Are Alvin Plantinga and his frog on to something?

Replies to This Discussion

Permalink Reply by James Croft on November 13, 2010 at 17:22

It's quite obviously nonsense, as the process of evolution would select for advantageous adaptations, and more accurate beliefs are clearly a beneficial adaptation in many cases. Even the cognitive deficits we now understand we have (such as confirmation biases, logarithmic understandings of number, and misapprehensions of probability) clearly served a beneficial adaptive function in our evolutionary past. So, the problem with the argument, as Stephen pointed out, is in the first premise, which is obviously and demonstrably false - evolutionary mechanisms quite clearly would select for truer over less true beliefs.

Plantinga's "Frog Response" - that the frog's neurology "accurately indicates" the position of passing flies, but whether the belief content is true or false is irrelevant to the frog, is clearly inadequate, because if the neurological system is "accurately indicating" the position of the fly, then it seems not unreasonable to conclude that the frog does indeed have "true belief" regarding the position of the fly.

What Plantinga tries to do here is smuggle in a form of mind-body dualism by suggesting that, essentially, whether the frog has any beliefs at all is irrelevant to how it acts, and that adaptive behavior is the only thing that matters. But if that is the case, that defeats the first premise of his own argument, because then the idea that evolution is unlikely to provide us with cognitive mechanisms which give rise to true beliefs (which is his first premise) reduces to "evolution is unlikely to promote adaptive behavior", which is obviously false.

So he is trying both to embrace mind-body dualism with his frog analogy, and reject it with his first premise. If he seeks to avoid this contradiction, he either has to ditch the frog analogy (and then Laws' critique - that evolution would select for truer beliefs) stands undefeated), or reject the first premise of his argument, in which case he has nothing at all.

This is enough to defeat his argument, but if it were not, there is the not insignificant problem that he seems to assume that our cognitive faculties are either totally reliable or totally unreliable. Well, we know for a fact they aren't totally reliable, so we shouldn't be forced into defending that position. We have, as I've already pointed out, a number of cognitive deficiencies that we should be aware of. These deficiencies make perfect sense when seen in an evolutionary context, but none at all if we are indeed the product of a perfect designer (this is true of physical as well of cognitive characteristics, incidentally).

This false dichotomy also hides the possibility that through evolution organisms could adapt progressively better cognitive mechanisms, without ever having to achieve perfect truth-giving capability or falling into total randomness (which would be the worst conceivable outcome).

There are many other problems too, but those are quite enough to demolish the argument.

Permalink Reply by James Croft on November 13, 2010 at 17:40

I should also add, just as with the presuppositional argument, even if we accept Plantinga's position, it simply means we couldn't trust our reasoning regarding God either. It's not at all a convincing or self-consistent or fruitful or even interesting argument.

Permalink Reply by Steven Carr on November 13, 2010 at 18:29

'It seems to hinge on the idea that the probability of evolution on a naturalistic framework is unlikely to produce reliable cognitive faculties.'

That's strange.

Christians like Simon Conway Morris say it is 'inevitable' that evolution will produce reliable cognitive faculties.

Mind you, if Plantinga is correct then we would expect very few species indeed out of the billions that have existed to have developed reliable cognitive faculties.

Assuming naturalism is true, then Plantinga can show that human like species are extremely rare.

'Without God as guarantor of our perceptions and cognitive faculties we have no way of knowing that our beliefs are true.'

God guarantees that my belief there is no god is true? How does that work then?

Permalink Reply by Steven Carr on November 13, 2010 at 18:30

Plantinga argues that there are demons who are highly motivated to attack his reasoning and senses and perfectly capable of doing so.

As Plantinga cannot know if his reasoning has been attacked by demons, the best thing to do is ignore somebody who cannot even know he is thinking straight.

Permalink Reply by Steven Carr on November 13, 2010 at 18:35

'It seems to hinge on the idea that the probability of evolution on a naturalistic framework is unlikely to produce reliable cognitive faculties'

Is that why people go to universities to study evolution and science, rather than rely on their instincts?

How did differential calculus develop?According to Plantinga, as differential calculus evolved through natural selection, we should not trust.

