Jonathan L. Kvanvig

Motivated by Plantinga's work, fourteen prominent philosophers have written new essays investigating Plantingian warrant and its contribution to contemporary epistemology. The resulting collection, representing a broad array of views, not only gives readers a critical perspective on Plantinga's landmark work, but also provides in one volume a clear statement of the variety of approaches to the nature of warrant within contemporary epistemology and to the connections between epistemology and metaphysics.

Alvin Plantinga thinks Leibniz made a mistake. Leibniz claimed that God could have created any possible world, but Plantinga thinks this view amounts to a lapse in judgment on Leibniz =s part. = Plantinga terms this mistake ALeibniz= Lapse,@ and his rejection of this Leibuizian claim plays an important role in Plantinga =s free wili defense against the problem of evil. I will argue that Plantinga fails to show that Leibniz lapsed in thinking about which worlds are actualizable by God; in particular, his argument for this claim is not sound. If I am right, the last lapse is on Plantinga

Alvin Plantinga and John Pollock both think that coherentism is a mistaken theory of justification, and they do so for different reasons. In spite of these differences, there are remarkable connections between their criticisms. Part of my goal here is to show what these connections are. I will show that Plantinga’s construal of coherentism presupposes Pollock’s arguments against that view, and I will argue that coherentists need not breathe their last in response to the contentions of either. Coherentism may be a mistaken theory of justification, but if it is, it is not shown to be so by either Plantinga or Pollock

The view I've been defending in the theory of justification I have termed ‘propositionalism’. It counsels beginning inquiry into the nature of justification by adopting a particular form of evidentialism, according to which the first task is to describe the abstract relation of evidencing that holds between propositional contents. Such an approach has a variety of implications for the theory of justification itself, and many of the motivations for the view are of a standard internalist variety. Some of these motivations will be described in due course, but there is also a further motivation to mention here as well. Such a theory, beyond enabling a theory to satisfy typical internalist strictures, also allows a strong relationship between the theory of justification and more standard confirmation theory where claims are confirmed and disconfirmed by information gleaned from experiments and other sources. It is a natural and pleasing result if confirmation theory can be embedded within the theory of justification developed in the context of more traditional epistemology.

There are two different kinds of theories of the concept of epistemic defeat. One theory begins with propositional relationships, only by implication describing what happens in the context of a noetic system. Such a theory places inforrmation about defeat up front, not informing us of how the defeat relationships play out in the context of actual belief, at least not initially. The other theory takes a back door to the concept of defeat, assuming a context of actual belief and an entire noetic system, and describing defeat in terms of what sort of doxastic and noetic responses would be appropriate to the addition of particular pieces of information. Where the house is the noetic structure itself, the front door approach characterizes the concept of defeat in terms of the propositional contents a belief might have, thus characterizing defeat at the front door. The backdoor approach characterizes defeat in terms of what leaves the house, in terms of beliefs that exit the noetic system in response to changes to it, in terms of what the staff of a well-run household kicks out the backdoor for making a mess of things. Alvin Plantinga’s theory of epistemic defeat is a back-door theory, and here I will argue that his theory and approaches like it will be unable to explicate accurately the concept of epistemic defeat. I will argue that a front door approach is needed rather than a back door approach

Suppose we want to know whether a person justifiably believes a certain claim. Further, suppose that our interest in this question is because we take such justification to be necessary for knowledge. To justifiably believe a claim requires more than there being a justification for that claim. Presumably, there is a justification for accepting all sorts of scientific theories of which I have no awareness; because of my lack of awareness, I do not justifiably believe those theories. Further, even if I, by chance, did believe one of those theories, I might not justifiably believe it; for I may be completely unaware of any justification for it. I then would not believe it..