Reasoning by Presupposition: The Bahnsen-Smith Debate

I was perusing the apologetic blogs a few months back when I came across a comment by an atheist who claimed Christians never refer to the Bahnsen-Smith debate (although that interchange was more a moderated conversation than a debate). Well, that claim is not true. To rebut that claim, here is a link to the audio of that debate. A transcript of the audio can be found here. Another post of the dialog can be found here. This dialog is well worth studying to understand Bahnsen's use of the presuppositional apologetic. Apparently, that atheist thought Smith bested Bahnsen in that encounter. Incredible! Such an opinion, as we will see below, betrays superficiality and an unstudied philosophic naivete. Smith,and a caller-in named Max, clearly had no clue as to what hit them. Bahnsen's irenic answers rebutted all of Smith's claims.

One particular point, that has prompted the title of this article, was when Max charged that Bahnsen merely presupposed God.  Of course, it is not the case that we merely do so (as if, the presupposition of Christianity is a fideistic and unargued assumption). Bahnsen's reply that atheists presuppose atheism was priceless.  This is a perennial blind spot of atheists -- they think they are devoid of presuppositions and are staunch advocates of non-circular reasoning. Nothing could be further from the truth.  Atheists, in fact, argue presupposing atheism (consequently, this atheist's charge against Christians commits the fallacy of special pleading, sometimes called "the double standard fallacy"). However, the fact that both sides have presuppositions does not reduce the debate to a stand off. Not all presuppositions are "created equal." The problem for the atheists is that they have a multitude of unintelligible contradictory assumptions and viciously circular arguments, none of which are mutually coherent, and none which they can make good. This fact renders the atheist's presupposition(s) false and destroys his pretense to knowledge of any sort. This fact is evident in the many debates of presuppositionalists with atheists. Some atheists will even admit (on the basis of their assumptions, of course!) there is no certain knowledge or express doubt that knowledge is possible (not realizing the inherent self contradiction in such claims -- since they must know something in order for their language to intelligibly express their doubt. To put it ironically: "Why should anyone listen to someone who believes he doesn't know what he's saying?") On the other hand, the Christian presupposition is intelligible and provides the necessary grounds for knowledge and for the intelligibility of all of human experience. So again, there is no "stand off."

Here are a few more of the high points in the dialog:

• Max claimed reason is "natural!"  Another priceless moment.  Bahnsen pressed the point that abstract entities are not natural.¹  All Max said by way of "rebuttal" was a repeated "Oh boy!"  Bahnsen challenged atheists to live according to their presuppositions -- something they never do.
• Smith assimilated physical causation and logical laws (logical "law of identity" for instance).  Bahnsen succinctly pointed out that such is a major philosophical error.²  For starters, matter does not move according to abstract laws of rational thought (logic) -- matter obeys inviolable physical laws based on the properties of matter. The material universe is completely oblivious to abstract laws of logic. Laws of logic are standards of rational thought -- laws that can be violated by flawed reasoning.  As we have mentioned repeatedly, laws of logic presuppose minds with rational freedom (independent of material causation) and mental causal efficacy -- something totally antithetical to a universe composed solely of matter moving according to chance and causally inviolable physical laws. (In the materialist universe the only causality is, de facto, physical.) To put it another way, laws of logic are necessary and non-contingent; on the other hand, the physical world is contingent and the laws of physics are not necessary. (If they were, empirical science and experiment would be unnecessary.) This is usually stated succinctly by the phrase "logic says nothing about the contingent world." We should also point out that physicists can construct a multitude of consistent theoretical models of the material universe with existing and hypothetical entities, differing mathematical structures, different causal interactions, different values of fundamental constants, and so on. All of which show that the actual physical reality in which we live is not necessitated by logic. To summarize, logic and physics are categorially distinct. Contra Smith, logic cannot be reduced to physics.
• Smith trotted out the tired and fallacious "Euthyphro dilemma" to counter Christian moral claims.  Bahnsen succinctly rebuffed Smith by pointing out that Christian moral claims are rooted in the character of God Himself.  In Christian theism, God is ne plus ultra³. There is no "super-reality" above God; no laws above God.⁴  

In summary, Bahnsen  began the dialog by engaging Smith on the three fundamental areas of philosophy: (1) What exists? What is real? What are the constituents of reality? (Metaphysics/ontology); (2) How does one know what one knows? (Epistemology) and (3) How should we lead our lives? (Ethics).  Beyond Smith's philosophical naivete and reasoning errors, Smith, like all atheists, did not even begin to provide intelligible answers, based on his godless reality, in any of these areas. Smith's materialist atheism is: (1) metaphysical irrationalism (espousing the ultimate chance nature of reality); (2) provides no self-attesting theory of knowledge (rendering knowledge impossible, and thereby, Smith has no ground from which to criticize anyhthing); and (3) provides no basis for the existence of absolute morality or ethical truth (morality is not a property of material systems).  All through the debate, Smith argued in vicious circles and merely assumed the existence of human rational freedom (which is incompatible with the assumption of material monism), logic, moral laws, abstractions, conceptual reasoning -- all of which inexplicably spring out of chance and physical (material) causation (or, alternatively as in platonistic pluralism, are an incoherent plurality of independent and ultimate brute entities suspended in the "void").  As Bahnsen pointed out, all of these are problems in Smith's atheist universe, but not for Christianity. (In fact, Smith is assuming facts that are borrowed from Christian theism.) Smith's atheist presuppositions thus have been shown to be incoherent and self-contradictory on the atheist's own ground, while the Christian presupposition and Christianity is vindicated.  

