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#708 Plantinga’s EAAN Once More

November 15, 2020
Q

Dr. Craig,

I need help with Alvin Plantinga's evolutionary argument against naturalism. Since I discovered it, I fell in love with the argument; the idea that "it is irrational to believe in naturalism, whether it is true or not" left me shocked. However, reflecting on the argument I have come to think that, even if it is solid, the argument turns out to be self-destructive (just what he is trying to prove about naturalism!)

1. P (R| N&E) is low.

2. Anyone who accepts (believes in) N&E and considers P (R | N&E) to be low has a defeatist (defeatist) for R.

3. Anyone who has a defeater for R has a defeater for any other belief he has, including N&E itself.

4. If a person who accepts N&E acquires a defeater for N&E, [then] N&E is counter-productive and cannot be rationally accepted.

Now, I concede that the premises are true (or more plausible true than false), but I think that the first premise undermines itself. Think about the following: if someone who believes in naturalism and evolution has a defeater for all his beliefs because he accepts (1), then he has a defeater for N&E; however, couldn't the naturalist object that just as he has a defeater for all his beliefs, he also has a defeater for the "P (R | N&E) is low" because, given (1), one cannot trust N&E truth and any other belief? however "P (R | N&E) is low" fits "any other belief". That is, given N&E, our beliefs are not reliable, not even N&E, but our belief in (1) would not be reliable either, and that is the premise that underpins the entire argument. I feel that I am missing something... Could you point me out if I am wrong? I'm sorry if my writing is bad, but that shows how confusing this makes me. God bless you

Israel

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Dr. craig’s response


A

Just last week I discussed Alvin Plantinga’s Evolutionary Argument against Naturalism (EAAN) in QoW #707. There we were able to dismiss fairly quickly some objections based upon misunderstandings of the argument. By contrast, you have correctly understood the argument and identified one of its most paradoxical features.

Although you have stated the argument using symbols, let me post again a formulation of the argument in ordinary prose for those unaccustomed to symbolic arguments. Plantinga’s argument can be simply formulated as follows:[1]

1. The probability that our cognitive faculties are reliable, given naturalism and evolution, is low.

2. If someone believes in naturalism and evolution and sees that, therefore, the probability of his cognitive faculties’ being reliable is low, then he has a defeater for the belief that his cognitive faculties are reliable.

3.  If someone has a defeater for the belief that his cognitive faculties are reliable, then he has a defeater for any belief produced by his cognitive faculties (including his belief in naturalism and evolution).

4.  Therefore, if someone believes in naturalism and evolution and sees that, therefore, the probability of his cognitive faculties’ being reliable is low, then he has a defeater for his belief in naturalism and evolution.

Conclusion: Naturalism and evolution cannot be rationally accepted.

Now you rightly point out that if the naturalist has a defeater for any belief produced by his cognitive faculties, then he has a defeater for (1)—or, for that matter, any of the premisses of the argument or for the conclusion of the argument. So you’re not wrong; but you are missing something. What this shows is that the naturalist is caught in a logical quagmire from which there is no escape by rational thought. He cannot upon reflecting on this argument rationally conclude that naturalism and evolution cannot be rationally accepted and therefore he ought to abandon naturalism. He can’t rationally conclude anything. He is caught in a circle from which there is no means of rational escape.

In preparation for my debate with Erik Wielenberg, in which I presented a form of the EAAN aimed at moral reasoning, I corresponded with Andrew Moon, a brilliant young philosopher who has worked extensively on this argument. Here is how he put it to me:

The way Plantinga sets things up, he has it that the naturalist gets a defeater for R, and hence, for all of her beliefs.  The naturalist is in a state of epistemic disarray.  Interestingly, Plantinga never goes the extra step of saying, “The rational move for the naturalist, then, is to give up N and now think that evolution is guided.  Then all will be made epistemically well.” I think that Plantinga thinks that there is no rational move for the naturalist to make at this point, and he has some funny line where he says, “at this point, the naturalist can be saved only by grace and not works.” (Andrew Moon to William Lane Craig, Oct 11, 2017)

Here once more we see the dazzling genius of Alvin Plantinga. Superficially, we might think that his argument gives the naturalist good reason to abandon naturalism. But paradoxically it doesn’t. It just leaves the naturalist in a self-defeating circle which cannot be exited except by a repudiation of the whole vicious circle.

 

[1] Alvin Plantinga, Where the Conflict Really Lies: Science, Religion, and Naturalism (Oxford: Oxford University Press, 2011), pp. 344-5.

- William Lane Craig