On the popular level, the issue of intuitions has been quite contentious. Most people tend to think of intuitions as a kind of “sixth sense,” ESP, or other type of supernatural or unusual insight into certain situations (or types of situations). This has, in some ways, carried over into philosophical debates over epistemology. Because of this, appealing to intuitions in a philosophical debate can be met with derision or incredulity. It is important to understand that I shall be considering “intuitive knowledge” to be a type of knowledge not gained via some process or experience with the world, or even gained from reasoning itself. It is something with which knowers “come to the table;” they must already have it in order to know anything from it at all. In this paper, I will defend the idea that intuitive knowledge is generally reliable, necessary for any knowledge at all, and leads to a kind of foundationalism. I will explain my concept of intuition, construct and apply an argument for foundationalism, consider various objections that can be lodged against this approach, and provide tentative responses. The conclusion will be that foundationalism survives, and intuitive knowledge appears necessary for any knowledge at all. First, we must explain intuition.
The Explanation of Intuition
No account of intuition is complete without a discussion of a basic definition. I am using “intuition” in a very broad sense. This sense covers Richard Swinburne’s use of what it means to be a basic belief. He writes, “Some beliefs are what I shall call ‘rightly basic’—that is, ones that we are justified in holding without their needing other beliefs or other mental states as grounds, in the sense that, intrinsically or merely in virtue of our having them, they are probably true.” In other words, these beliefs are not based on other beliefs; they are not justified by anything outside of themselves.
These beliefs can be called “basic” beliefs. They are called this not only for the aforementioned reason, but also because they can serve as “foundations” for other beliefs that gain their justification from these basic beliefs (these beliefs, incidentally, are referred to as “based” beliefs). Because these basic beliefs are not derived from any others, Plantinga describes them in nearly perceptual terms. He claims, “I simply see that they are true, and accept them.” These intuitions are the building blocks for all other types of knowledge. There are four types of examples of this intuitive knowledge that will be addressed.
First, there is the example of a priori knowledge. An a priori claim or piece of knowledge is something that can be known independently of any empirical truths or investigation of the world. Here, then, we can see the difference between an intuition and an a priori belief: while intuitions are these types of beliefs, a priori is being used as a category or way of knowing; the other areas will include examples of this intuitive knowledge. Some a priori truths are self-evident—that is, once all of the relevant terms are understood, then one comes to see and believe the truth of the entire claim. However, what is behind that claim is intuition. There are a priori claims that are not self-evident (think of complex mathematical equations), but all intuitive claims are self-evident in this way.
Second, there is the example of inferential knowledge. Inferential knowledge is of the form, “If p, then q; p; therefore, q.” Such an argument demonstrates one of the laws of argumentation in logic known as modus ponens. Another example of inferential knowledge concerns mathematical claims: “If 1+1=2 and 2+2=4, then 2+4=6.” Suppose Jim wanted to show that intuitions of the inferential variety were in fact grounded in other beliefs that supported or justified the intuitions in question. How would he go about doing this? In the case of the mathematical belief, perhaps Jim could claim something like the following: 2+2=4 is only true in cases where 1+1=2, so that 1+1=2 serves as a basis for grounding 2+2=4. First, it is unclear that Jim, or anyone else, actually obtains their belief (or maintains it, for that matter) by reasoning in such a manner. Rather, with Plantinga, Jim (and others) simply sees such a belief is the case. Second, Jim has only put the problem off by one step: even if we accept that 2+2=4 is a based belief, that still leaves 1+1=2, and Jim has not justified this belief by way of another. Indeed, it seems he cannot.
Jim is worse off still when it comes to basic laws of reasoning, such as modus ponens or the law of non-contradiction (LNC). With respect to these, Jim will not even be able to appeal to any other beliefs. Suppose he tries to argue that in all cases where modus ponens has been observed in the real world, it is successful. This claim itself will crucially rely both on modus ponens and LNC. If it attempts to jettison the two, then any claim to showing these two will either be subject to contradictions or unable to be used as anything more than an unfounded probabilistic claim. It therefore seems inferential knowledge is a type of intuitive knowledge.
