What is at Issue between Internalists and Externalists about Knowledge and Justification? Which Side is Right? There are a number of different ways that one may be said to have knowledge. It is possible to have knowledge of people, in the sense of being acquainted with them; or one can have the knowledge of how to do a task, as in cooking food; or one can know that something is the case such as ‘the sky is blue’. The latter of these is known as propositional knowledge and is what epistemology is most interested in. This is why knowledge is often philosophically defined as ‘justified true belief’.
For one to have knowledge, we think that they must fulfil these three conditions: it must be justified, be true, and be a belief held by someone. However there are counterexamples to this definition, with respect to the third criterion, known as Gettier-style problems. Assume John has two brothers, Paul and Edward. John has no idea where Edward is because he is travelling abroad, but he saw Paul buying and walking a dog and consequently believes that Paul owns a dog. Logically, we can validly say that John knows that ‘either Paul owns a dog or Edward is in New York’ even though he has no idea where Edward is.
Suppose however that the dog is not his, but a present for a friend, and also suppose that by luck Edward is in fact in New York. Therefore, in this scenario, John believes, with justification, a true proposition, but we would not want to say that he has knowledge. However, to try to circumvent this sort of counter example one could draw on a theory known as infallibilism. This states that ‘if it is true that S knows p, then S cannot be mistaken in believing p’, and therefore the justification for believing p guarantees its truth. In other words, one cannot be justified in believing a false proposition.
This view is rejected by fallibilists who argue that it is indeed possible for one to have justification for believing p although it is false. They purport to single out an error in its supporting argument. The truth of ‘S knows that p’ rules out the situation of it ‘being possible to be wrong about p if S knows p’ (Grayling). But this is different from saying that S is so placed that he cannot possibly be wrong about p. This although leaves a too narrow definition for knowledge because it says that S can justifiably believe p only when the possibility of p’s falsity is excluded. Rather, it appears that one can have the very best evidence for believing something, and yet be wrong, with epistemic experience.
The problem for fallibilists however is that one’s justification for believing p does not connect with the truth of p in the right way, as demonstrated by the Gettier-style problems. There are two approaches which attempt to do this: foundationalism and coherence theory. The majority of our normal beliefs need the support of others for their justification and this leads to a chain of justification. If this is not to be an infinite regress, then we need beliefs that were independently secure and the foundations for the rest.
On this view a justified belief can either be a foundational belief or one supported by it, and so we need to provide evidence as to how a foundational belief can be so. They must be either self-evident, indefeasible, incorrigible or justify themselves. Some have attempted to argue that instead of foundational beliefs we could use perceptual states because they are incorrigible. This is not a good solution though as perceptions require the application of prior beliefs, which again need justification. Likewise self-evident examples like logic appear to be of no help. They do not seem able to help in grounding contingent beliefs.
Critics of foundationalism can also argue that it is far from obvious how justification is transmitted from foundational beliefs to dependent beliefs: it is certainly too strong a claim to say that the dependent beliefs are deducible, and induction would require further supplementation. These sorts of criticisms have led some to instead defend coherence. They will argue that a belief is justified if it coheres with those in an already accepted set. The theory has its basis ‘in the notion of a system, understood as a set whose elements stand in mutual relations of both consistency and (some kind of) interdependence’ [Grayling].