With respect to holding certain beliefs about things (e.g., the existence of God, the existence of minds other than your own, etc.) we often hold to a criterion of knowledge regarding the grounds for the truth of the belief. Hence, let us ask for example, what might be the justifying grounds for say, believing that God exists? Is there evidence that supports the existence of God? Is there any counter-evidence? If there are equally as many supporting evidences and counter-evidences for belief in God, how do we decide from there? What if there is no evidence at all, for or against?
Philosophers – both theists and atheists – have for quite some time been divided on how to approach this issue. Although I don’t wish to exhaust those views here, I want to pay special attention to a given theory of knowledge fresh within circles found in the philosophy of religion known as Reformed Epistemology. This view (to offer a brief definition), simply says “that belief in God. . . does not require the support of evidence or argument in order for it to be rational” . According to Kelly James Clark, “Reformed Epistemology. . . is eminently defensible” . This view has been held by philosophers such as Alvin Plantinga, William P. Alston, Kelly James Clark, Nicholas Wolterstorff, and many others.
Of course, Reformed Epistemology goes much more deeper than the mere face of it. As we will see through the writings and thought of philosopher Alvin Plantinga, our belief in God may be what is known as “properly basic”, and that is the attention I want to give throughout this post.
Plantinga’s Religious Epistemology
It is important to understand Plantinga’s distinguishing of warranted and justified beliefs before expounding on his religious epistemology. In his Warrant and Proper Function (hereafter, WPF) Plantinga “develops a comprehensive account of the epistemic virtue that when added to true belief yields knowledge – namely, warrant” . This is where Plantinga parts with a given philosophical tradition who defined knowledge either explicitly or implicitly in terms of justification. Thus, warrant and justification became two completely different and distinct epistemic properties. The former, warranted belief, is a property of beliefs whereas the latter is a property for persons.
Thus, the conditions for some given warranted belief p for person S is one that meets the following four conditions:
- p is produced in S by properly functioning cognitive faculties.
- p is formed in an appropriate epistemic environment.
- S’s cognitive faculties are operating according to a design plan reliably aimed at truth.
- S has no defeaters for p.
The discussion regarding warrant and justification was merely here a means to an end; to use James Beilby’s comment, “it provided the epistemological canvas on which to paint his account of religious knowledge” . This account of religious knowledge (or epistemology) is expressed within two models: The A/C Model and the Extended A/C Model. Although the definition of both is rather extensive, I do think something simplified regarding a sufficient understanding is attainable.
The former model is a more general model in application to showing how Christian belief(s) might be warranted, whereas the latter has to deal with our particular epistemic situation (or environment) as Christians. More appropriately stated, the distinctive characteristic of the A/C Model is its “description of the innate tendency for humans to see the hand of God in creation, a tendency that [John] Calvin called the sensus divinitatis” .This “innate tendency” is particularly manifest under given circumstances of awe in creation where an individual has a “sense of the divine” through given experiences while say, listening to a symphony, reading a beautiful poem, and so on.
Plantinga’s Critique of Classical Foundationalism
Plantinga’s religious epistemology rests on a critique of what is known as Classical Foundationalism, a view that has been widely held by various philosophers and is not (or doesn’t seem to be) without compelling reason. Since it would appear to be the case that all of our beliefs cannot be based simply off of other beliefs (since the justification for those beliefs would generate an infinite regress of circularity), there must be some given general beliefs that do not need to be justified by other beliefs. Classical Foundationalism has what are known as basic statements, or beliefs. These are called basic because they have no further need to be justified by anything else. Hence foundationalism only considered two given kinds of basic statement:
- (1) Simple and true statements of mathematics (2 and 2 makes 4) and logic (if p then ~p).
- (2) Statements evident to the senses.
Plantinga has gone so far as to critique this view by including belief in God to be a basic statement – or what he more particularly calls a Properly Basic Belief. A properly basic statement in respect to Plantinga’s understanding of [Classical] foundationalism (which he is against) would be something of the following:
- A proposition p is properly basic for a person S if and only if p is self-evident to S, or incorrigible, or evident to the senses.