Next, non-inferential knowledge can also be intuitive knowledge. This is not the claim that all non-inferential knowledge is intuitive; that would be demonstrably false. It is simply the claim that there are some types of non-inferential knowledge such that they are intuitive in nature. Consider memory beliefs, for an example. While it is not the case that particular memorial beliefs are intuitive (after all, I remember what I ate for lunch today; the belief of what I had for lunch today is not broadly intuitive), the belief that memorial beliefs are reliable is intuitive. There is no non-circular way to prove that one’s memories are reliable, for virtually every claim one makes will assume that memory works in such a capacity. Intuition, however, does provide such a belief.
The final type of knowledge supported by intuition is modal knowledge. Modal knowledge comes from the idea of modal logic. Harry Gensler explains modal logic as a “logic [that] studies arguments whose validity depends on ‘necessary,’ ‘possible,’ and similar notions.” If something is necessary, then it could not fail to be the case. If something is possible, then it could either be the case or not be the case. While some of modal logic is inferential (that is, the beliefs are derived from other, more fundamental beliefs), what we take to be possible and/or impossible is often the result of our modal intuitions. How we know what seems to be possible to us just is the general intuition at work in our doxastic structures. Now that some examples of intuition have been shown, an argument for foundationalism shall be developed.
An Argument for Foundationalism
The idea of intuition naturally leads to the idea of foundationalism. Robert Audi describes foundationalism by defining it as follows: “[Foundationalism is] the thesis that the structure of a body of justified beliefs is foundational, where this is taken to imply that any indirectly (hence non-foundationally) justified beliefs there are depend on directly (thus in a sense foundationally) justified beliefs.” These directly justified beliefs are intuitive beliefs, as this paper has been using the concept of intuition. The argument for foundationalism will be stated in explicit fashion, and then defended. It is as follows:
1. If there is no relevant intuitive knowledge for p (where p is some proposition), then there is no knowledge of p.
2. There is knowledge of p.
3. Therefore, there is relevant intuitive knowledge for p.
This argument is a successful one for foundationalism because of the word “knowledge” in the premises. Certainly (1) does not require one to commit to the idea that the knowledge of p itself is intuitive (as would be the case if the claim was that knowledge of p just is intuitive knowledge), but rather that p stands in relation to a chain of justification that terminates in an intuition that is sufficient for knowledge. (1) makes a claim of necessity: without a relevant intuition counting as knowledge for p, p cannot be known. This premise will be defended more fully in a later section. For this point, there are three considerations that must be taken into account.
First, this assumes the relevance in the justificatory chain for p of the intuitive knowledge. That is, it will not do any good to have an intuition that seems irrelevant to the transmission of justification to the belief that p. If Jim claims to have an intuition that the sun will rise tomorrow, this particular belief is not relevant to the belief that “All men are mortal.” It may be the case that the two beliefs ultimately share a similar intuition, but then it will be that intuitive belief that is relevant, not the belief that the sun will rise tomorrow (if such a thing can even properly be intuited, rather than inferred from intuitions).
Second, (1) assumes that, while one need not know that he knows that p in order to know p, in order to be justified in believing p, the justification must be itself justified. This does not mean one has to show the justification of what justifies p (for instance, the prior belief q). I am assuming an internalist account of justification (I am not, at this juncture, taking a position with respect to knowledge). Audi explains an internalism about justification as being the state in which one has access to the elements that justify a belief—in this case, those elements being intuition. He defines this internal accessibility as “that to which one has access by introspection and reflection.” For Audi, introspection is examining what is within one’s own consciousness, while reflection is simply rationally considering the truth of some proposition or set of propositions. The knower then has access, and hence, justification, by reflecting on the thoughts of his own consciousness. Therefore, if, upon reflection, some relevant intuition is accessed within Jim’s consciousness, Jim is justified in taking it to be true, absent some defeater.
A question presents itself: even though Jim must be justified in believing p, and the transmission of justification must continue on uninterrupted, does Jim have to know or show what justifies q, if q justifies p? At least when it comes to intuition, it does not seem so. Part of the reason this is the case is due to what is called an epistemic chain. An epistemic chain is something where a belief is justified by another belief, and that belief is justified by a further belief, and so on. There are four possible “ends” to an epistemic chain. The first end is to claim that there really is no end; the epistemic chain goes on infinitely, with an infinite number of beliefs justifying an infinite number of beliefs. The second end is to say that some belief is simply unjustified, and has no reason for which it should be regarded as true. The third end is the foundationalist end, which is to say that the epistemic chain terminates in direct knowledge (that is, a belief which is not justified by any further belief but is justified in itself). The final end is to say that the chain terminates in a “circle . . . [or] web of justification by claiming that P, Q, and R all justify each other in a mutually supporting pattern of interaction.”