Postscript

During the call-in section, Smith responded to a question regarding the Bible. Smith responded, "Well, I mean there are some decent things in the Bible, sure. There are some elegantly expressed moral maxims, that sort of thing." (emph. added.) Bahnsen, probably due to lack of time, didn't respond to this but the reply to this sort of remark is: "On what standard does Smith rely to determine morals?" Would he claim that standard is absolute and knowable? On Smith's view the moral statements of Christ would be no more authoritative than those of any other; merely subjective opinion and non-absolute. The fact that Smith likes some of them is not a basis for absolute morality. Some people like Coke, others Pepsi. Smith, like all unbelievers, is his own ultimate, and arbitrary, standard.

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1 Abstract entities, such as the laws of logic, are immaterial and not extended in space. As, such they are not empirically accessible; they are not natural objects perceived by the senses. For example, the law of deduction called "modus ponens" cannot be seen with the eyes. The question of the reality of abstract entities (especially universal and invariant concepts such as mathematics and logic) and conceptual knowledge lies at the root of the well known failures of rationalism, on the one hand, and empiricism, on the other, to provide a foundation for human knowledge. Both schools ended in skepticism regarding human knowledge. One should also consider that the modern phrase "logical empirical method" merely linguistically conjoins the two philosophical schools and thereby glosses the problems of both without solution, yet admits the distinction between the abstract and the natural. Stated in other terms, this dichotomy is also the distinction of deduction (necessary truths of reason) versus induction (contingent truths derived from generalizations of particular sense data). Bahnsen's point is that the atheist "universe" provides no intelligible account for either reason (human rational autonomy and conscious thought independent of material causation, existence and reality of universal laws of logic, etc.) or empirical knowledge/induction (given the atheist's commitment to ultimate chance and the irrational nature of the universe as embodied in quantum mechanics). On the atheist view, there is no bridging of the gap between the immaterial transcendent and unchanging truths of, say, logic or arithmetic, and the immanent and ever changing world of material flux. The problem that the atheist has with providing a justification of induction is well known -- it is a principle that cannot be deduced nor inductively derived (which is vicious circular reasoning and question begging). On the other hand, the transcendent God of Christian theism provides the intelligible answer to both deduction/reason (man is created in the image of God, the ultimate rational being and the source of man's reason -- behind the mind of man is the mind of the eternal God) and induction (God has created and faithfully sustains the cosmos ("...in Christ all things consist." Colossians 1:16-7). Further the existence of universal abstract entities, in that they are the contents of thought, are not eternal self-existent things existing in a mind-independent platonic world of ideas, but rather, the thoughts of the eternal God. They are real; and man, as the rational image of God, is to "think God's thoughts after Him," as Van Til has said. ^↩
2 Smith fallaciously used the example of the "Law of Identity" as "support" for his claim. Rather than the law of identity, one might think that the material conditional of logic ("if P then Q") would provide a more plausible support. However, it is generally known that the material conditional does not represent the concept of causality. See, for example, Paradoxes of Material Implication (in particular, see the example of switches in a series circuit in the section on "Simplification"), Material Conditional; and Causality (section titled, "Causality contrasted with conditionals"). Incredibly, Rudolph Carnap (a logical positivist) makes the philosophical error of representing causal laws via the material conditional in chapters 1 and 20 of An Introduction to the Philosophy of Science. ^↩
3 Latin, literally,"no more beyond." ^↩
4 Amazingly, Michael Martin also fatuously uses a version of the "Euthyphro dilemma" in his flawed TANG ("Transcendental Argument for the Non-existence of God").  The Euthyphro dilemma presupposes a mythological platonic reality of ultimate abstract moral laws to which all the "gods" and man are equally subject (and of which laws they somehow have knowledge) -- as such, it is contrary to the claim of Christian theism that God is ultimate.  Thus Martin's counter does not apply -- it is a straw man. It is a logical fallacy of the most egregious type to assume the truth of "not A" to refute "A." TANG as a refutation of TAG is an utter failure. TANG is not even analogous to TAG. To be analogous, TANG would need to show: (1) that the Christian conception of God is contradictory and (2) that atheism (whether materialist or platonic pluralism) provides the necessary and coherent conditions for all of human experience -- including intelligible accounts of possibility of knowledge and existence of moral absolutes.  This, of course, is something that neither Martin nor millennia of failed atheist philosophy and science has done.  In short,  TANG is not a transcendental argument and Michael Martin does not understand transcendental argumentation (at least, he fails to understand TAG).  ^↩