Friday, March 4, 2011

Rationality, Validity, and Soundness

One of the constant refrains of the New Atheist movement is that theists, Christians in particular, are irrational to accept the teachings and doctrines that they do. In doing so, I suspect they often make the mistake of conflating rationality with soundness. That is, they seem to believe if something is ultimately not true someone is irrational to accept it as such. While it is true that it is surely irrational to accept as true that which he knows as false, this article seeks to show the difference between the concepts. The Christian may be ultimately rational even if his beliefs turn out to be false.

First, we should state what rationality is. Rationality is holding beliefs for a reason or set of reasons, when the reasons stated would indeed result in the stated conclusion (or when we should expect this to be the case). A good example is belief in the exterior world around us as being real. One cannot demonstrate with absolute certainty it is in fact real; yet he is wholly rational in taking it to be the case that it is real. It is in this way we use rationality almost as a synonym for “reasonable.” Notice the rationality of holding the belief that the exterior world is real is not diminished even in the event that it is ontologically true such a world is not real.

Next, we need to understand validity. This refers to the form of the argument itself. A valid logical form for an argument guarantees that if the premises are true then the argument’s conclusion is true. We explore this at this juncture because it is a corollary of rationality; if one is rational, then his argument is valid. However, it does not follow that if one has valid reasoning he is being rational. A brief example: If Abraham Lincoln was shot and killed in the 19th century, then my father’s name is Glenn. Abraham Lincoln was shot and killed in the 19th century. Therefore, my father’s name is Glenn. This argument, though valid and sound, is not rational. That is to say, I have no reason to believe the material conditional without already knowing both clauses as true, in which case I am only rational in accepting the conclusion on other grounds, not on this argument.

Next, we must understand soundness. An argument is sound if the form is valid and if the premises are in fact true. However, the example in the preceding paragraph is enough to show that simply because an argument is valid and sound a person may not be rational in believing the argument’s conclusion to be true on those particular grounds. In fact, the evaluator of a given argument may not even be aware of the soundness of the argument (epistemically) so that even if the argument fulfills both criteria he will not accept the conclusion (since he is not rational in accepting it). There must be some sort of reason for taking the argument or the premises of an argument (which may themselves be conclusions of other arguments) as true.

Finally, we must examine the application to the Christian. Does the Christian have a reason to accept certain beliefs or arguments as true? Yes he does! Many Christians take the classic arguments for theism and Christianity (such as the cosmological, ontological, teleological, moral, and the Resurrection hypothesis) as rational warrant for the claim that Christianity is true.1 When New Atheists then claim Christians are being irrational on the basis that the arguments’ conclusions are in fact false, they are confusing the justification for a claim with the claim’s being true. The first premise of the kalam is called the “causal principle.” This causal principle may in fact turn out to be false (though it’s hard to see how), yet even the most hardened atheist must confess it at least appears to be true, and thus one is rational in accepting it (even if it turned out to be false). Christians who proffer bad or faulty arguments in which formally invalid reasoning is done, or who have no reason to believe one or more of the premises, are indeed being irrational on those grounds. But simply because one disagrees with a premise, or believes it to be false, it doesn’t follow that the Christian is irrational. In fact, such a view may itself be irrational!

1 There are many Christians who do not use any of these arguments to justify their belief, but the internal witness of the Holy Spirit acts as justification for these believers (Romans 8:16), so that they are not condemned to irrationality.

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  1. Randy, I want to propose another possible reason for this, though, not a justifiable one. Perhaps many atheists have simply met unintelligent Christians.

    For example, on my website's Facebook page (it's an atheist site) there are a few Christians who comment regularly on my posts. Their comments are really bad. I'm tempted to tell them they are doing more harm than good, but I try to be polite and respond to them. They commit obvious fallacies on a regular basis, have a poor grasp of physics, etc. I'm sure you've seen the type on both sides.

    Now, someone could take that and conflate it to the whole of Christianity. This would, of course, be completely wrong, but I just wanted to offer another possible alternative. It doesn't make the New Atheist irrationality argument look any better (if indeed they are using it regularly), but may provide some more understanding of how the error originated.

