Arrested Development and Philosophy_ They've Made a Huge Mistake - Kristopher G. Phillips [71]
Clearly then, not only must one have a belief and have justification for that belief, but the belief must also be true. And with this we’ve finally arrived at the traditional account of knowledge where knowledge is defined in terms of justified-true-belief (we’ll call it JTB). On this account, JTB is necessary and sufficient for knowledge; if someone knows something, it follows that her belief is justified and true. If someone has a belief that is justified and true, then she has knowledge.
With the traditional account in mind, let’s return to our original examples. If George Michael knows that he loves his cousin Maeby, then he must not only believe it, but also have justification for believing it (in this case all he needs is awareness of his own emotions). And, of course, his belief must also be true. Similarly, to say that Buster knows a great deal about agrarian business in the eighteenth century is to say that Buster has beliefs about eighteenth-century agrarian business (something having to do with how best to avoid an uprising perhaps?), that those beliefs are justified (Buster’s extensive academic background would likely provide him with the relevant sort of justification), and that his beliefs were true.
The traditional account seems to achieve our goal, but in recent decades it has met with serious scrutiny and almost universal rejection.
As You May or May Not Know [JTB] and I Have Hit a Bit of a Rough Patch . . .
Just as we used examples to show that mere belief (Tobias’s acting) or justified belief (Michael’s accident) are not sufficient for knowledge, the philosopher Edmund Gettier developed famous examples that are intended to show that JTB is itself not sufficient for knowledge. If Gettier is right, then the traditional account of knowledge would fail to provide necessary and jointly sufficient conditions for knowledge. The following two cases come from Gettier himself:2
Case 1: Best Man for the Gob . . . I mean, Job!
(1) I am justified in believing that Jones will get the job, and I am justified in believing that Jones has ten coins in his pocket.
(2) On the basis of (1) I deduce that the man with ten coins in his pocket will get the job.
(3) It turns out, unbeknownst to me, that I have ten coins in my pocket and I will get the job.
Case 2: Headed down old South-America Way, eh Brown?
(4) I am justified in believing that Jones owns a Ford.
(5) On the basis of (4) I deduce that either Jones owns a Ford, or Brown is in Barcelona.
(6) It turns out, unbeknownst to me, that Brown is in Barcelona.
In each of these Gettier cases it is granted that there is a justified belief, (1) and (4), respectively. It is then shown that the justified-belief can be used to entail (have as a required consequence) another claim, (2) and (5), respectively. The difficulty comes when we realize that we can have a justified-false-belief, which entails some other belief, and by sheer chance, the other belief turns out to be true; as with (3) and (6). Gettier concludes that, in both Case 1 and Case 2, we would have JTB but not knowledge.
While both of these Gettier cases rely on an explicit inference from one premise to another, philosophers have created Gettier-style cases so that there seems to be no inferential step at all.3 Consider another famous Gettier style case from Alvin Goldman:4
Case 3: It’s not a Real House, Mom . . . That’s All right, He’s not a Real Man.
(7) I am justified in my belief that the thing I am pointing at is a very nice barn.
(8) Unbeknownst to me, I am driving in Fake-Barn-County, where one in every four barns is real and the rest are barn-façades.
(9) As it turns out, the thing