I recently had opportunity to enjoy breakfast with Bill Vallicella and few other gentlemen who love the philosophical pursuit of truth, beauty, and goodness. Bill is an accomplished philosopher and has an award-winning blog called Maverick Philosopher. There a number of topics on Bill’s blog that are too sophisticated for me to intelligently comment upon (e.g., his interaction with Peter Van Inwagen's theory of properties) . However, I spent some time looking around and found some thoughts that Bill posted on Romans 1.18-20 (Is There Any Excuse for Unbelief?) and I thought I might interact with this post and offer a few thoughts.
1. Bill is a theist who is “sympathetic to Christianity.” His view of the apostle Paul does not appear to be so sympathetic. He argues that Paul begs the question in this passage. He also alleges that Paul appears to be resorting “to ad hominem attacks and psychologizing.” As a conservative evangelical Christian my view of the apostle’s argument in Romans 1 is that it is divine revelation and as such carries divine authority. Mark Thompson argues:
It is Paul’s apostolic commission which sets his epistles apart from other letters in the first century. As letters of an apostle, indeed the apostle to the nations, they are placed alongside the other apostolic documents and continue to exercise a unique and normative role in the church of Jesus Christ. The Pauline epistles should not be viewed as simply as some of the earliest ‘unchallengeable instances’ of gospel-speaking. In and through their undoubted particularity the risen Christ continues to address his people.
I have posted some additional pieces of Mark Thompson’s important essay “The Missionary Apostle and Modern Systematic Affirmation” (HERE) which argue this point more fully. It appears, then, that Bill and I have different methodological starting points as we approach Romans 1.
2. Bill recognizes a potential objection to his reasoning on Romans 1 and so offers a brief rebuttal to the charge that he has not taken into consideration the noetic consequences of original sin. He offers two considerations. The first revolves around the issue of moral responsibility for a sin that “one has not oneself committed but has somehow inherited.” This is a standard objection to the doctrine of original sin and I’m going to let it go for now. The literature on this issue is immense and the back-and-forth charges and counter-charges regarding original sin won’t be summed up here. (I would, however, recommend Paul Copan's essay Original Sin and Christian Philosophy as a good introduction to the topic.) The second objection offered is more easily defused. This objection reads:
Second, if our faculties have been so corrupted by original sin that we can no longer reliably distinguish between the evident and the non-evident, then this corruption will extend to all our cognitive operations including Paul's theological reasoning, which we therefore should not trust either.
Bill has made a hasty move here. The answer to this objection should be evident once the rest of Paul’s theology is taken into account. Yes, our noetic faculties have been corrupted by sin and this corruption does extend to all our cognitive operations but this corruption can (and is) overcome by God’s grace. This is the claim that Paul makes for himself and has been affirmed by the history of the church. Paul has been the recipient of God’s grace and has been commissioned by the risen Christ to bring God’s word to the nations (Romans 15.15-16; 1 Corinthians 3.10; Galatians 1.15-16; 2.9; Ephesians 3.2, 7-8). Once this larger perspective of Paul’s theology is recognized the potential for self-referential incoherence is overcome.
3. Bill states:
But is the world a divine creation? This is the question, and the answer is not obvious. That the natural world is a divine artifact is not evident to the senses, or to the heart, or to reason. Of course, one can argue for the existence of God from the existence and order of the natural world.
There is an alternative way of understanding Paul’s comments in Romans 1. I understand the text of Romans 1.18ff as teaching that unbelievers do indeed know God (in some sense). There is a debate as to whether this passage is teaching that God is knowable or whether he is known. In other words, is Paul teaching that people can reason to God through empirical means or is it the case that God’s existence is apprehended immediately through the natural order? One author put it this way:
Two features of 1:19 are relevant to this discussion. The first of these concerns the meaning of the phrase τὀ γνωστὀν τοῦ θεοῦ. Does this phrase refer to actual or merely potential knowledge? In other words, is there a real sense in which unsaved men know God, or is Paul simply saying that God is ‘knowable’? This second view has the support of many well-known scholars. However, H. G. Liddon’s statement is hard to disprove: ‘The phrase…must, according to the invariable New Testament and LXX use, mean that which is known not that which may be known about God.’... While γνωστὀς may have a potential meaning in Classical Greek, it seems best in light of both NT usage and the context to understand it as a reference to a real yet suppressed knowledge. There is no warrant here to speak of a potential knowledge of God to be gained by probability argumentation. Paul is certainly not attempting a ‘cosmological argument.’ Rather, he is speaking of an actual knowledge of God obtained from nature.
Now may it may be possible to argue for the existence of God by using a discursive process that has its foundation in the natural order but this is not what Paul is doing in Romans 1. Paul seems to be claiming that all people “know” the true God in some sense. Specifying exactly how this knowledge is to be construed is difficult. Reformed theologian Greg Bahnsen has attempted to articulate a philosophically nuanced perspective on the knowledge of God held by the unbeliever in light of the teaching in Romans 1.
When we say that men “know” that the living and true God exists, we are (in part) asserting that they “have evidence” that justifies the belief that He exists. A word should be added here about the general nature of the warrant for believing, to which we implicitly allude in claiming that all men know God.
