Before I begin, I would like to make the point that the claims in my paper do not need to be true for the TAG to be defeated (with regard to logic, in this circumstance). The TAG fails due to the fact that logical conventionalism is coherent. Zao briefly touches upon this point, which I will address later, but I want to make it clear that my paper attempts to go beyond the mere claim that “logic does not presuppose God” and suggest something closer to the idea that it cannot.

The Criticisms

In my paper, I remark:

It seems to me that some hybridization of any of the mentioned means of justification may bring about a new means of justification. For example, a hybridization of an a priori and conventionalist system may succeed in providing the justification of logic sought by Bahnsen, but in a manner wherein the new system may be thought of as unique to both previous a priori systems, and forms of conventionalism.

Zao takes issue with this, stating:

Mitch starts off on the wrong foot immediately by proposing a hypothetical “hybridization” of two positions which is also “unique” to those other positions. So, is it a “hybrid” or is it “unique”?

I don’t think that one needs to choose between something being a hybrid, or unique. It’s doesn’t seem to be an either/or situation. For example, take gas-powered automobiles  and electric automobiles and combine the two concepts so that we create a gas-electric hybrid. In this circumstance we have a car that is unique in that there is a property that members of the previous categories do not have, namely, the property of being both gas and electric powered. Must we agree with Zao’s criteria that because this car is a hybrid, it cannot be unique or vice versa? I don’t think so, in fact it seems to me that it may be unique by being a hybrid!

Zao suggests that if there is such a system, I should present it rather than bringing it up as a hypothetical because it isn’t an objection. I think, however, if Zao understood me correctly he(?) would see that I merely rely on the possibility of a system and that this possibility is enough to make the point I wanted to make.

He also takes issue with the formal presentation of the TAG I’ve included in my paper which I’ve borrowed from Sean Choi. Zao states:

…advances have been made in presuppositionalism which have shown Choi’s position to be mistaken. Don Collett has argued effectively (in Revelation and Reason edited by K. Scott Oliphint) that Van Til’s conception of presuppositional semantics is identical to the Strawson/Van Fraasen semantics, which makes a clear distinction between “presupposition” and “implication.” (Even John Frame has accepted Collett’s argumentation in this respect.)

Choi presents his formulation of the TAG as a traditional transcendental argument (a la Kant) which would suggest (in this context) that the existence of logic implies the existence of God. Strawson in attempting to formalize a sufficient theory of presupposition proposes something similar to the following:

P presupposes Q if and only if Q is true provided P is true or P is false.

Where P is logic and Q is God, if one is to use this formulation instead of the previous, we would not say that the existence of logic implies God but that even the denial of the existence of logic also presupposes God. But what real difference does this make to our discussion? If I’m missing something then I wait to be informed, but it seems to me that even under this view the claim that “Both the truth of P or falisity of P presupposes Q” will reduce, in our discussion, to the claim that “logic presupposes the existence of God” since I am not denying the existence of logic. In other words, what difference does this make to any of my subsequent criticisms insofar as they pertain to the presuppositionalist ideas I mention?

This much can be said about the entire section of my paper where I introduce Choi’s formalism. It is of course nice to have something with which to work, but I am not dependent on this formulation. The arguments in my paper can be extended and applied to any (as I can conceive) assertion that amounts to “logic presupposes God.”

I go on to criticize Bahnsen’s idea of the “impossibility of the contrary” stating:

But what might this mean for our discussion? If Bahnsen is permitted to carry on with his criteria, then if any a priori, a posteriori or conventionalist justifications of logic are shown to be false (and subsequently, the worldviews that house and depend on them) all other formulations which properly fall under those headings will also be false (worldviews included) since they employ the same proposition, namely, ‘Christianity is false’. Of course, this is not sound reasoning unless the shared proposition is what is causing the justification to be false. Bahnsen needs to show that ‘Christianity is false’ is the ‘false-making’ proposition of all non-Christian worldviews, and it doesn’t seem that this is possible by any means other than (i) showing that all possible non-Christian justifications will have ‘Christianity is false’ as the onlyproposition in common (for if there is even one other proposition shared by these worldviews, how might one disqualify that proposition as possibly being the ‘false-maker’?), and (ii) showing that Christianity is not false. The obvious problem is that if (ii) is shown, the TAG becomes superfluous as it is no longer needed; one has already arrived at the truth of Christian theism, and for (i) to be shown, one still has to have an awareness of “every single variation of unbelieving philosophy.”

