Do what thou wilt shall be the whole of the Law.

Thursday, December 18, 2014

Believers Say the Darndest Things: "You Can’t Prove Reason with Reason. Therefore, _____."

It appears to be impossible to use reason to prove that reason is absolutely reliable. The operation of evidence-based inquiry relies on presuppositions that were not, themselves, arrived at by evidence-based inquiry.

There are some religious believers who learn these ideas and run completely off the rails with them, mistakenly thinking that they’ve gotten hold of some knockout blow to evidence-based inquiry.

The purpose of this post is to explore the arguments that believers often make based on these ideas, with the intent to show exactly where believers go wrong.

After all, in conversations between believers and skeptics, it is very common for the skeptics to request evidence for the wacky claims that believers make (since, obviously, nobody has any reason to think that a claim is likely true unless there is evidence for it…and since the believer actually does accept the claim under discussion, the believer must implicitly think there is evidence for it).

Sometimes this request is met with honest effort on the part of believers. They’ll point to things that they mistakenly think are evidence. Other times, believers will try to redefine what is meant by “evidence,” either honestly misunderstanding or purposefully and dishonestly confusing the issue. They’ll claim that their subjective feelings are somehow “evidence” for the existence of powers or beings that, if these powers or beings were real, would have a detectable effect on the world outside of these believers’ heads.

But on some occasions, the believers will question the very idea that evidence and reason are useful tools in the first place.

“What evidence,” they sometimes ask, thinking themselves clever, “do you have that all claims require evidence?”

Another way to phrase this objection is, “What’s your rational argument for thinking that reason is an effective tool? Oho! You can’t do it without being circular!” The implication is that any rational proof of reason’s effectiveness has to begin from the presumption that reason is effective, thereby begging the question (since it assumes the thing that it’s trying to prove).

In other words, their argument boils down to “You can’t prove reason with reason. Therefore, God.” [Or whatever nutty claim they’re making]

What’s happening here is that the believers in question have learned a small bit of philosophy. But, as I’ve noted elsewhere, a little philosophy can be a dangerous thing. Their half-comprehension of this issue leads them to all kinds of confusion.

Read on for a full explanation.

The most obvious problem with this believer script is that it contradicts itself: the argument continues to use reason after ineptly trying to discredit reason. If nobody has reason to think that reason is reliable, then…then we can’t complete this sentence. *No* argument is possible, including the arguments that they want to make. Even the conclusion “*No* argument is possible” cannot be formed.

Using reason to argue against reason is a self-defeating argument. So is pretending to have determined that reason is unreliable and then reasoning one’s way to new conclusions about gods, spirits, or magic powers.

And it’s no use to say, “Exactly! One has to experience these things, not reason about them!” because the conclusion “What I just experienced was a spirit,” or whatever, is necessarily reached through the application of reason. Bare experience, by itself, can only tell you that there was an experience of some kind. It cannot tell you about the nature of that experience. [See here for more]

But there are more advanced versions of this script that rely on misunderstanding the idea of “presuppositions” or “axioms” in philosophy, hoping that semantic confusion will allow the believers to make a false equivalency.

Generally speaking, most philosophers acknowledge that people have to “presuppose” a number of axioms. That is to say, there are a number of things that we take for granted as the basis of thinking without proving to ourselves that they are true. For example, one might argue that we all begin by presupposing that there is a reality to which our senses connect us (that is to say, that we are not brains in vats or in the Matrix). One might also argue that we presuppose the laws of logic (also known as the "logical absolutes"), which are the foundation of the mental process that we call logic (these absolutes are the law of identity, the law of non-contradiction, and the law of the excluded middle). [See here]

The thing that this believer script tries ineptly to object to is the latter point: when skeptics insist on using logic to evaluate claims, believers who use this script object because those same skeptics haven’t used logic to confirm the very foundations of logic (those absolutes mentioned above). Therefore, runs the script, skeptics have no reason to think that logic “works.” They just presuppose it! Therefore, logic is a kind of “faith” since it starts from ideas that just have to be believed without evidence! Therefore, these so-called “skeptics” are admitting that it’s okay to believe things without using evidence. So believers can just presuppose that magic is real. Checkmate, atheists!

Personally, I have a problem with using the word “presuppose” in this context: it suggests a deliberate choice, but the things we’re calling “presuppositions” seem to be the necessary ways that brute facts shape our thinking. I don’t think, for example, that any child encountering the world around him or her for the first time decides to believe that “reality is real” or “reality is not the Matrix.” Rather, “reality” is a label that we retroactively put on our experience, and the question of whether reality is “ultimately real” does not have to enter the equation at all.