Jaakko Hintikka implicitly recognizes these types of responses to epistemic chains. In his work, what he calls “ultimate presuppositions” I call intuitions. Hintikka claims of these intuitions that “They are not answers to any prior questions.” For Hintikka, then, an infinitely long chain of justifications is out, and it terminates with some intuition. Whether that intuition is justified, unjustified, or circular need not be adjudicated with respect to whether or not Jim must trace back his justification by showing how each belief is justified. On any of the other three accounts, Jim may not know what justifies q, even if he knows q justifies p. Consider Jim’s knowledge that the sun will rise tomorrow. He justifies this by the inductive principle. Jim does not know what justifies the inductive principle. Yet it would seem false to say Jim lacks justification for the sun’s rising tomorrow. It therefore follows one does not have to know or show what justifies a belief q that justifies p.
In addition to other assumptions, this premise (1) also assumes something very much like the justified true belief (JTB) account is the correct analysis of knowledge. While I am aware of Gettier cases, it should at least be noted that in the usual sense (especially considering intuition), justification at least appears necessary for knowledge. If JTB is even remotely accurate, then (1) stands a chance at leading us to foundationalism.
Another important point to consider is that intuition is a generally reliable source of knowledge. This is important since if, upon investigation, intuition is generally unreliable (or not reliable at all!), then what we know will be drastically reduced. If intuition is necessary for knowledge, but generally does not deliver true beliefs, then most of our beliefs are false. It may even be that we have a defeater for our beliefs, depending on what the account of intuition and its reliability is. Roderick Chisholm, in defending a Kantian view of the a priori, argues that intuition is generally reliable. By “generally reliable,” I do not mean a kind of enumerative comparison, whereby we see that a high percentage of intuitive beliefs are true, and therefore generally reliable. I mean intuition is a belief-forming process by which we can expect beliefs to be true, in the absence of a defeater. Chisholm wants to defend the idea of the a priori in terms of necessary truth, but it does establish that intuition is a source of belief that is generally reliable (otherwise we could not know the meaning of statements such as “nothing is red and green all over,” or at least not know whether or not such a statement were true). If intuition is the basis of the argument for foundationalism, and if intuition is generally reliable, then this argument must be applied to four areas of knowledge.
The Argument Applied
A good area in which to explore intuitive knowledge is in the area of morality or ethics. Certainly, some ethical knowledge can be inferred (such as “it is wrong to kill unjustifiably; abortion is killing unjustifiably; therefore, abortion is wrong”), but other moral propositions cannot be inferred from “more basic” moral principles. They simply are the basic moral principles, and it can be argued that they are known intuitively. Premise (1) of the foundationalism argument claims if there is no relevant intuitive knowledge for p, then there is no knowledge of p. Within this context, then, if there are no intuitions backing some moral proposition p, then there is no knowledge of that moral proposition p. Chisholm argues that “The philosophical significance of the particular examples we have considered lies partly in this fact: if some of them must be acknowledged as exemplifying the . . . a priori, then, in order to defend skepticism . . . it will not be sufficient merely to point out that some such statements, if they are known to be true, are . . . a priori.”
If moral judgments are taken seriously, then, whichever metaethical theory triumphs, intuition is necessary for these basic moral judgments. In speaking of this, Moreland and Craig remark that there are four areas in which intuitions are needed for moral thinking: specific cases of moral judgment (e.g., “You ought not to lie tomorrow morning to the teacher”); moral rules and principles (e.g., “You should not lie”); normative theories (deontological concerns); philosophical or religious background beliefs. All of these rely crucially on intuition and could not be justified, and hence not known, otherwise.
The next area to which intuition shall be applied is in the area of scientific knowledge. It is clear that scientific advancements have been extremely beneficial in the pragmatic areas of life. In the theoretical and intellectual areas of life, scientific endeavors have made great strides. Could this really be possible without intuitions? Popularly, many defenders of science think so. This, however, is not possible. Consider the words of Immanuel Kant: “It is possible to show that pure a priori principles are indispensable for the possibility of experience . . . For whence could experience derive its certainty, if all the rules, according to which it proceeds, were always themselves empirical?”