Zao replies that the false-maker of the proposition is its axiomatic nature. But I cannot see any reason to accept the claim that every worldview which has the proposition “Christianity is false” has that proposition as an axiom.

He states:

If the most basic presupposition of a non-Christian worldview is “not Christianity” (which appears to be definitional, given the above framework), then it is the basic nature of the presupposition which exerts a rational controlling influence on all other worldview content. It is not merely one proposition among many, floating loose and free in a certain worldview, but is rather foundational.

Again, why is this true? It seems to me that the only reason for claiming that “Christianity is false” is the most basic presupposition of non-Christian worldviews lies simply in identifying them as non-Christian worldviews. That is to say, I might identify some worldview as being non-Mitchist because I see that their worldview does not utilize what I utilize as my axiomatic foundation but I cannot see how this entails that “Mitchism is false” becomes their foundational axiom. It also seems that depending on who is looking at Bob’s worldview, he has several other axioms! For instance, what if a Muslim is looking at Bob’s worldview, does he now have as a foundational axiom that “Islam is false?” If a Hindu is looking at his worldview, does he now have as foundational the axiom that “Hinduism is false?” It even seems that atheists can analyze Zao’s worldview under his own criteria and suggest that he has as a foundational axiom that “Atheism is false” as his most basic presupposition.

Further, imagine Bob the Buddhist who has as his foundational axiom “Buddhism is true.” If we take Zao’s criteria, then since Bob the Buddhist can be identified as possessing a non-Christian worldview it follows that he has, also as a foundational axiom that “Christianity is false.” We can say that he’d also have as foundational axioms, under Zao’s criteria, propositions such as “Islam is false,” “Confucianism is false,” and “Scientology is false.” It seems more proper to say that Bob merely has the axiom “Buddhism is true” (if even this), and that he deduces from this postulate all of the other aforementioned propositions. That is to say, “Christianity is false” is not an axiom for Bob, it’s a deduction and so like other deductions it is “floating loose and free”. If we are to follow Zao’s criteria, it seems we render the term “axiom” meaningless. In fact Bob would have possibly an infinite number of axioms about religions of which he has not even heard! I see no reason to accept such absurdity.

In further response to my mention of Fristianity, Zao responds:

Being quite thoroughly familiar with various Fristianity objections, I had to chuckle at this one. I apologize for it, but I did. Let’s be perfectly clear here: an atheist can get zero cash value out of the Fristianity objection in debate with a Christian. Are you planning on being baptized in the name of the Father, Son, Holy Spirit and “Fred” anytime soon, Mitch?

The Fristianity objection, if sound, merely shows that the central claim of presuppositionalism is false. That is, if the Fristianity objection holds then it is false that no non-Christian theistic methods can possibly justify X, Y, Z. This is all I was intending to show.

Moving right along we come to my application of a Euthyphro-like dilemma to the laws of logic. Similar to many Christians with regard to the actual Euthyphro dilemma, Zao takes the route of stating:

The Christian’s argument is that logical laws are a reflection of God’s thought which is in accordance with God’s nature, which are all necessary.

But analyze what I said in the section, as Zao even quoted himself:

Frame essentially makes the claim that it is logically impossible for the nature of God to change. But the standard Frame is using to identify logical possibility is allegedly the nature of God. As such, his claim appears to be represented more accurately as:

(C)  Based on God’s nature it is logically impossible for God’s nature to be different because God is necessarily a rational God

This does not seem to assist in any regard as what is rational is allegedly determined by God’s nature. So to argue that God’s nature must be the way it is because God is necessarily rational seems to only appeal to a standard of rationality that is separate from God, otherwise it is clearly circular.

In what manner would it be the case that God’s nature was not rational? It does not seem that a God who forms the basis of logical principles and thereby is the standard of rationality can ever be irrational (though he may certainly appear irrational when judged by a foreign standard). That is to say, if one wants to state that the Christian God forms the basis of rationality and the logical principles thereby in effect cannot be anything other than what they are, they must be appealing to a standard of logic that is separate from God’s nature as to appeal solely to God’s nature does not sufficiently answer the question; it is a non-answer.

If Zao does not think that (C) is circular, I suggest he read a bit closer. He says that my dilemma is circular in itself because the first horn “…asserts that there is a meaningful sense in which logic is independent of the thought of God.” What is the implication of the aforementioned circularity in basing them on God? It seems to me that, as a direct implication, we must conclude that the necessary principles of logic indeed are external to God just as is the case with necessary moral principles and the original Euthyphro dilemma. I have not, as Zao has suggested, assumed that they are independent to show they are independent, I’ve formulated a dilemma and shown that given the alternatives are incoherent we have no choice but to accept that logical principles exist independently of God.

