Post-Gettier Accounts of Knowledge
Before leaving her office, Joan always places her laptop on the corner of her desk. Unbeknownst to her, the laptop has just been stolen and is now sitting on the corner of a desk in the thief’s apartment. Joan believes that her laptop is on the corner of a desk, and in fact it is, but she doesn’t know this.
On Tuesday evening Mary went to sleep at 11 p.m. as is her habit, unaware that she had been given a sleeping potion that would cause her to sleep thirty-two hours instead of her usual eight. When she awakes in her heavily curtained and clockless bedroom on Thursday morning, she believes it is about 7 a.m., because this is the hour at which she regularly wakes. It is 7 a.m., but she nonetheless doesn’t know this to be the case.
Jim has bought a ticket in a lottery of a million tickets. The winning ticket has been chosen but not yet announced. Jim believes that his ticket is not the winner and he is correct, but he lacks knowledge.
Examples such as these, which can be multiplied indefinitely, create an agenda for the theory of knowledge, that of identifying what has to be added to true belief in order to get knowledge. One tradition says that what is needed is something like an argument in defense of the belief, a justification to use the term of art. In an influential 1963 article, however, Edmund Gettier used a pair of examples to illustrate that justification on its own is not enough, and as a result the question became what has to be added to justified true belief in order to get knowledge?1
There has been no shortage of answers. Many have suggested that what is needed is a special kind of justification. The justification has to be nondefective in the sense that it must not justify any falsehoods,2 or it has to be indefeasible in that it cannot be defeated by the addition of any truth.3
A rival tradition maintains that justification-based approaches are misdirected. Since we often are not in a position to defend what we know, something less explicitly intellectual than justification traditionally understood is required to understand knowledge, in particular, something about the processes and faculties that produce or sustain the belief.
Again, there has been no shortage of proposals. One popular idea is that for a true belief to count as knowledge, it must be reliably generated.4 A second idea is that in close counterfactual situations, the subject’s beliefs about the matter in question would track the truth.5 A third is that the belief must be the product of properly functioning cognitive faculties.6 There are also important variants of each of these ideas.7
All these proposals assume that what needs to be added to true belief in order to get knowledge is something related to true belief but distinct from it—nondefective justification, indefeasible justification, reliability, truth tracking in close counterfactual situations, proper functioning, or whatever. My suggestion, by contrast, is that whenever an individual S has a true belief P but does not know P, there is important information she lacks.
What has to be added to S’s true belief P in order to get knowledge? More true beliefs. Especially more true beliefs in the neighborhood of P. In particular, there must not be important truths of which she is unaware, or worse, ones she positively disbelieves.
A merit of this view is that there is a straightforward way to test it. If S has a true belief P but does not know P, then according to the view it ought to be possible to identify a proposition Q such that (i) Q is an important truth and (ii) S does not believe Q.
Why does Joan not know that her laptop is on the corner of a desk, and Mary not know that it is 7 a.m., and Jim not know that his lottery ticket is not the winner, even though their beliefs are true? They lack key true beliefs about the situations in question. Joan isn’t aware that her laptop has been stolen and that the desk on which it now sits is that of the thief; Mary isn’t aware that she is just waking up from a drug-induced sleep; and Jim isn’t aware which ticket has won the lottery.
This in brief is the idea I will be developing, but I want first to take a step back to look at the role of examples such as these in the theory of knowledge.