Tag Archives: evolutionary naturalism

Adventures in Branch-Cutting

Here’s a remarkable paragraph from Graham Oppy’s Atheism and Agnosticism, which appears in a discussion of whether theism or naturalism better explains our mental faculties:

Some – e.g. Plantinga (2012) and Reppert (2009) – argue that our reasoning capacities could not be a socially moulded mix of evolutionary adaptations and exaptations. But those arguments assume the reliability of our reasoning capacities in domains in which it is obvious that our reasoning capacities are highly unreliable: philosophy, religion, politics, and the like. When we make a more accurate assessment of the reliability of our reasoning capacities, we see that that assessment supports the claim that our reasoning capacities are a socially moulded mix of evolutionary adaptations and exaptations. (p. 42)

I had to read these sentences several times to confirm that Oppy really was saying what he seemed to be saying. Note two claims being made here:

  1. Plantinga and Reppert’s arguments assume that our reasoning capacities are reliable in the domain of philosophy (among other domains).
  2. That assumption is false.

In fact, Plantinga’s Evolutionary Argument Against Naturalism (EAAN) does not make that assumption, except in the trivial sense that EAAN is a philosophical argument and thus we have to assume that our capacity for philosophical reasoning is generally reliable if we’re to understand and evaluate the argument (in the same way that we have to assume the general reliability of our sense faculties when reading Plantinga’s books and articles). Plantinga’s argument is this: if naturalism is true, there’s no reason to think that our reasoning capacities are reliably truth-directed in any domain. (Actually, that’s a crude summary of a much more subtle argument, but it will do for now.)

The same goes for Reppert’s various versions of the Argument from Reason. In none of Plantinga and Reppert’s arguments does this unavoidable assumption — that our capacity for philosophical reasoning is generally reliable — feature as an assumption distinctive to the arguments themselves (i.e., in a way that doesn’t apply to philosophical arguments in general).

But the real surprise is that Oppy apparently rejects the assumption. He says it’s obvious (!) that our reasoning capacities are “highly unreliable” in the domain of philosophy. Yet he makes this claim as part of a philosophical rebuttal of Plantinga and Reppert, in the course of a philosophical case for naturalism, in a philosophical book written by a professional philosopher. If our reasoning capacities are highly unreliable in the domain of philosophy, what on earth does Oppy think he’s doing? This isn’t so much cutting the branch you’re sitting on as felling the tree and grinding the stump.

It’s so odd that I feel I must be missing something important.

Still, Oppy’s right about one thing: if our cognitive faculties are the product of undirected naturalistic evolution — which is to say, if evolutionary naturalism is true — then it’s highly unlikely that those faculties are reliable when it comes to philosophical matters. That’s a big problem for philosophical naturalists like Oppy.

All that said, Atheism and Agnosticism is still a useful primer on the subject.

Moral Values and Christian Apologetics

The topic of moral values comes up often in Christian apologetics. For example, Christians will argue that atheists cannot account for moral values or that the moral relativism associated with postmodernism is somehow self-defeating. I’ve noticed that in such discussions there’s often confusion (usually on the part of the non-Christian, but not always) about what we mean when we speak of ‘moral values’. Indeed, the term is often used equivocally, without recognizing that there are at least two meaningful ways in which we can talk about ‘moral values’. My purpose in this post is to explicitly distinguish these two senses and illustrate why it’s so important to keep the distinction clear in apologetic discussions.

There are different ways of drawing the distinction, but here I propose simply to distinguish between Subjective Moral Values (SMVs) and Objective Moral Values (OMVs). Subjective Moral Values are moral values subjectively held by an individual person. For example, we might say that Ben has different moral values than Lisa, if Ben holds to Christian sexual ethics while Lisa does not. Thus Ben values (in a moral sense) certain sexual behaviors differently than Lisa. He makes different moral value judgments about premarital sex, polyamory, etc. Clearly there’s a relativity to this kind of moral value: SMVs are relative to subjects (i.e., the subjects who engage in moral valuation) and thus can vary from person to person.

Now contrast SMVs with OMVs. Objective Moral Values are non-subjective moral norms, i.e., moral norms that are independent of subjective factors (beliefs, convictions, preferences, feelings, etc.). OMVs are moral norms that hold regardless of whether anyone knows, believes, or recognizes them as such. People may disagree about what the OMVs actually are, but the vast majority of people take for granted (at least in practice) that there are OMVs. I think most people would recognize parental care for infants as an objective moral norm. Parents ought to care for their infant children. Even if every human being became infected with a virus which caused a kind of moral insanity, such that everyone became convinced that parents ought to neglect and abuse their children, it would still be objectively the case that parents ought to care for their children. Such a virus would disrupt our SMVs, but OMVs would be unchanged. Indeed, OMVs couldn’t be affected by a mind-altering virus, precisely because OMVs are by nature non-subjective; they’re independent of subjective mental states.

So why is the distinction between SMVs and OMVs important in Christian apologetics? Let me give two illustrations.

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The Atheist’s Guide to Reality

The following is the unabridged version of a review published in the Christian Research Journal 36:3 (2013). Thanks to CRI for permission to post it here.

Christian philosophers have been developing and refining arguments for the existence of God since the earliest times, but it’s not often one comes across a convinced atheist making a powerful philosophical case for the existence of God. Yet that’s precisely what we find—quite contrary to the author’s intent—in Alex Rosenberg’s book The Atheist’s Guide to Reality.

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The Sting of Death

Death is the theme of the most recent issue of Philosophy Now. Two of the main articles debate whether it would be a good thing for scientists to overcome death. Nick Bostrom’s “The Fable of the Dragon-Tyrant” argues with vigor that death isn’t something we should “gracefully accommodate”. Technology to retard the aging process, and perhaps even to halt and reverse it, may well be within the grasp of this generation, and scientists should make it a priority to pursue such technology. We have “compelling moral reasons to get rid of human senescence.” On the other side, Mary Midgley argues that the promise of endless life is a poisoned chalice: the cost of prolonging our lives would outweigh the benefits.

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