Apart from the more serious concerns, I find it quaint that both Parsons and Martin apparently hold to the notion that truth is in part determined by the number of pages one writes. Though my opening essay is directed to a non-technical audience, perhaps no such discussion need take many pages given the inability of the non-Christian program to get off the ground. Nevertheless, neither of my interlocutors chose to sketch how their particular epistemological standard might aim to justify knowledge of any sort. I will begin by examining and rejecting Parsons' two primary objections (a remaining concern will be examined under Martin) and then turn to do the same for Martin's four.
Parsons 1: Autonomy is inescapable -- Parsons (1) pleads guilty to epistemological autonomy, "recognizing no higher authority for...judgments about truth, value, etc.," since it is inescapable and (2) argues that a Christian alternative would produce an infinite regress.
(1) Parsons here at least recognizes that some knowledge involves certainty even though he later attempts to deny it; nonetheless, the Christian challenge isn't whether one should ultimately choose between a competent autonomous standard and a subordinate revelation but rather: where is a competent autonomous standard? For example, if Parsons, not being a subjectivist, seeks to determine knowledge by means of an empirical criterion, then he needs to demonstrate how he gets from particular perceptual states ("appearing redly") to general propositions of common experience, logic, mathematics, and values; alternately, if he seeks to determine knowledge by means of some modern Rationalist line ("self-evident", a priori general truths, etc.) and deduce a system of knowledge, then he needs to demonstrate how he gets beyond the most trivial generalities to knowledge of particular facts. Whichever option or variation on these themes the non-Christian takes will end in skepticism, as the history of philosophy demonstrates so aptly. In contrast, the Christian worldview provides the necessary preconditions which make these sorts of knowledge possible.
(2) Parsons' argument threatening an infinite regress rests on a confusion over the nature of ultimate standards. Parsons argues for his ultimate standard by making it self-validating ("nobody...has any choice in the matter"), and Christians argue for theirs in the same way. Neither group could do otherwise. Hence, an infinite regress does not threaten either, but the pressing question is: which view of reality provides the preconditions of knowledge which we all agree that we have? The answer: Christianity.
Parsons 2: Self-defeating futility -- Parsons argues, "finally and fatally," that if the Christian argument regarding the futility of non-Christian categories is sound, then the non-Christian is "justified in dismissing... any argument that guarantees that I cannot rationally accept its conclusion."
First, note that Parsons doesn't follow his own reductio in his objection; on the one hand he claims that he would have no rational criteria available, but then he also claims to be "justified in dismissing" the argument. Which is it? To be more consistent, he should either be philosophically silent or reject the non-Christian principles which led to such an absurd position.
Second, the Christian critique recognizes that Christians can reason with non-Christians only because the latter don't act in accord with their basic principles. Non-Christians can reason, do science, ethics, etc. because they live in a Christian universe which makes these activities possible (as opposed to a non-Christian universe where, for example, materialism precludes universal and necessary logical principles or a eastern monism which obliterates ethical and mathematical distinctions). Moreover, Christians maintain that this sort of "rebellious borrowing" from the Christian view of reality has occurred since the Fall of man, and, hence, would include all non-Christians (including Thales, contrary to Parsons' rather narrow understanding of a Christian God who just pops onto the historical scene during the Roman Empire).
Martin 1: Indirect Arguments -- Martin begins his discussion by offering two indirect arguments against the claim that knowledge presupposes the Christian God: (1) His own arguments (over "eight hundred pages" remember) allegedly demonstrate that (a) traditional arguments have failed, (b) the concept of God is incoherent, and (c) the argument from evil, etc. make God's existence "unlikely," and (2) no great apologist has used this sort of transcendental argument for Christianity.
None of these concerns, however, counts even indirectly against my case, given that (1a) traditional arguments fail in part because they are based on philosophical compromises with self-defeating non-Christian views, (1b) Martin's arguments for the incoherence of the concept of God begs-the-question (see below), and (1c) Martin cannot justifiably distinguish evil from good in order to raise the objection from evil. Finally, Martin's indirect argument (2) regarding the history of apologetics is really more of an autobiographical comment on what Martin has and hasn't read rather than an argument against the view I defend, given the rich development of this sort of Christian outlook in the Scripture, Augustine, Calvin, Dutch Reformed and Princeton/Westminster theology.
Martin 2: Direct Arguments -- Martin's direct objections against a Christian transcendental argument fail because they do not address ultimate epistemological standards but instead focus on lower-level knowledge concerns. Christians obviously hold to some version of fallibilism and human epistemic limitation in regard to most knowledge claims, and so his three arguments miss the target.