The idea is that if science attempts to justify itself, then there is an insurmountable problem with justification. In order to use the inductive principles that are at work (the uniformity of nature, the principle of parsimony, etc.), the scientist cannot attempt to prove them by the scientific method (or methods). If he does, he will be engaging in circular reasoning; he will be using induction to prove induction. Many scientists are not deterred from their work by this knowledge, but that is because there is a very strong intuition that allows us to know that these basic principles are true. This is what Kant means when he writes, “Such rules could hardly be regarded as first principles.” For Kant, the particular empirical procedures were guided by intuitions that could not be shown, in some cases, at all.
The third area for which intuition is necessary is the area of perceptual knowledge. Perceptual knowledge refers to knowledge gained from the five senses. Audi argues that perceptual beliefs have the property of justification independently of any process through which they might be justified. What he refers to as “prima facie justification” is simply the kind of justification whereby it is rational to hold such a belief in the absence of defeaters; this is the type of justification Audi grants to perceptual beliefs. Why is it important that such beliefs be supported in such a way?
First, if they are to be supported, they will be supported in a circular way. This assumes that a justification will be given that does not appeal to intuitions of any kind. If one wants to show perception to be reliable, he could try to argue that we have evidence that perception yields true beliefs in a generally reliable way, and thereby infer on that basis that perceptual beliefs are justified. Aside from relying on intuitions concerning induction, there is a further problem. The evidence gained for perceptual beliefs is itself gained by perceptual belief. A group of scientists see such reports that perception is successful; they hear such reports at a conference; they experience such-and-such an experiment. All of these ways of verifying perception are themselves perceptual beliefs, and so cannot be non-circularly counted toward the justification of perceptual beliefs. However, belief in the basicality of perception is justified. Again, Audi writes on this subject: “There is apparently no good reason to doubt that these perceptual beliefs are commonly justified.” That kind of justification can only come from intuitions.
The final area for which intuitions are necessary is reasoning itself. While Nicholas Rescher certainly has different intuitions about knowledge than I have, he nonetheless maintains that intuitions drive the justification of basic beliefs. For an example, take the famous syllogism, “All men are mortal; Socrates is a man; therefore, Socrates is mortal.” In virtue of what is this syllogism, taken as a whole, justified? Certainly we could find justification for the individual premises. But what justifies the inference? The only intelligible response we can give is that it just seems to us to be the case that such an inference is correct, and, indeed, could not be false. If this intuition were to be removed, there would be nothing supporting reason itself—at least, nothing non-circularly. This means basic intuition is necessary for justification of reason. Since the argument has now been made, and applied, some objections ought to be considered.
Although many individual objections could be lodged against the argument for foundationalism, or against intuitions, only four shall be considered. There will be objections from skepticism, moral non-realism, Coherentism, and Arationalism. After these objections are presented, some responses shall be given.
There are really two varieties of skepticism being discussed: global skepticism and foundational skepticism. Global skepticism is the idea that if a skeptical hypothesis can be posed for p, then one does not have knowledge of p. There is a skeptical hypothesis for p. Therefore, one does not have knowledge of p. This works for most, if not all, propositions p. A skeptical hypothesis is any logically possible scenario that cannot be ruled out against p. Audi explains it as being an issue of fallibility: if someone could possibly be mistaken about p, then there is a skeptical hypothesis for p; if there is a skeptical hypothesis for p, then one does not know p. Certainty is required in order to ensure knowledge. Foundational skepticism is that while certain things can be known (or at least not ruled out by skeptical hypotheses), nonetheless no one can be justified in taking these things as pieces of knowledge. In either case, intuitions as the terminal link in an epistemic chain are ruled out by skepticism.
Moral Non-Realism/Cultural Relativism
One of the evidences this paper considered for intuition was in the area of moral intuitions. There are two ways a skeptic can respond to these types of intuitions. First, he can deny that there are any moral truths. If there simply are no moral truths, then intuitions are not getting at the truth of the matter. This would be what I mean by “moral non-realism.” Moreland and Craig point out this means a non-realist denies that, “moral statements have ontological implications.”
The second way to avoid these moral intuitions is to claim a kind of cultural relativism (CR). CR maintains that what is right or morally obligatory will be different from culture to culture. If CR is true, and one’s moral intuitions tell him that X is morally obligatory, and if another culture does not perceive this obligation, then it undercuts that our moral intuitions really are getting at the matter. If that is the case, then premise (1) of the argument for foundationalism can be regarded as false.