That is to say, I’m suggesting that a child encountering the world for the first time does not presuppose that it is “really real,” in the sense that these religious believers might mean the words “presuppose” and “real.” The child reacts to what he or she encounters, and discovers that the senses are revealing certain things that appear quite consistent. The child later uses the word “reality” as a label for the experience of those consistent things. I’m not convinced that, at any stage of the process, one “presupposes” that reality is “real,” in the sense that they seem to mean.

I feel similarly about the logical absolutes. We might boil these truths down to the fundamental facts that shape our thinking: that a given thing is what it is, is not what it is not, and cannot both be and not be at the same time and in the same way. I don’t think that anyone decides to accept these absolutes as a precursor to thinking: I think, again, an individual encounters a consistent world – in which objects are what they are and are not what they are not – and the consistency of the world becomes the basis for the development of thinking.

All of the above three paragraphs is to say that I remain unconvinced that these “presuppositions” actually are presupposed: I think these “presuppositions” are really just brute facts that influence the development of our thinking. When our thinking develops to the point that we can formally articulate these “presuppositions,” we induce them as likely to be true from our experience. If the objection is simply that induction is probabilistic and not absolute, I would counter that all knowledge appears to be tentative and probabilistic and that absolute knowledge does not appear to be possible. [See here]

But setting aside my quibble with the word “presuppose,” I’m happy to use it for the sake of argument and say that, in this narrowly defined context, I presuppose reality and the logical absolutes. The believer script that I’m discussing in this post, however, tries to equate this “presupposition” with religious faith, but this is a false equivalency.

As you can see from my description above, these “presuppositions” are really the brute facts that seem to shape our thinking. They are adopted out of necessity, not out of choice, which is one of the key reasons that I think the word “presupposition” is misleading.

But religious faith – faith in gods, spirits, or magic – is not a necessary brute fact in the way that the things we were discussing above are. As ever, religious arguments rely on equivocations, obscuring differences with word games, and bait-and-switch.

To the extent that reality and the logical absolutes can be considered “presuppositions,” pretty much everybody, including religious believers, makes those same presuppositions. The religious believers, however, then try to smuggle in God (or spirits or magic) as a presupposition. They’ll say, “Hey, you’re presupposing logic, so I’ll presuppose God! Looks like we both have faith, ehh?”

But we don’t. It’s false equivalence.

Just because pretty much every last thinking person necessarily accepts several points, and just because those universally-agreed-upon points cannot be absolutely proven, and just because we can use the word “presuppositions” to describe these necessary and universally-agreed-upon-points, doesn’t mean that therefore you’re free to “presuppose” any random things you want.

There’s an entire brand of Christian apologetics called “presuppositionalism” that tries to use the semantic difficulties of discussing this topic, and the confusion resulting from the general complexity that arises from talking about it, to bamboozle people into thinking that there must be a God.

I don’t think I’ve ever seen an occult religious believer present a formal presuppositional argument, other than the retarded argument I dealt with above, “everyone’s got presuppositions, so you got faith too, so I can randomly presuppose anything I want, hurr, hurr.” A formal argument from presuppositional apologetics goes something like this, and I imagine that an occultist could easily adapt this argument to make a case for spirits or magic:

We all have presuppositions.

You presuppose the existence of logical absolutes, but you can’t account for them.

I *can* account for them by presupposing the existence of a God whose mind contains those absolutes.

Therefore, God must exist in order for there to be logic.


Such an argument is, of course, ridiculous, but it can be difficult for some people to see exactly what’s wrong with it because most people have not spent a lot of time thinking about the abstract and difficult concepts that it invokes. As I said above, the purpose of these arguments is to bamboozle people. If you can’t persuade them with logic, baffle them with bullshit, and this kind of argument exists to baffle people, to catch them off guard and leave them floundering because they don’t immediately know how to attack it.

The main problem with the above argument is that it conceals three huge assumptions: (1) that logical absolutes *need* to be “accounted” for, (2) that postulating a God actually does “account” for them, and (3) that “God” – whatever that is – doesn’t need to be accounted for, too.

In the first place, who says that logical absolutes need to be accounted for? What if they are simply bare facts?