Misguided historians claim Newton and Leibniz developed calculus , but we know this is not true. Plantinga claims that if naturalism is true, then beliefs evolve through natural selection,and there is no other possible mechanism, such as science or research, to develop beliefs.

Permalink Reply by Imago Dei on November 13, 2010 at 20:07

As a Christian I take no notice of Plantinga who argues for a godofthegaps

Permalink Reply by Paul S. Jenkins on November 13, 2010 at 20:51

It's quite obviously nonsense, as the process of evolution would select for advantageous adaptations, and more accurate beliefs are clearly a beneficial adaptation in many cases.

For me, that says it all.

I was looking forward to this Unbelievable? discussion as I had already tried — and failed — to get to grips with "CONTENT AND NATURAL SELECTION" and also Warrant and Proper Function. I could not get beyond the first premise: that "accepting naturalism and evolution entails that the probability that our beliefs are true is low". Stephen Law rightly questioned this premise, on which the rest of the EAAN is based.

Since first encountering the EAAN (in this forum, incidentally) I've wondered why it's not discussed more. Now I know.

Permalink Reply by Justin Brierley on November 13, 2010 at 21:36

Seems to me that Plantinga was very careful to precisely not do that when i asked him about whether he supports ID?

Permalink Reply by Imago Dei on November 13, 2010 at 21:56

P is clearly godofthe gaps as when he argued that if a scientist cannoit explain soemething then it is reasonable to conclude goddidit i.e. by intervention

In this paper http://www.leaderu.com/orgs/arn/odesign/od182/methnat182.htm#anchor...

he says

So there is little to be said for methodological naturalism. Taken at its best, it tells us only that Duhemian science must be metaphysically neutral and that claims of direct divine action will not ordinarily make for good science. And even in these two cases, what we have reason for is not a principled proscription but a general counsel that in some circumstances is quite clearly inapplicable. There is no reason to proscribe questions like: did God create life specially? There is no reason why such a question can't be investigated empirically63; and there is no reason to proscribe in advance an affirmative answer.

and footnote 63
63. Why couldn't a scientist think as follows? God has created the world, and of course has created everything in it directly or indirectly. After a great deal of study, we can't see how he created some phenomenon P (life, for example) indirectly; thus probably he has created it directly.

That is simply godofthegaps

I have noticed this type of things in his other writings

Permalink Reply by John Fraser on November 13, 2010 at 23:56

James,

So, the problem with the argument, as Stephen pointed out, is in the first premise, which is obviously and demonstrably false - evolutionary mechanisms quite clearly would select for truer over less true beliefs.

I haven't listened to the program yet, but I am quite familiar with the argument. I think you're making a mistake in talking about evolution selecting for beliefs. A belief is not something that can be selected by natural selection. Rather, Plantinga's argument has to do with the mechanisms that form beliefs.

But I think you're also missing something when you say that more accurate beliefs are beneficial in many cases. While that might be true, it isn't necessarily true, and therein lies the problem. What that means is that we can't know whether or not our belief-forming faculties are reliable, because we're relying on those very faculties to make the assessment. I think Plantinga's argument is strengthened by the fact that most people believe in the supernatural. Yet if naturalism is true, this is a false belief. So here evolution has selected for mechanisms which produce (according to the naturalist) a false belief about the fundamental nature of reality. On what basis, then, can the naturalist say that in HIS case, those belief-forming faculties have produced a true belief?

Permalink Reply by John Fraser on November 13, 2010 at 23:58

James,

I should also add, just as with the presuppositional argument, even if we accept Plantinga's position, it simply means we couldn't trust our reasoning regarding God either.

This is a very peculiar response I must say. In fact, the whole point if Plantinga's argument is successful (which I think it is) is that the theist is not burdened by the problem faced by the naturalist. In other words, it's only if naturalism is true that we can't trust our belief-forming faculties. If theism is true, this does not obtain. Thus your complaint here is off base.

Permalink Reply by John Fraser on November 14, 2010 at 0:04

Justin,

Dare I say it, it has echoes of the presuppositional argument.

Yes and no. The difference is that it isn't trying to argue that God is necessary for logic and rationality, rather that naturalism doesn't have a good account for reliable belief-forming mechanisms and thus leaves us in the lurch epistemically speaking. So there are some similarities, but some important differences also. It might be more of a form of inference to the best explanation.

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