Nonetheless, no one is a consistent fallibilist in regard to ultimate standards of knowledge -- claims to certainty at some point are unavoidable. As we've seen, Parsons holds to epistemological autonomy with the utmost certainty, and Martin wants to defend objective standards of knowledge. Nevertheless, unless Martin distinguishes between lower-level knowledge claims and his ultimate objective standards of rationality, then his version of fallibilism will entail epistemological relativism. If "knowledge claims are always subject to revision in the light of new evidence," then Martin's "objective standards," which he defends with such zeal, are really just passing prejudices which will someday be rejected. If he's willing to adopt this sort of consistent Quinean relativism, then perhaps he ought to place disclaimers on his books warning readers that he only intends to offer contemporary logical prejudices.
So, though both Parsons and Martin argue that knowledge does not entail certainty in some Cartesian sense, they are partly right and partly wrong (Parsons' assertions regarding my attempt to resurrect some Cartesian argument is quite off the mark; Descartes used blatantly autonomous and anti-Christian categories, thus leading to skepticism, though it took the likes of Hume to point this out). Parsons and Martin assure us that "unknown factors" do not generally count against lower-level claims; this would just be silly. But, "unknown factors" may count against ultimate standards since we are dealing with universal and certain claims. And this is one place among many, where non-Christians will make sweeping claims to knowledge but cannot deliver what they promise. In short, we should compare the opposing Christian and non-Christian claims to certainty, and choose the one which doesn't vitiate science, logic, history, ethics, language, art, etc.
Finally, on this score, Martin challenges me in regard to the claim that non-Christian philosophies produce, at most, trivial knowledge claims. He insists (1) I haven't argued for this claim or (2) refuted his "long and detailed defense" of the Logical Positivists.
(1) Though I did argue for this claim, the burden is really on non-Christians to defend their own worldview. Though a thorough survey of every non-Christian thinker is not possible, let me, once again, just challenge two strains of non-Christian thought: rationalisms and empiricisms. If Martin is so confident in non-Christian knowledge, then he should show us how we get anything beyond the most general platitudes in rationalism and vacuous perceptual states of empiricism. As Martin himself says, "scientific knowledge is limited but hardly trivial or unsubstantive." Exactly. So how does the consistent empiricist (or modern Logical Positivist) ever get there on the basis of his autonomous standard?
(2) In Atheism: A Philosophical Justification, Martin defends a revised version of verification principle which focuses not on meaning in general but on factual meaning (i.e., a criterion of what sentences express statements) in which meaningful statements are those which are "confirmable or disconfirmable in principle by nonreligious, straightforward, empirical statements." He concludes, not surprisingly, that "religious language is...factually meaningless."
First, how does this formulation not rule out the standards of logic? Has Martin confirmed or disconfirmed the law of non-contradiction and a host of other similar criteria? How would one find an "empirically determinate state of affairs...to count against" the truth of a foundational statement like this? Second, the standard begs-the-question against the Christian in the most egregious fashion: "The very notion of referring assumes some temporal or spatial or spatial-temporal scheme." With that sort of guiding dogma, how could one not be an atheist?
Martin 3: Alleged Inconsistencies -- Martin's third argument against the Christian critique I offer is that it is too general since, he claims, that the "God of the Jews or Islam would also seem to provide the epistemological foundation that Jones wants."
First, Islam vitiates knowledge as much as any non-Christian "secular" philosophy. Though a detailed analysis is beyond the scope of this discussion, the Islamic God is not the God of the Bible, and so we should expect that it undermines knowledge. For example, depending on the version of Islam one focuses on, the general and absolute unity of Allah is so guarded against the imperfections of plurality that Allah cannot be said to know any particular items or facts, including the historical Muhammad. This has long been a vigorous problem in Islamic philosophy/theology. The implication of this and similar problems are many, but Allah in no way provides a transcendental foundation for knowledge as we find in the triune God of Christianity. Beyond this, Christians also rule out Islam on the basis of its gross theological departure from the Old Covenant.
Second, since Christianity in its best form is the most orthodox form of Judaism, i.e., the fulfillment of the Abrahamic Covenant, Christians have no philosophical dispute with a faithful Judaism since the two would ultimately be identical. Nevertheless, until we reach that point, our disputes will be exegetical and only philosophical to the point where Judaism (or Christianity) compromises with non-Christian thought. In short, Martin's arguments again misfire.
Martin 4: Christianity and Subjectivism -- In his most disappointing section, Martin argues that Christianity fails to provide an objective foundation for epistemology given even a "cursory glance at the controversies within the Christian religion." Consider what Martin's reasoning would do to numerous historical disputes in science: As James Rachels has argued, "We cannot conclude that the world is shapeless simply because not everyone agrees what shape it has." Moreover, Martin himself answers opponents of his verification principle who claim that "since some people disagree over whether some examples of putative statements are factually meaningful, one cannot appeal to any examples to support this principle. But this is a non-sequitur." Well said.
In all, neither Parsons nor Martin come close to getting the non-Christian program off the ground. Their criticisms are either irrelevant, beg-the-question, or rest on confusions. They have yet to meet the Christian challenge head-on or justify their own standards of knowledge. As the Apostle Paul declared, we should look to Christ for "all the treasures of wisdom and knowledge."