We do so because of a common but simplistic (and thus misleading) tendency to make inferential or discursive knowledge the model for all cases of knowing. If Sam knows that milk gives him indigestion, he came to this conclusion through certain “steps of reasoning.” He recalled a number of past experiences in which ingestion followed his drinking of milk, but could not remember any cases of ingestion where milk had not been in his diet, so he made a general association and interpreted it in a casual fashion, etc. Sam did not simply look at milk and immediately apprehend it ingestion-producing quality (although some children claim to have this kind of intuitive ability when they encounter new vegetables); rather, he inferred the truth from his experience. Likewise, if Sam knows that 487 multiplied by 139 equals 67,693, it would be highly unusual if he did not gain this knowledge by making a mathematical computation. In a large number of cases, our knowledge of a proposition is warranted by a discursive process of inference. For example, all of the union truckers are on strike; Sam is a union trucker; therefore, Sam must be on strike. Such inferential or discursive knowledge is common, but that does not mean that knowledge arises only from such reasoning. There are obvious cases of noninferential knowledge; it is implausible and artificial to insist that they must somehow be the product of an “unconscious” inference.
Surely there are times when one believes certain propositions with good reason, without inferring them from other propositions—as when one believes that one is typing with both hands, or believes that the music is painfully loud, or believes that one is not the same person as one’s neighbor, or believes the times tables in math. When Sam knows that a black cat is in path, he does not infer it from propositions about his sensations, about forms of appearance, about animal categories, etc. His knowledge is not discursive, following certain steps of reasoning to a likely conclusion; he immediately (without mediating lines of inference) apprehends the truth that a black cat is in his path. (We need not concern ourselves here with debates over how to account for such noninferential cognition, whether by linguistic conventionalism, behaviorism, an intuitive faculty, etc.). Such a non-propositional experience (an acquaintance with an object) is not something mystical and ineffable; rather, people have the ability to express and define the experience propositionally (thus describing it and relating it to other beliefs so that it is available for reference, memory, assertion, inference, application, etc.). The “immediate” apprehension may very well be caused (“mediated”) by natural factors, but the recognition takes place in the absence of discursive inference (drawing a conclusion through the mediation of reasoning from premises).
When we encounter a person at the store and “know” that he is our friend Sam, our belief can indeed be warranted without being derived or reached by a series of mental arguments, computations, or inferences. The same is true when we directly identify his signature on a letter. There is evidence that justifies what we believe, but it is noninferential and direct. This claim should not be too controversial, but it does require some attenuation. In those cases where “knowing” is immediate or noninferential, we are speaking of the evidence as it is apprehended by a particular individual at the initial time of assenting to the proposition warranted by it. No doubt somebody else who is unfamiliar with Sam might not immediately apprehend that this letter is from Sam. And if someone should raise some doubt whether the letter is, after all, from Sam, the kind of “evidence” that would be brought forth to defend or vindicate the challenged belief would be the discursive or inferential kind, rather than the initial evidence of direct apprehension.
Bahnsen, following his theological mentor Cornelius Van Til, goes on to apply these basic epistemological principles to Romans 1 and the knowledge of God.
Van Til maintained, following the teaching of Paul in Romans 1-2, that all men have a knowledge of God that is justified by direct apprehension of His handiwork in the world and within themselves. Even without a discursive argument or a chain of inferences from elementary observations about experience, all men see and recognize the signature of their Creator in the world that He created and controls, as well as in themselves as His created image… This knowledge of God is mediated in the sense of being caused by the stimulus of the external world and man’s internal constitution, but it is apprehended immediately without argumentation, computation, or self-conscious reasoning.
It is important to affirm that this reality of the unbeliever’s knowledge of God is a revealed truth. It is not a truth that is drawn from empirically questioning the unbeliever. Bahnsen recognizes that unbelievers will claim they have no such knowledge. According to Bahnsen’s understanding the unbeliever is in a complex epistemic state in which he both knows God and also engages in a process of self-deception.
With these elements of the complex situation at hand, we can adequately resolve the paradox of saying that the unbeliever believes or (by extension) that the man who does not know God knows God. We will take Sam as our hypothetical unbeliever. When we say that Sam does not believe in (or know) God, we are describing him according to certain features of his behavior and thinking: for example, his immoral conduct and attitudes, his refusal to glorify God, and especially his profession not to believe in God. After all, Sam acts and talks like a person who sincerely disbelieves; indeed, he argues vehemently against believing in God’s existence. However, the fact of the matter is that Sam actually does believe in God. When we say that he believes in God, we are (in accordance with the diagnosis of God’s word) describing him according to certain features of his behavior and thinking that manifest belief: for example, his living in terms of some kind of moral standards, his acceptance of the need for logical consistency, his expectation of uniformity in nature, his fear of death, and his assuming of freedom of thought. As in the case of believers, we say that Sam knows God in the sense that he has justified, true beliefs about Him. So then, it turns out that Sam’s belief is mistaken.
4. Even if one is not convinced by Bahnsen’s analysis there is still something to be appreciated. By taking Paul’s thought in Romans chapter 1 as a revelational set point and attempting to reason from this point allows one to explore epistemological options that may not have been immediately evident. Bahnsen’s conceptualization of the epistemological situation does precisely this without the quick dismissal of Paul’s thought as being engaged in “ad hominem psychologizing.”
 David L. Turner, “Cornelius Van Til and Romans 1:18-21: A Study in the Epistemology of Presuppositional Apologetics” Grace Theological Journal 2 (1981), 53. Online: http://faculty.gordon.edu/hu/bi/ted_hildebrandt/NTeSources/NTArticles/GTJ-NT/Turner-Rom1-GTJ-81.pdf.