We might even supplement this by raising a point that was conveyed to me by a fellow UP.net member. Zao stated that the logical laws are a reflection of God’s thought and that God thinks logically. Moving over the seemingly obvious incoherence in such a statement, one might want to ask what it even means to say that God thinks logically? Logic permits us to deduce from premises, distinguish conclusions and so on. But God, if he is omniscient, surely does not have to do any of these things to have knowledge. God does not “reason” to his conclusions, he simply knows them. To say that the logical laws are reflections of God’s logical thinking stands in opposition to the idea that God knows all there is to know. Truly omniscient beings do not require logic, because they do not require a means to apprehend knowledge. This, I think, just adds to the incoherence of stating that logical principles reflect God’s rational thought.

In my section entitled “God and the Abstract” I offered an argument which is basically as follows:

The dependence relationship between “God exists” and “logical principles exist” seems problematic. If God is the source of all things other than himself, and he depends on nothing for his existence, surely the relationship must be asymmetrical (with primacy granted to God), but it appears not to be. It can be shown, in fact, that God depends on logical principles for his existence.

Lewis’ counterfactual semantics tell us that ‘any proposition is counterfactually implied by a necessarily false proposition’. Since “logical principles do not exist” is a necessarily false proposition, it counterfactually implies any proposition whatsoever.[21] So it is also true that if logical principles did not exist, neither would God. Thus, God depends on logical principles for his existence.

The relationship between the existence of logical principles and the existence of God would be asymmetrical iff God depended on nothing for his being and logical principles depended wholly on him. In this regard, the relationship of dependence is one-way; logical principles depend on God but not vice versa. If dependence is asymmetrical, then logic cannot depend on God as it has been shown that God depends on logic.

The asymmetrical relationship can be depicted further: where P refers to logical principles and Q refers to God. If P depends on Q asymmetrically, then the worlds in which P is true must be a proper subset of the worlds in which Q is true. Since it is the case that the principles of logic hold in every world, and the set of all worlds is not a proper subset of any other set of worlds, the laws of logic cannot depend on anything, including God.

Zao responds:

Given the nature of the points under contention (the existence of God and the relationship between God and logic), to argue that “logical principles do not exist” counterfactually implies that God depends on logical principles for his existence is to beg the question in a rather bald and obvious sort of way. How about, “God does not exist” is a necessarily false statement? Given that TAG is intended to argue for the necessary existence of God, to assume the contingency of God’s existence upon logic in order to prove God is contingent upon logic is, well, unpersuasive (to put it mildly).

I might be mistaken, but it seems to me that Zao interprets my argument as an argument against the existence of God. This is not the case, however. I can accept both the necessary existence of God and the necessary existence of logical principles, and still deny the type of relationship that the presuppositionalist is proposing. It’s not the necessary existence of either of these things that is the issue, it’s the proposed asymmetrical relationship between God and logic. I think Zao has really misunderstood the thrust of my argument here.

After a point about my brief treatment of divine simplicity and Trinitarianism (I agree, that could be a paper unto itself!) Zao closes with a very brief criticism of logical conventionalism. Zao states:

Finally, we have a section where logic is said to be both conventional while necessary and universal. This is rather fun. It’s like something from Alice in Wonderland. “Sentence first – verdict afterwards!

This is a claim that is thrown around a lot, and it is a claim that is just simply false. There simply is no problem with logic being conventional, while having its principles be necessarily true. Zao is welcome to either read the literature cited in my paper, the brief treatment here or wait for an upcoming article I’m expecting authored by a logician.

Conclusion

Again, the arguments in my paper are not needed to show that the TAG fails, the mere coherence of Conventionalism serves as a defeater for the endeavor. What my arguments seek to show is that logic cannot be based on God in any such implied way. I can only say that Zao’s brief treatment of Conventionalism towards the end of his post seems to violate his own suggestion of “… [understanding] the matter for [one's self] before attempting to criticize…”

P.S: I’d like to politely ask that in the future Zao link to my articles rather than pasting them in full. I’d also like to ask that he adds a hyperlink to the specific post he’s writing about. Thanks!