Two basic arguments from Plantinga are as follows :
- (a) Properly basic beliefs are not necessarily properly basic by the foundationalist definition (1) given above – nor can they be justified by either deductive or inductive inference from properly basic statements.
- (b) Foundationalists are unable to justify (1) in their own terms; i.e., they have not shown that (1) follows from properly basic statements or is probable relative to these.
Plantinga thence provides an alternative to Classical Foundationalism contending that along with other Reformed thinkers (such as the doctrines found within the thought of John Calvin) that no argument or reason(s) for the existence of God are needed in order to justify belief in the existence of God. Rather, the fact that men have the sensus divinitatis provides the sufficient justification needed to consider God as a properly basic belief. As Michael Martin (1991) clarifies, “The circumstances that trigger the natural tendency to believe in God and to believe certain things about God provide the justifying circumstances for belief” .
Although I am not a Reformed Epistemology advocate myself, I would only critique this view on the grounds that the whole framework is inadequate and incomplete. For instance, Michael Martin (1991) draws upon what I believe to be an important question in respect to Plantinga’s religious epistemology: “How is one to arrive at the criterion of being properly basic?”  Plantinga suggests that the route is “broadly speaking, inductive.” As he writes,
The Christian will of course suppose that belief in God is entirely proper and rational; if he does not accept this belief on the basis of other propositions, he will conclude that it is basic for him and quite properly so. Followers of Russell and Madelyn Murray O’Hare [sic] may disagree; but how is that relevant? Must my criteria, or those of the Christian community, conform to their examples? Surely not. The Christian community is responsible to its set of examples, not to theirs. 
Martin criticizes this view on the grounds that (1) Plantinga’s claim that his proposal would not allow just any belief become a basic belief is misleading. In other words, it is true only relative to the view point of Reformed Epistemologists that not just any belief will become a basic belief. Moreover, (2) the rationality of any belief “is absurdly easy to obtain” . That is to say, that some given cherished belief that is held without reason by any group could be considered properly basic – Martin here is thus drawing upon the inconsistency of Plantinga’s criterion of properly basic beliefs as seen in his critiques (1) and (2).
James K. Beilby (2007) draws upon a considerable evaluation of Plantinga’s “broad foundationalism.” In other words, although Plantinga critiques classical foundationalism and is rather well known for it, he is still nonetheless a foundationalist in the broad or modest sense of the term. While Plantinga contends that “belief in God should be based on a single source of warrant. . . [o]ther sources. . . can contribute to the warrant of Christian belief, but they cannot ground or stand in a basing relationship to it” . Here, Beilby disagrees and makes the notable point that
While it could be (and perhaps occasionally is) the case that Christian beliefs enjoy a single source of warrant, it is difficult to see how Plantinga might support the claim that multiple sources of warrant are logically and theoretically impossible. 
Although these criticisms and more can be considered, I think some questions in respect to the overall coherence of the epistemological model as a whole can be brought into the conversation – regardless where you stand in respect to Plantinga’s position.
-  Kelly James Clark, “Without Evidence or Argument” (1998) quoted from Reason and Responsibility, ed. Joel Feinberg and Russ Schafer-Landau (Thomson and Wadsworth: 2005) p. 111
-  Ibid.
-  James K. Beilby, “Plantinga’s Model of Warranted Christian Belief” in Alvin Plantinga, ed. Deane-Peter Baker (Cambridge University Press: 2007) p. 127
-  Ibid.
-  Ibid., p. 129
-  See Michael Martin, Atheism: A Philosophical Justification (Temple University Press: 1990) p. 268
-  Michael Martin, The Case Against Christianity (Temple University Press: 1991) pp. 28-29
-  Ibid., p. 29
-  Alvin Plantinga, “Religious Belief Without Evidence” in Philosophy of Religion, ed. Pojman, p. 468
-  Michael Martin (1990), p. 272
-  James Beilby (2007), p. 148
-  Ibid.