith counted the coins in Jones’s pocket), then he might assert the following proposition:

A) Jones is the man who will get the job, and Jones has ten coins in his pocket.

This proposition entails that:

B) The man who will get the job has ten coins in his pocket.

If Smith sees this entailment and accepts proposition B on the grounds of proposition A, then with the given evidence, Smith is justified in believing proposition B. It turns out that Smith himself will unexpectedly be offered the job, and by random chance Smith also has ten coins in his pocket. Now B is true even though A is false. Thus, proposition B is true, Smith believes that B is true, and Smith is justified in believing B is true. However, Smith does not know that proposition B is true. He doesn’t even know how many coins he has in his own pocket. He bases his belief on the number of coins in Jones’ pocket. So, says Gettier, Smith has a justified true belief in proposition B, but he doesn’t know proposition B.

Even if we allow Gettier to make proposition B (a very broad statement) on the grounds of proposition A(a very specific statement); and even if we allow Smith’s evidence to be sufficient for true knowledge (basing his beliefs on what someone says without any further proof or evidence for that claim), other problems arise which cannot be overlooked.

Gettier makes a very specific statement (Jones is the man who will get the job, and Jones has ten coins in his pocket), and from that he deduces a very generalized statement, (The man who will get the job has ten coins in his pocket.) However, it is not clear who ‘the man’ refers to here. If ‘the man’ refers to Jones then the statement is false, because Jones is not the man who gets the job. If ‘the man’ refers to Smith, then Smith would be making a statement without any justification, since he believes that Jones will get the job. The first possibility violates the truth requirement for justified true belief, while the second case violates the justification requirement. Gettier has tried to use semantic obscurity to trick the reader into believing that justified true belief is not enough for knowledge. However, it can be seen that in this case the ‘knowledge’ was either not justified or false, and thus never constituted knowledge in the first place.

Gettier’s second example starts with Smith having strong evidence for the following proposition:

C) Jones owns a Ford.

Then we are told that Smith has a friend, Brown, whose whereabouts he does not know. Smith then selects three locations at random to construct the following propositions:

D) Either Jones owns a Ford, or Brown is in Boston;

E) Either Jones owns a Ford, or Brown is in Barcelona;

F) Either Jones owns a Ford, or Brown is in Brest-Litovsk

Propositions D, E and F are all entailed by C. Smith realizes this entailment and accepts D, E and F on the basis of C. Smith is justified in believing all of these propositions because he’s justified in thinking that Jones owns a Ford, even though he has no ideawhere Brown is located.

It turns out that Jones no longer drives a Ford, and by coincidence Brown is in Barcelona. In this case Smith does not know that proposition E is true, even though proposition E is true, Smith believes E is true and Smith is justified in believing E is true by having strong evidence for Jones owning a Ford.

Again, ignoring the fact that we cannot be sure Smith has adequate evidence for Jones owning a Ford (in the original paper Gettier says Jones has owned a Ford his whole life – in my opinion not much evidence at all), a serious problem arises.

This second example cannot be accepted because it contains an inherent logical flaw. Gettier uses an example in the form of ‘either a or b, not a, therefore b’. However, this form of logic can ‘prove’ an infinite number of impossibilities. For example, I have reason to believe that Brown is in Barcelona, so I say “Either cows fly or Brown is in Barcelona.” It turns out Brown is now in Amsterdam, therefore, cows fly. This is obviously impossible, thus showing that the formula can’t be used to prove anything ­– or else it could be used to prove everything! You cannot claim here to know a proposition which randomly happened to be true just because its complementary proposition which you thought was true wasn’t. This is the wrong ‘justification’. Conclusions derived using this logical sleight-of-hand cannot be considered knowledge.

One problem that it isn’t necessary to look at in order to undermine Gettier’s paper still deserves to be considered; this problem being what constitutes adequate justification. In both cases, justification for Smith comes from empirical evidence. Now, if someone has 100% (irrefutable) evidence for X and believes X is true, then that person is justified in believing X and is considered to have knowledge of X. On the other hand, if the person has 25% evidence for X and the person believes that X is true, then the person is not (adequately) justified in believing X and does not have knowledge of X. Justification depends upon evidence, and where we draw the line of when something is adequately justified based upon sufficient evidence is unclear (would 51% evidence for X be sufficient justification?). Gettier makes the assumption that the evidence presented justified Smith’s beliefs. However, Gettier makes no attempt at saying how strong the evidence is, and if we can infer anything it is that the evidence is quite weak, and it could be argued that in both cases Smith was not justified in making the statements of knowledge he made.

The problem of reference-muddling in example one and the inherent logical flaw in example two show that Gettier problems are no threat to ‘knowledge as justified true belief’. The classical definition of knowledge as justified true belief doesn’t have to be changed, and no extra premises have to be added.

© Lukasz Lozanski 2007

Lukasz Lozanski was born in Poznan, Poland and is currently a student of medicine at the Ohio State University. His favourite philosophers are Friedrich Nietzsche and the Japanese poet Ryokan. Questions or comments email:


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