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

“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. ” (spelling corrections mine)

What I have tried to explain is that Joshua should simply take my arguments and run them as an internal critique in his own worldview, a sort of internal reductio. The soundness of my article, if truly sound, will not be limited to one worldview. That is to say, if my argument truly does establish its conclusion it will do so if parsed through his own worldview and if that conclusion is such that it shows that his worldview cannot account for logic, then all the worse for his worldview! He may not simply beg the question in favor of his position after seeing the outcome of my criticisms. To this suggestion he has responded:

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.

This is a pretty heavy charge, but I look forward to his analysis. I do recommend, of course, that it take into account the following material.

With that said, in an effort to quell any further attempts at avoiding the ‘meat’ of my paper due to an “inability to account for the laws of logic,” I will present the conventionalist justification of logic. In my discussions with presuppositionalists they have seemed to largely misunderstand the system and in turn create strawmen of their own to argue against. We must be cognizant now that the TAG as I’ve outlined in the previously linked paper or the statement that only the Christian worldview can account for the laws of logic requires that no other justification be possibly true. If the presentation of conventionalism is coherent it saddens me to say that one will not even need to read my paper to show that TAG (and presuppositionalism) fails. Further, there are those who would assert that presuppositionalism is the true apologetic system in that it is the one that Christianity explicitly endorses. There are also those who say that presuppositionalism/TAG cannot possibly be false because of the guarantee given by scripture. For these people, there is much more at stake than merely the coherence of the TAG, they also risk the truthhood of Christianity.

If the TAG, and further, presuppositionalism, are the true exemplifications of Christianity it follows that their defeat is symbiotically a defeat of Christianity. We can demonstrate this with a simple modus tollens:

(1) If Christianity is true, then the TAG succeeds

(2) The TAG does not succeed

(3) Therefore, Christianity is not true

What of course needs to be shown is (2), and while I feel that I’ve shown it sufficiently in the aforementioned paper, as I’ve said there are those who wish to address my supposed “inabilities.” Let us analyze if the claim that conventionalism cannot possibly account for the laws of logic is true.

What is Conventionalism?

What follows will be a series of excerpts I’ve chosen from Creath’s article that I feel outline the conventionalist justification of logic quite well.

Carnap made a refreshing and welcome suggestion: the axioms can be construed as definitions (implicit definitions) and their assertion as commitment to a language containing the terms so defined. The axioms or postulates need no further epistemic justification because a language is neither true nor false, and one is free to choose a language in any convenient way. If someone else should choose other apparently conflicting postulates, there is in fact no disagreement because each postulate set is constitutive of the concepts it employs, and hence the one body of postulates is not denying what the other is asserting. In this manner the postulates are not even intended to reflect an antecedently and independently existing reality, but rather literally to create the claims they express.

It may be that some postulate sets are better than others. But the ‘betterness’ in question concerns their practical usefulness: some are more powerful or easier to use than others. In terms of epistemic justification or cognitive warrant they are all on a par. Indeed, they are the ‘meter sticks’ for the justification of anything else. Epistemically the choice among them is conventional, though the constraints imposed by pragmatic utility can be significant. For example, an inconsistent postulate set is not very useful. For most logicians of the period, including Carnap, every sentence as well as its negation would trivially follow from a contradiction. An inconsistent postulate set would therefore fail to draw any cognitively interesting distinctions among sentences or beliefs. Though the preference for consistent systems is treated as a pragmatic one, the pragmatic considerations are powerful indeed.

In this first excerpt we see some constant presuppositionalist claims addressed. If logic is conventional, can’t people just choose different conventions? If some people choose different conventions than others, they will be contradicting each other, so how do we know which one is true? The answers to these questions are laid quite simply in the excerpt. Each language or system of logic will have a set of definitions that require no further epistemic justification. Think about the English language, there are definitions of words but to ask why a certain word is defined as such rather than some other definition is a question that simply makes no sense for languages which are neither true nor false, they simply are. Further, if someone chooses some language different than ours (say, French), there is no contradiction because the French language cannot disagree with the English language because they are creating their claims independently of one another.

Pragmatism comes into play when want to decide which system to use. Now, keep in mind that Carnap is not proposing that people somehow “choose” their basic brain languages (the language upon which they would choose all other languages). This is as silly as suggesting that one should be able to choose their genetic makeup as to yield a certain eye-color. Our fundamental operating language, our basic logical brain language (logical because there is no such thing as non-logical languages) is not chosen by us, but rather is the precondition for all other choosing. For the systems we can choose, be it in mathematics or computer science, we use the ones that allow us to perform certain tasks. We would not choose a trivial system because anything follows from trivial systems, the answer to every proposition is “Yes,” clearly this is useless.

