Epistemic Coherentism and Foundationalism
Knowledge, as previously discussed, is analysed as justified true belief according to the classical definition. We established that truth is to be understood in an absolute – not relative – way and that belief is some form of intentional attitude of acceptance of some proposition. Justification, as noted, can be viewed in quite different ways. It can be said to be domain-specific and subject-relative. There are many other distinctions that can be made when it comes to epistemic justification. Some like to talk about the distinction between a priori justification and a posteriori justification, whereas some like to go on about internalism and externalism. The first distinction deals with justification prior to, and after, experience. The second one has to do with whether justification requires that we grasp claims that support some belief, or whether it suffices that the justification is e.g. truth-conducive. These are all very interesting topics, but for now I suggest that we look to another very basic distinction, namely the one between coherentism and foundationalism.
Where do we start? Why not from the bottom and reach our way to the top – at least theoretically speaking. Foundationalism is a view about the structure of epistemic justification. On this view some “basic” beliefs are, in themselves, credible and can lend their support to other “non-basic” claims which aren’t credible or self-evident in the same way. Say that you have the law of identity, namely the claim that “x = x”; i.e. the claim that a thing is identical to itself. This law may then support claims about particular entities, say that “the writer of this text is the writer of this text” or “Dumbo is Dumbo”. Assuming we accept the law of identity as credible, we can use it to support the latter claims as well. Foundationalism about epistemic justification therefore takes certain things from granted, and from these construct (abstractly speaking) a foundation on which other layers of justified beliefs can stand. Once a non-basic belief is justified, it can then justify yet other layers of non-basic beliefs. The ultimate justification for these non-basic beliefs lies, however, in the basic beliefs.
Coherentism, in turn, shifts from a bottom-up structure of justification into something more akin to a network. On this view, beliefs are not justified by other already credible beliefs. Instead we have systems or “networks” (if you will) of beliefs that are justified (or not). Whereas in foundationalism basic beliefs justify other non-basic beliefs, coherentism does not view the connections between beliefs as justifying relations as such. Instead it is the coherence of the web of beliefs – how well they hang together as a whole – that captures the idea of justification. Say that someone, Smith, has the belief that the sun is a large object, and the belief that objects take up space, and the belief that on a scale from smallest to largest of everyday objects we have the sun somewhere around the top, …, and so on. How well these beliefs Smith has “fit” with each other, and how many the connections between the nodes in the network are, is what ultimately what justifies them as a whole. Of course, one can speak of how well justified singular beliefs are insofar as one bears in mind that it is the coherence of this belief with some assumed set (or “web”) of beliefs that is ultimately justified. The justification of a singular belief is therefore, in a sense, derivative from the justification of what we might call a person’s web of beliefs.
Foundationalism and coherentism are two radically different theories of epistemic justification. Foundationalism seeks to build our knowledge from credible or indubitable beliefs at the bottom, to other beliefs that may not be so indubitable. Coherentism turns this picture on its side and views justification as a feature of a system of beliefs. On the coherentist view, it is not the relations between particular nodes (beliefs) in the network of beliefs that serve the justifying role. Rather, it is the system of relations as a whole that makes up the person’s epistemic justification for her beliefs.
 The term ‘epistemic’ is used here because it has to do with ‘epistemology’ or “the study and theory of knowledge”.