Authored by: Mitchell LeBlanc.

I have recently authored two important papers that are integral to my criticism of the TAG and presuppositionalism. The first is my paper entitled, “The Transcendental Argument for the Existence of God.” My second is a recent post outlining the conventionalist justification of logic entitled, “A Conventionalist Justification of Logic.” A presuppositionalist by the name of Joshua Olson has offered various criticisms. Our most recent discussion took place on Facebook and so in this article I wish to simply provide a transcript of that discussion.

The Discussion

Posts by myself will be colored in blue while Olson’s will be colored in green. I will only be modifying the conversation to correct spelling and grammar. Any comments I make will be indicated within the quotation by “[...]”

My initial comment was on a Facebook post by Olson in which he linked a video of Greg Bahnsen offering a criticism of Naturalism.

Mitch:

That’s quite a primitive understanding of naturalism as related to cognitive activity. The best argument of this type is Plantinga’s EAAN. Bahnsen is employing the same fallacy as Craig does when speaking about morality, that is, human beings are animals therefore human beings are JUST animals. By this same token, the physicalist might assert that brain states or chemical reactions but it does not follow that they are then JUST chemical reactions.

Joshua:

I thought you would comment on this one. But how do you account for the logic you used to determine that a fallacy was committed? That is, how do you account for it from within your world view?

Mitch:

We’ve already talked about this… in fact, I’ll post something on UrbanPhilosophy later tonight that outlines precisely how logic is justified without reference to God [this is the previously linked paper on conventionalism]… of course the paper I submitted already showed that your position is logically impossible.

Joshua:

Like I said before, you are arguing against a straw man. The explanation you offered in your paper fails to account for the preconditions of intelligibility.

You are simply making an attempt at showing how an atheistic/evolutionary world view accounts for the preconditions of intelligibility, but the fact that these preconditions exist demands that the Christian world view be true.

But anyway, I will be happy to look over your new article. And if its alright with you I’d like to submit it to a few people I know for further critique…

Mitch:

I’m not really sure why what I’ve said continually regarding this matter is going ignored. You can simply take the argument and run a reductio through your own worldview! The argument, if sound, will be sound regardless of which worldview it is uttered from. If the conclusion of the arguments truly are that the Christian worldview cannot account for logic, then that obtains even in your own worldview rendering it incoherent from the inside. You can’t simply beg the question in favor of your own worldview, not when faced with the conclusion of my argument.

The conclusion of your argument is based on your ignorance of the very foundation for the Christian world view. There were certain aspects of the Christian world view that you simply ignored, and the ones that you documented were misrepresented. Now, if its that important to you, I will go ahead and sift through your article one paragraph at a time. and comment on the ones that are faulty.The issue I have with doing this is simply the fact that you wouldn’t rethink your world view regardless of my counter arguments. You will simply formulate another strawman to argue against. But anyway, I will send you a copy of my review within a few days.

Conventionalism? I suppose I should have stopped reading when I saw the word “truthhood,” but nevertheless, Mitchell, aside from the question begging contained within the article, why ought anyone absolutely be logical?

I’m sorry Sye but you’re not going to get away with that so easily, where is the question-begging?

Well, you’re begging the question that an evolutionary world view can even account for the recognition of logical absolutes. If evolution is in fact true, there is no real foundation by which we deem our senses to be ultimately reliable and we therefore can’t really be sure that we know the truth about anything, at least not in an absolute sense. This reliability of our senses is also presupposed but not accounted for in the atheistic/ evolutionary world view.

You’re not giving the TAG anymore, you’re giving a form of EAAN which is largely besides the point. Conventionalism need not be embraced solely on an evolutionary basis, it would hold if evolution were false.

Well, the only alternative to evolution is creation, so if evolution were false and your argument holds despite the theistic world view or the atheistic world view, then what’s the point of making the argument?

The point is that even if intelligent design is true this does not immediately lead to Christian Theism. It certainly does not satisfy the criteria laid out by that TAG, that Christian theism be the ONLY worldview which accounts for logic. Our discussion shouldn’t be focused on evolution vs. Christianity since the real issue here is the coherence of conventionalism. One only needs that conventionalism be possibly true and the TAG, as formulated by Bahnsen, fails.