Perhaps the most powerful objections to the argument for foundationalism come from Coherentism. Laurence BonJour attempts to take the foundationalists’ critique and use it against them. Essentially, the idea is that a basic belief (or intuitive belief) constitutes a good reason in itself to accept a further empirical belief. From this, an argument can be developed such that a belief which is putatively basic is accepted because beliefs of the basic kind are highly likely to be true. But that second condition is itself an empirical belief. BonJour concludes, “We get the disturbing result that B [the belief] is not basic after all.” Additionally, he argues that in order to be justified in holding a belief, the person must possess that reason. If this is true, an anti-foundationalist conclusion will follow.
The final objection to be considered is what I call “Arationalism.” The idea is that the rationality that supports the foundationalist argument is not actually rational, after all. Two major proponents shall be considered. First, there is A.J. Ayer. Ayer thought it was absolutely pointless to attempt intuition, as it committed one to a metaphysic, as well as being entirely a backward epistemology. He queried, “Must he not begin, as other men do, with the evidence of his senses?” While he does grant that the reply concerns intuition, Ayer thinks that this too can be dispensed with. For him, it is the criterion of verifiability, which he states here as saying a proposition is meaningful if “he knows how to verify the proposition.” Since intuitions themselves cannot be verified (and certainly not in the empiricist sense Ayer wants), foundationalism must fail.
Next, there is David Hume. Hume’s argument is even more severe than Ayer’s. He argues that reason itself is not to be trusted. This is because even our process of reasoning is fallible and not true rationality, as we have thought. Instead, Hume thought that reason was forced by nature. “Nature, by an absolute and uncontroulable necessity has determin’d us to judge.” In his mind, then, any attempt to refute this was just an exercise of nature, and so held no more force than anything else. In effect, reason was arational. If that is the case, again, foundationalism cannot be true.
Each of the four major objection categories will have responses. These responses are not intended to be comprehensive; indeed, much could be written on each objection alone. Instead, this section is intended to show how a foundationalist would respond to the various objections. First, it might be thought that global skepticism (or the second type of skepticism) is self-defeating. This is because it seems that there really is a skeptical hypothesis available for the principle that if one is fallible, he does not know p. Perhaps an evil demon is stimulating one’s faculty of reason in just this instance. If this skeptical hypothesis cannot be ruled out, then the conditional can be said not to be known. If that is true, then there is no reason to hold the skeptical claim.
William Alston has further argued that it is not really possible to go through life without affirming some statements as true (any affirmation is a rejection of global skepticism, at the least). Further, this results in what Alston calls “undue partiality,” whereby we are skeptical of some beliefs in an absolute way but not others, and for literally no reason. If this is true, he has further undermined the skeptical conditional.
With respect to the argument from moral non-realism, no definitive argument has been advanced such that we should think our intuitions regarding morality are false. Moreover, this is subject to what I call the Interconnectedness Response (IR). IR states that any use of reasoning against moral intuitions will rely on intuitions, so that this actually proves what it seeks to undermine (in the larger sense). In addressing CR, Harry Gensler suggests that, on CR, the good is what is socially approved, and society cannot be mistaken about what is socially approved. If that is so, then it follows that no moral progress is possible. But it seems there has been moral progress. It therefore follows that CR is false.
As to Coherentism, there are at least two things to be said against that. First, Alston argues cogently for the idea that coherence is not sufficient for truth. This is because there is a large number of sets of propositions or beliefs that are logically incompatible with each other with respect to the truth, but which are all internally coherent. If this is the case, it carries with it the unhappy result that each of these exclusive sets of beliefs are justified in the appropriate way. Second, BonJour’s first argument against foundationalism misses the mark. One does not take the intuition and say, “In a majority of cases, these intuitive beliefs have been correct.” Instead, one finds himself believing the intuition. Alston describes this as belief in an immediately justified way. Next, even BonJour himself has essentially given up his argument that in order to be justified in believing p, one must have the reasons for being justified in believing p. He now writes, “They do not require or involve a distinct second-order mental act with the propositional content that I have the belief in question . . . There is no comparable issue of justification that arises for the intrinsic awareness of this content.” As such, these challenges are overcome.
