Foundationalism

Wilfrid Sellars and Laurence BonJour have argued against non-inferential justification, on the ground that one is justified in holding a belief only if one has good reason to think that the belief is true. This ground, they suggest, implies that the justification of an alleged foundational belief will depend on an argument of this type:

1. My foundational belief that P has feature F.
2. Beliefs having feature F are likely to be true.
3. Hence, my foundational belief that P is likely to be true.

If the justification of alleged foundational beliefs depends on such an argument, these beliefs will not actually be foundational. Their justification will depend on the justification of other beliefs, namely, the beliefs represented by premises (1) and (2).

The justification of one's belief that P, however, does not require justified belief that premises (1) and (2) are true. Given such a requirement, I will be justified in believing that P only if I am justified in believing that my belief that P has feature F. Given these requirements, I will be justified in believing that (1) my belief that P has F only if I am justified in believing an additional proposition: that (4) my belief that (1) has F. In that case, we have no plausible way to preclude that similar requirements apply to the latter proposition—namely, (4)—and to each of the ensuing infinity of required justified beliefs. We do not have, however, the required infinity of increasingly complex beliefs. The conclusion is that if the justification for a belief must be accessible to a person holding the belief, that accessibility should not itself be regarded as requiring further justified belief. Some critics of foundationalism have missed this conclusion.

Current debates over internalism and externalism regarding justification concern what sort of access, if any, one must have to the justification for one's justified beliefs. Internalism incorporates an accessibility requirement of some sort on what provides justification, whereas externalism does not. Debates about internalism and externalism are prominent in contemporary epistemology and show no sign of easy resolution.