Sure, but I think you’re missing my point. That being that if evolution were true, and that natural/material realities are all that exist, we can have no ultimate standard for truth, nor would we have any real reason to adopt an ultimate standard so that truth can be known. Afterall, how can a system of complex chemical reactions really know anything?So, with that said, if you are in fact consistent within your atheistic world view, you should understand that you are limited to naturalism, which renders you utterly incapable of making any claims on the metaphysical aspects of life since those claims are by nature outside the scope of naturalistic explanation, and therefore outside of your world view (at least not without borrowing from Christian principles, which is what you are guilty of doing.)

If you really want to subject your article to tough scrutiny I would suggest submitting to Dr. Jason Lisle at Answers in Genesis or Matt Slick from carm.org.

You’re committing the same fallacy I outlined earlier, just because X is Y it does not follow that X is ONLY Y. Again you bring in this idea of “ultimate standard of truth” but I’ve just outlined an entire system that shows your conception to be in error. Your question “how can a system of complex chemical reactions really know anything?” is not an argument against complex chemical reactions knowing things.I am also not restricted to naturalism as an atheist, that is clearly false. People can be (and in fact are) atheists without being naturalists, namely, there are mind/body dualists who are atheists! Why should I accept your dichotomy as being true? Of course, if I were a naturalist you’d have to show that there are even “metaphysical aspects of life” that I should even care about, otherwise you’re just begging the question against the naturalist.

I have already attempted to speak with Slick but received no response (and his version of TAG is subject to even more problems than Bahnsen’s). I’ve also read Lisle’s book and he is clearly no philosopher, when he talks about epistemology I feel as I imagine many theists feel when Dawkins talks about religion.

Now let’s not diverge from the issue here Joshua, it’s a very simple one. The TAG asserts that no non-Christian theistic system can possibly account for the laws of logic. I have presented a version of conventionalism to which you have not objected to directly. You’ve attempted to invoke a form of the EAAN, but to maintain the coherence of your argument you need my position to be NECESSARILY false (that is, not even POSSIBLY true). The EAAN, even if it succeeded, would not provide you with this! You might show that I have no reason to accept conventionalism (though I don’t think you would), but that is clearly not the same as showing that conventionalism is incoherent. So what you must do, it seems, is find some incoherence in the system of conventionalism I’ve outlined or as you presuppositionalists say, “subject it to an internal critique.”

Until then, even though I don’t think it was necessary to provide, I’ve given you a justification for the laws of logic that does not depend on the Christian God. Now, with this system (again, even though it was not necessary), you can go back and review the articles in my paper. If they are sound, which I’m entitled to think until you show otherwise, not only does your system NOT account for the laws of logic, it CANNOT. So why shouldn’t I just say that it is you who are borrowing from my system?

Answer me this: Is it or is it not true that you must presuppose the reliability of your senses in order to make an argument about anything, or even to recognize and implement logical laws for that matter? If you agree that the reliability of your senses must be presupposed, could you explain why and how these presuppositions are justified from within the atheistic world view, and thereby establishing that your argument for conventionalism is rational to begin with?

Senses and the reliability thereof have absolutely nothing to do with the conventionalist justification of logic. The justification is not a posteriori, why do you think this is? I’ve outlined precisely how conventionalism is explained so I don’t see where you got this idea from.Also, again, the reliability of my cognitive faculties is not the issue here. That is – if we pursue that avenue instead of the TAG, it seems that you are implicitly conceding that the TAG fails to establish its conclusion and that you now have to attempt to undermine my epistemic reliability.

Nope, I believe you’re ducking the questions, just as I thought you would. The point is this, if you cannot account for the reliability of your senses (which you presuppose), you don’t really know the truth about anything, much less the rationality of your argument for conventionalism.The reliability of your senses is another precondition of intelligibility that simply must be assumed in the atheistic world view, but cannot be accounted for, so since it’s just an assumption, how do you know that you really know the things that you know? So, whether you realize it or not, my questions are very relevant to your argument, and also to your position itself, not directly, but they are relevant none the less.You see, a good world view is internally consistent, a rational world view must be able to account for the preconditions of intelligibility, including the reliability of your senses. As for your argument, I’ve already submitted your articles to Dr. Lisle for further review. I’ll let you know if I get a response.

