Few philosophical articles have generated as much scholarship as Edmund Gettier’s 1963 piece in Analysis “Is Justified True Belief Knowledge.” In the article, Gettier provides two examples of beliefs that are both justified and true, but which he correctly assumes most philosophers would not accept as knowledge. What appears to have been overlooked in the flurry of responses to Gettier is the fact that the insight he presents into our understanding of what it means to know something was not new. Bertrand Russell had articulated the very same insight fifty years earlier in his The Problems of Philosophy.
Gettier’s article includes two counterexamples to the definition of knowledge as justified true belief. Both counterexamples work in the same way. That is, both involve an individual’s holding a belief the truth of which is logically entailed by another belief they hold which is both justified and assumed, wrongly as it turns out, to be true, and both count on justification being conferred via the relation of entailment. Since both examples work in the same way, for the sake of brevity I’ll consider only the first.
In this example, two men, Smith and Jones, have applied for the same job. Smith is described as having “strong evidence” that Jones will get the job, and that Jones has ten coins in his pocket. Smith’s evidence is described by Gettier as being sufficiently strong to justify his beliefs that Jones will get the job and that Jones has ten coins in his pocket. The conjunctive proposition “Jones is the man who will get the job, and Jones has ten coins in his pocket,” Gettier explains, entails a third proposition that “The man who will get the job has ten coins in his pocket.” Since Smith can see that belief in the truth of this proposition is entailed from the proposition whose truth he is justified in believing, he believes this proposition as well.
Included in the justification of Smith’s belief that Jones would get the job was that “the president of the company assured him that Jones would in the end be selected.” But, of course, the president could change his mind. And that is precisely what happens in Gettier’s example. Smith, not Jones, gets the job. It doesn’t take a great deal of imagination to envision this scenario. No amount of justification for beliefs relating to matters of empirical fact, at least no amount of the sort of justification Gettier presents (i.e., the kind available to introspection) can guarantee the truth of such beliefs.
What is more surprising, but certainly not implausible, is that Smith just happens to have ten coins in his pocket. So Smith’s belief that “The man who will get the job has ten coins in his pocket” is, as it turns out, both justified and true. That is, the belief is justified because is was entailed by Smith’s belief that Jones would get the job and that Jones had ten coins in his pocket. And it is true, because he, Smith, happens to have ten coins in his pocket as well.
Gettier correctly assumed, however, that despite the fact that Smith’s belief that “The man who will get the job has ten coins in his pocket” turned out to be both justified and true, that virtually no one would be willing to say that it constituted knowledge.
Gettier’s point wasn’t really all that original though. The problem is that Smith inferred a true belief from a false one. That is, he inferred the truth of the proposition “The man who will get the job has ten coins in his pocket,” from his belief in the truth of the proposition that “Jones is the man who will get the job, and Jones has ten coins in his pocket.” Jones didn’t get the job, however, he did, and “a true belief,” Russell explained back in 1912, “is not knowledge when it is deduced from a false belief.”
Russell’s example of a true belief that is inferred from a false belief is much simpler than Gettier’s in that it makes no reference to justification. His example involves someone believing truly that “the late Prime Minister’s last name began with a B” based on his false belief Balfour was the late prime minister. In fact, the belief that the late Prime Minister’s last name began with a B was true at the time Russell wrote The Problems of Philosophy because the late Prime Minister, at that time, was Henry Campbell Bannerman.
The entailment condition is implicit in Russell’s example because the proposition that “Balfour was the late Prime Minister” entails the proposition “The late Prime Minister’s last name began with a B.” Again, Russell’s example makes no reference to justification, but this omission in no way weakens the strength of his insight that true beliefs inferred from false ones can’t constitute knowledge. This is precisely the insight put forward by Gettier, though it’s dressed up in his paper with the trappings of justification and even more baroquely with the contrivance of conveying justification via the relation of entailment.
So Gettier’s paper, despite the splash it made, and indeed, to some extent continues to make, conveyed no philosophical insight into our intuitions about what it means to know something that had not already be conveyed by Russell fifty years earlier.