Finally, the arational objections shall be considered. First, Ayer’s principle of verification is self-defeating. Despite Ayer’s objections, this principle does seem to go beyond the limits that he has set. If the verifiability criterion is true, then it must be shown from the five senses and the physical world. Unfortunately, this criterion cannot be shown from the empirical method. As such, if it is true, it should be regarded as false; this renders it self-defeating.
Next, the lesson Hume derives from his determination of nature argument does not show what he thinks it does. For a refresher, Hume believed that nature fully determined the reasoning process of man, and as such, it was not rational. But it seems Hume’s declaration of this argument is, or at least is supposed to be in some sense, rational. Therefore, it seems Hume’s discussion is really a virtual reductio ad absurdum against arationality. If that is the case, foundationalism still stands.
In this paper, I first explained what was meant by the broad sense of intuition. Then, I used this intuition in an argument for foundationalism. This argument was: “If there is no relevant intuitive knowledge for p, then there is no knowledge of p; there is knowledge of p; therefore, there is relevant intuitive knowledge for p.” I then applied the argument to show that intuition is necessary for moral, scientific, perceptual, and rational knowledge. Intuition is also generally reliable in the sense that it is a rational belief-forming process. Some objections were considered form skepticism, cultural relativism, Coherentism, and Arationalism. Finally, responses were given to undercut or rebut these objections. It seems that intuitive knowledge is generally reliable, necessary for any knowledge at all, and leads to a kind of foundationalism.
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 Richard Swinburne, Epistemic Justification (New York: Oxford, 2001), 26. Swinburne takes “rightly” basic as slightly different than he takes Alvin Plantinga’s “properly” basic (cf. n. 20); this distinction does not affect the argument of this paper.
 Alvin Plantinga, Warranted Christian Belief (New York: Oxford, 2000), 83.
 J.P. Moreland and William Lane Craig, Philosophical Foundations for a Christian Worldview (Downers Grove, IL: IVP Academic, 2003), 85.
 The LNC is not necessary to this portion of the argument. If there are literally any laws of logic, they must function as intuitive bits of knowledge and cannot be further non-circularly justified.
 Swinburne, 26.
 Harry J. Gensler, Introduction to Logic, 2nd ed. (New York: Routledge, 2010), 228.
 Robert Audi, Epistemology, 3rd ed (New York: Routledge, 2011), 216. Audi also lists a theory of knowledge along these same lines, but I am here emphasizing the justificatory aspect. This is because justification is plausibly a necessary condition for knowledge, and the argument I employ will rely heavily on the transmission of justification.
 Ibid., 272.
 Ibid., 273.
 Moreland and Craig, 111.
 Jaakko Hintikka, Socratic Epistemology (New York: Cambridge, 2007), 84.
 Roderick Chisholm, “Reason and the A Priori,” in Readings in Epistemology, ed. Jack S. Crumley II (Mountain View, CA: Mayfield, 1999), 549.
 Ibid., 551-52.
 Moreland and Craig, 422.
 Immanuel Kant, “Critique of Pure Reason,” in Readings in Epistemology, ed. Jack S. Crumley II (Mountain View, CA: Mayfield, 1999), 529-30.
 Ibid., 530.
 Audi, 2. Audi does not argue here that perceptual belief is a basic source of belief, but he does elsewhere.
 Ibid., 28.
 Ibid., 31.
 Nicholas Rescher, Epistemology (Albany, NY: State University of New York, 2003), 7.
 Audi, 338.
 Moreland and Craig, 398.
 Ibid., 409.
 Laurence BonJour, “The Structure of Empirical Knowledge,” in Epistemology: Contemporary Readings, ed. Michael Huemer (New York: Routledge, 2002), 388.
 Ibid., 389.
 A. J. Ayer, “The Elimination of Metaphysics,” in Epistemology: Contemporary Readings, ed. Michael Huemer (New York: Routledge, 2002), 166.
 David Hume, “Of Scepticism with Regard to Reason,” in Epistemology: Contemporary Readings, ed. Michael Huemer (New York: Routledge, 2002), 272.
 William Alston, Beyond Justification (Ithaca, NY: Cornell, 2005), 223.
 Gensler, 40-41.
 Alston, 236.
 William Alston, “Has Foundationalism Been Refuted?” in Epistemology: Contemporary Readings, ed. Michael Huemer (New York: Routledge, 2002), 404.
 Laurence BonJour and Ernest Sosa, Epistemic Justification (Malden, MA: Blackwell, 2003), 62-63.