“This discussion of pragmatic usefulness and explication must not obscure, however, the epistemic core of Carnap’s doctrine. The choice among alternative postulate sets is epistemically arbitrary; the choice is a matter of convention. Moreover, the postulates themselves are the fundamental epistemic doctrine.”

Again, where choice is possible amongst systems the choice is arbitrary. Creath continues:

At this point it would be well to say a bit more about convention, for it is not always clear what is at stake in saying that something is a matter of convention (Quine, 1936). Plainly, when Carnap speaks of the semantic and epistemic features of our language as conventional, he does not mean to suggest that they are the products of some actual legislative assembly convened in antiquity. But shorn of such unhelpful metaphor, what does conventionality come to? The answer, in essence, is that to lay down a linguistic convention is to adopt a certain scheme of justification. This scheme involves two specific features: first, there are alternatives to certain aspects of the justificatory system; and, second, the choice among these alternatives is arbitrary in the sense that no justification is required for the choice. In particular, to say that postulates are laid down by convention commits one to the idea that there are alternative postulates that could have been chosen, but were not. It commits one likewise to the idea that no further epistemic justification for the choice of postulates is required. Conventions are not designed to reflect antecedent and independent facts; if they were thus designed one would have to show that they had done so. Rather, the postulates (together with the other conventions) create the truths that they, -the postulates, express.

So put, conventionalism is the adoption of a system of justification. Other systems could have been chosen, but weren’t and no justification is required for the choice. Further, conventionalist systems are not reflecting some external reality, they really are creating their truths. We will see a further explanation of this below.

Creath continues:

That the conventions constituting the system of justification are at bottom arbitrary poses no threat whatever to the objectivity of the postulates and their consequences. This was of particular concern to Carnap because he thought that all of logic and mathematics, insofar as the claims thereof can be assessed at all, is to be justified as are postulates and their consequences. Once a system of justification is chosen, i.e., once the various terms of the language are given a definite sense, it is a completely objective matter whether B is a consequence of A. It in no way depends on what any person may happen to imagine, think, believe, or know about these sentences. It is likewise a completely objective matter whether or not a given claim needs further justification. These things are no more subjective than the truth value of the claim “All swans are white”, given of course that the meanings of the terms are fixed. If the word ‘white’ has a sense different than it in fact does, then the truth value of the claim might be different, but this in no way impugns the objectivity of “All swans are white”.

Here we have an answer to the common presuppositionalist assertion that “if logical principles are conventional, they are not necessary.” As the quotation says, once we adopt a system of justification whether or not X is true, or Y is true is a completely objective matter. To quote myself in a previous discussion with presuppositionalist Chris Bolt:

There is a distinction between “object-level” and “meta-level”. Consider a meta-ethical circumstance, where an evolutionary account of morality may be charged with becoming eliminitivist. “if I do some good deed X just because I am programmed to, then X is not really good to do, it’s just part of my programming” But these statements are operating on different levels. Both the following propositions would be true: “X really is good to do” and “X really is just a part of my biological programing, and that’s the only reason I think X is good to do” A contradiction only occurs when both statements are taken to be expressing a proposition of the same level.

Applied to logic, “X is really necessarily true, everywhere, regardless of what anyone thinks, and regardless of anyone’s conventions. And X really is just part of a system of conventions I have adopted as part of my programming.”

Thus we can see that the common charges against conventionalism by the presuppositionalists are simply misunderstandings. Conventionalism does not entail that some logical systems will contradict others, nor does it entail that everything becomes subjective and that logical principles are no longer necessary. Now, so long as conventionalism is a possible justification of the laws of logic, the TAG (and for some people, Christianity) is simply defeated:

(1) If Christianity is true, the TAG succeeds

(2) If some system other than Christian Theism can possibly account for the laws of logic then that TAG does not succeed

(3) Conventionalism possibly accounts for the laws of logic

(4) The TAG does not succeed

(5) Therefore, Christianity is not true

Conclusion

In dispelling the myths surrounding conventionalism put forth by presuppositionalists it should be clear and evident that conventionalism is coherent. Further, given its coherence it is a possible justification of the laws of logic, showing that the TAG fails. Coupled with the criticisms in my aforementioned paper we are left with the possibility of a conventionalist justification and the impossibility of Christian Theistic justification. For certain Christians, these conclusions are nothing less than devastating. If their position is the one I’ve outlined in the syllogisms, not only can Christian Theism not account for the laws of logic, it is false altogether.