I’ve not ducked your question, I’ve answered it. You’re attempting to shift the goalposts, we WERE discussing the justification for logic but now you want discuss the reliability of senses. Firstly, It is NOT true that I must presuppose the reliability of my senses before conventionalism can be justified. That is to say, the justification of conventionalism is an a priori justification (no senses involved). And again, the point that I seem to have to keep repeating is that if conventionalism possibly accounts for the laws of logic (you have to show that it can’t!) then the TAG fails. It’s really that simple.I am actually surprised that given my article on conventionalism you would ask something like: “Is it or is it not true that you must presuppose the reliability of your senses in order… to recognize and implement logical laws…” That seems to me to have a rather obvious answer.

On the matter of reliability, if you’re going to ask what constitutes knowledge then you really should define what you mean when you say ‘knowledge’. This issue is going to get quite convoluted, the reliability of the senses has a justification in (1) the existence of an external reality (2) evolution. That is, if an external reality exists, natural selection will favor those creatures which can better navigate their environments. The result is that we have senses which are generally reliable in navigating the external world. So when you say that reliability of senses *cannot* be accounted for by an atheist, that’s just plainly false.

Your paragraph is also kind of diluted, you want to talk about the reliability of my senses and then about things that I know. There is only a connection here if we’re speaking about things I might know in virtue of my senses, that is, facts about the external world. As I’ve said, my senses are not involved in my justification of logic. So it’s clear that the reliability of my senses is not a precondition for ALL types of knowledge, only some. It is not clear, however, that I am in err for relying on them.

I suspect that what you mean to argue is something in line with Plantinga, that if I accept both naturalism and evolution then I have some defeater for my position. You need to make this case though, I won’t make it for you.

No; the reliability of your senses must be presupposed. To state that evolution can somehow account for this is a speculation derived from the presupposition that evolution is true. Also, to even perceive an external reality is done with the presupposition that your ability to perceive is in fact reliable. If you cannot account for the reliability of your senses from within your world view, than you don’t know with certainty that you can actually recognize and implement logical laws.It is true that you must assume the reliability of your senses to even contemplate any argument, and your ability to account for that reliability is foundational to the rationality of your world view.

I also never attempted to define knowledge as the definition of knowledge is not the primary issue; the issue is the justification of your senses actually being reliable enough so that you can in fact really KNOW what you know. It’s also not clear that your NOT in err for relying on them. That’s my point; you don’t really KNOW that you can.

You also made a statement about naturalism, so are you a naturalist or not? If so, I would be glad to explain what I feel is a defeater of that position.

Why must the reliability of my senses be presupposed before I consider a priori matters? This is incoherent.I also fail to see any argument for the fact that my evolutionary explanation of the reliability of the senses is ‘speculation’. I don’t want to turn this into a scientific discussion. I also don’t appreciate you just labeling every claim I make as a presupposition. I made a conditional statement:

” … if an external reality exists, natural selection will favor those creatures which can better navigate their environments. The result is that we have senses which are generally reliable in navigating the external world”

Do you disagree that IF an external reality exists and IF evolution by natural selection occurs, it would favor creatures that can better navigate their environments?

You said: “… to even perceive an external reality is done with the presupposition that your ability to perceive is in fact reliable…”

Why is this true? To perceive an external reality is simply to perceive an external reality. I can perceive an external reality without supposing that my perceptions are reliable. I would a belief similar to “…it seems that I am perceiving X”… while “I am perceiving X” can be false, I cannot see how “… it seems that I am perceiving X” can be false.

You NEED to define what you mean by knowledge because you make statements such as: “…the issue is the justification of your senses actually being reliable enough so that you can in fact really KNOW what you know…”

What do you mean by “knowing?” That is a very important issue.

You have not shown that ALL knowledge relies upon sense experience, in fact, that assertion is just blatantly wrong. Why, then, is this discussion about the reliability of my senses relevant to the justification of conventionalism given that such justification is not an a posteriori manner?