  2. Thanks for commenting Mike! I agree too many poor arguments on both sides (and especially Christian) have brought this about. I can't count the number of times any Christian or theistic argument has been dismissed on the grounds that Christianity is itself irrational. I understand why extrapolating or generalizing would be somewhat appropriate, but it would not be appropriate to reject substantive dialogue (or even the claims themselves) because of this! You don't strike me as that type. You may not even be of the New Atheist type! Of course, I wouldn't have any way of knowing. Hopefully we'll see ya around!

  3. Doesn't the doctrine of faith operate independently of rationality, validity and soundness?

  4. GAS3, thanks for commenting! It seems to me impossible for faith to operate outside of soundness--either something is true or it is not, ontologically speaking. But perhaps you are asking if faith can be had in place of these three, or without these three, epistemically. To that I would say yes, with one caveat: the believer may use the internal witness of the Holy Spirit as confirmatory of his own faith and still be rational (after all, if it is true, then the Spirit does operate as such, and thus it is rational to believe on that basis for the one who receives such a confirmatory witness). In respect to that we must distinguish between the Christian's knowing it to be true, and showing it. This would fall under the former category, not the latter.

    However, faith does not exclude rationality a priori. For instance, suppose my wife comes to me and says, "pack your bags, because tomorrow I am going to book us a nice resort hotel!" Now, as it turns out, she has never booked a hotel herself on short notice. But she also never lies to me. I am rational in accepting her word as true, even though I am not certain of it, and even though she's never done what she says she is about to do! I am taking it on faith, but it is a faith well-placed. :)

  5. I probably would agree that I'm not a "new atheist." That term seems so vague, though, that I'm not entirely sure what it means. I'd like to say I'm more like Mackie, but that would be too flattering of me.

  6. Hey Mike. :) I totally agree "new atheist" is a vague term. However, it is generally agreed not to mean "contemporary" atheism, but rather an attitude of engagement coupled with popular-level work (as opposed to scholarly-level). Like Dawkins for instance. While he is a top-rate biologist, as Craig would say, when it comes to philosophy he is "strictly a layman." I also understand your reference to Mackie. He was brilliant. A contemporary atheist that I enjoyed listening to (both for tone and content) is Austin Dacey. He doesn't exaggerate his claims, but he puts forth his arguments forcefully and with civility. You gotta respect that. :) I am in the process of sending back an A for the Q that came earlier. BTW, how did you hear of this blog?

  7. Hi Randy. I saw your answer. Thank you for that, and I'll look into those resources. To answer your question, I've enjoyed your comments on Reasonable Faith and I clicked on the link in your tagline. I like what I've seen on the blog so far.

    I'd also like to ask about your footnote to this post. I wonder if I'm missing something because you say someone can be justified in belief through the internal witness of the Holy Spirit. It seems as though one of the things they would be justified to believe is the existence of the Holy Spirit (as expressed in the Bible). Wouldn't this be circular? Perhaps you can clarify.

  8. Hi Mike. Ah yes--I haven't been on those forums lately, but I love 'em!

    As I mentioned briefly in response to GAS3 on this comment thread, we must recognize the difference between showing something as true and knowing it as true. It would surely be circular to try to show you that what I believe is true by the internal witness of the Spirit (since you would have to take my word the Spirit is real, and in order to do that you'd have to know it was real, and so on).

    As Craig says, "the self-authenticating witness of God's Holy the immediate experiencing of God himself." (Reasonable Faith, 43) This experience entails the knowledge of certain central Christian doctrines for the believer himself (though not for other people). If the Spirit performs this function, then the believer will know it to be authentic. But we wouldn't use this as an argument for why it is true, for then we would use the very thing we seek to prove. So it all depends on the nature of what we are doing. It's much the same for knowing something as true via any centalized experience. I know the outside world is real, in large part because I experience it. But this would be a circular way of proving the outside world to be true. However, I am rational in accepting it as such. Alvin Plantinga shows there is at least basic justification for belief in other minds and warranted Christian belief in works by those (similar) titles. I hope that at least helps!

  9. Randy, thanks for making the point -- which I have made repeatedly to atheists -- that Christian belief, at least as held by most, is in no sense "irrational." Unfortunately, most people in the discussion (including Christians) too often think in black/white and either/or, when the potential solutions lie along a very wide spectrum of possibilities. Folks seem uncomfortable with fuzz or gray.

  10. Thanks for commenting mad! I appreciate it and the thoughts. Thanks for reading!


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