[As an aside, there’s a huge and interesting debate to be had about what the logical absolutes “are” and whether the word “are” is even the right word. I heard it phrased once that the logical absolutes are not things that have a nature, but they rather are our expression of the nature of things. They appear not to be contingent on anything, including minds. If we removed all minds from the universe, the absolutes would still apply: a tree would still be a tree and not not-a-tree. There just wouldn’t be anyone around to confirm it. Therefore, it seems reasonable to conclude that the logical absolutes are not contingent on *any* mind, even that of a God. If nothing existed at all, they would still apply because nothing would still be nothing and not not-nothing. I’m not sure it even makes sense to speak of “accounting” for them because I don’t see how they’re contingent on anything: it might be best to think of them as bare facts and leave it at that]

In the second place, claiming that there is some being that somehow accounts for the logical absolutes does not actually account for them.

As a demonstration, let’s consider an occultist using this same argument: “I presuppose the existence of magic, and it accounts for the logical absolutes” or “I presuppose the existence of spirits, and they account for the logical absolutes.” Or how about, “I presuppose the existence of a transcendent hippo, and he accounts for the logical absolutes.”

There’s a difference between *saying* that you are accounting for the logical absolutes and *actually* accounting for them. Anyone can invent a story that purports to explain something, but merely inventing a story doesn’t mean that the story is true, nor does it give us any ability to differentiate between competing stories, whether they are stories about God, magic, spirits, pixies, or transcendent hippos.

And finally, the argument assumes that God doesn’t need to be accounted for. If the believer is arguing that the logical absolutes must be “accounted for” – and I see no reason to think that they must – then how does the believer “account for” God (or magic or spirits or consciousness or transcendent hippos or whatever the believer is plugging into the argument)? And if the believer’s argument is “God is defined as a being whom we do not need to account for,” then we can similarly just declare that the logical absolutes don’t need to be accounted for. What’s good for the goose is good for the gander.

Examining the follies of Christian presuppositionalism elucidates how it is a more elaborate version of the “You can’t prove reason with reason. Therefore, God” believer script.

One reason I’m thinking about this topic today is that I recently listened to a fun two-hour debate between Atheist Experience host Matt Dillahunty and Christian Apologist Matt Slick. Although Slick is technically not a presuppositionalist (at least in some ways), he is the originator of a version of a presuppositionalist argument called the Transcendental Argument for the Existence of God (TAG).

The basics of Slick's version of TAG run something like this (paraphrasing it):

People use logic

Logic is of the mind, but people didn’t invent logic. It depends on the logical absolutes.

Those absolutes are conceptual by nature (they’re not physical).

Since they’re conceptual but not dependent on human minds, they must exist in some mind. That mind is the mind of God, QED.


I’m not going to bother going through this argument point-by-point since it should already be clear where I would object to it.

But I will post the debates that Dillahunty and Slick have had about it. Here was their first debate on the subject back in 2009 on The Atheist Experience: [Note: the video is broken up into 6 parts]

[I still remember watching that debate live and being deeply impressed by how well Matt D. handled Slick]

Round two took place less than two weeks ago here:


One of the main points of their disagreement – a point that ends the first debate and takes up a good twenty minutes at the beginning of the second – was over Slick’s contention that the logical absolutes had to be either physical or conceptual. As Matt D. points out, this is not a true dichotomy. A true dichotomy would be physical vs. not-physical. Presenting as a true dichotomy something that is demonstrably not a true dichotomy is fallacious.

It’s downright embarrassing how Slick does not grasp that he’s failed to demonstrate a true dichotomy. In fact, throughout that second discussion especially, it’s abundantly clear that Slick is missing the point of much of what Matt D. says, whether deliberately or accidentally. One thing that emerges quite clearly is the extent to which Slick is hung up on labels: he wants to know whether Matt D. is a “naturalist” or a “materialist” or a “rationalist” or an “idealist,” and in response Matt D. explains his positions, which are often complicated enough that one simple label is not sufficient to encompass them. But Slick seems more interested in locating a particular label so that he can attack the position represented by the label with one of his scripts.

This seems to be a problem, in general, with believers and especially those believers who use this particular script that I’ve been discussing: they’re so caught up in labels – and their ideas about what someone labeled a “materialist” “must believe” or “must presuppose” –that they refuse to engage with the substance of the issues.

Well, that’s two posts in one day…Merry Christmas!


  1. Brilliant stuff particularly the bit about the false equivalence of logical absolutes with metaphysical believer-script claptrap. As Crowley commented (on Liber Al),"We must not suppose for an instant that the Book of the Law is opposed to reason. On the contrary, its own claim to authority rests upon reason, and nothing else."