” … if an external reality exists, natural selection will favor those creatures which can better navigate their environments. The result is that we have senses which are generally reliable in navigating the external world”-MitchellLike I said, this statement is made with the presupposition that evolution is true. But even if it were true, that doesn’t mean that having reliable senses equates to a survival value that natural selection would preserve. Things like bacteria and plants have no senses or perceptions; and they manage to survive very well without them. If your claim is that these things evolved as well, than you bear the burden of proof that they in fact did, but then of course we’ll have to get into the discussion of irreducible complexity and irreversible complexity for both, and also how photosynthesis evolved. We then would have to get into how your evidences actually relates to the scientific method. But, you already said that you don’t want to turn this into a scientific discussion.

“Do you disagree that IF an external reality exists and IF evolution by natural selection occurs, it would favor creatures that can better navigate their environments?”-Mitchell.

Yes sir, I disagree.

Also, if evolution were true, we wouldn’t have any reason to believe that our perceptions of the external world actually DO reflect reality, this therefore renders your very argument for conventionalism a non sequitur at best.

What I mean by knowing is simply knowledge gained by use of the senses, two of the most implemented in learning being sight and sound. I think it to be foolish to claim that the attainment of knowledge is accomplished without at least some of your senses. If this can be done, the burden of proof is on you to at least explain how this is possible.

My conditional statement is not made with the presupposition that either the ‘if’ or a ‘then’ is true. I think you need to read up on the nature of conditionals.Further, I am not a scientist nor is my job to tackle the “creationist problems” that have been tackled time and time again by various experts in various scientific fields.

You said: “Also, if evolution were true, we wouldn’t have any reason to believe that our perceptions of the external world actually DO reflect reality, this therefore renders your very argument for conventionalism a non sequitur at best.”

Again, you have not given ANY argument for this statement and for the third time I am now repeating that the conventionalist justification is an A PRIORI justification, sense experience is absolutely irrelevant!

Your definition of knowledge also seem inept for it denies knowledge of ALL a priori truths. The burden is not on me to show that there are a priori truths, it’s on you to show that the “a priori”truths are actually a posteriori. That is absolutely incoherent…

So, I feel the need to focus the conversation yet again. Since it is not the case that the justification of conventionalism requires any empirical support whatsoever, and since you have also not provided any argument showing that my cognitive faculties are unreliable, and further since you’ve only attempted to offer an irrelevant argument regarding knowledge acquired through the senses (of which conventionalism is no such knowledge), why should I accept your claim that conventionalism is incoherent?

Dude, just forget it. It is obvious that you either do not understand the argument, or your avoiding it all together. I also think that we’re operating on two different levels here, you’re aiming to defend your argument, and I’m aiming at your ability to make the argument to begin with by pointing out that your world view cannot account for the other preconditions of intelligibility, and I still don’t believe that you accounted for logical laws, it sounds like all guess work to me, you have also failed to address a lot of my core arguments. So I believe its best to call it quits now before I have 200 posts on my profile over a topic that we’ll never agree on. If you wish to discuss other topics, I’m for it; and I will glad to show you Lisle’s review of your articles if I do in fact get a response from him.

(a) I have authored a paper outlining my criticism against presuppositionalism in such a manner that if my criticisms are sound then Christian Theism cannot possibly account for the laws of logic

(b) I have been challenged, after posting the paper, to account for my preconditions lest my arguments be cast aside

(c) I strongly feel that if my arguments are utilized by the Christian presuppositionalist within the Christian presuppositionalist worldview, and if they are sound, they render the worldview internally incoherent

(d) I strongly feel that if the arguments are utilized in such a manner outlined by (c) and they do establish the conclusion that Christian Theism cannot account for the laws of logic, this conclusion may not be simply dismissed by a statement  that amounts to “Well, yes it does…”

(e) I have, in response to being asked, outlined the conventionalist justification of logic such that even without my first paper, if the justification is internally coherent (and possibly true) the TAG is defeated

(f) I do feel that the conventionalist justification of logic is internally coherent and by proxy, I do believe the TAG to be unsound