Plantinga's Evolutionary Argument Against Naturalism

[nightbringer]

I'm not sure if Plantinga has presented this argument in standard essay form but he gave it at a lecture at Biola University. You can listen to it here and read an outline of it here.

He argues that the probablity of our cognitive faculties being reliable (i.e. prone to reliably producing true beliefs) is low or inscrutable given naturalistic evolution. He therefore concludes that one cannot rationally accept evolution and naturalism. I think it's an interesting argument but I'd like to hear counter-responses before I make a strong judgment on it either way.

I think Plantinga rightly concludes that for any particular scenario relevant to the survival of an organism, there can be a number of false beliefs which still produce advantageous behaviour. But I think in the long run, cognitive faculties which produce true beliefs will output the correct survival behaviour more often and will thus ultimately be selected for. A possible response to this would be that we simply don't know whether such faulty cognitive faculties have been weeded out yet and thus we might ourselves have a faulty one.

What are your thoughts?

[robto]

nightbringer, I think your response is exactly right.

Moreover, Plantinga's version doesn't take into account those instances in which our perceptions are not reliable: optical illusions, mirages, and so forth.

For example, picture a spear-fisherman by the side of a river. Because of the refraction of light, he doesn't see the fish where it actually is, he sees it displaced from its true location and has to learn to compensate for the illusion when he makes his jab with the spear.

Wouldn't it be more conducive to his long-term survival if he could perceive where the fish actually is? Of course it would! But evolution has no means of producing such a perception: we see what the light brings to our eyes, nothing more or less.

On the other hand, God can do anything. Why didn't God provide us with true perception in such situations?

In short, the evolutionary view offers an explanation of why it is possible for our senses to be fooled. The theistic view does not.

[Seasanctuary]

Darn. You two already gave both parts of my answer.

[nightbringer]

nightbringer, I think your response is exactly right.

Moreover, Plantinga's version doesn't take into account those instances in which our perceptions are not reliable: optical illusions, mirages, and so forth.

For example, picture a spear-fisherman by the side of a river. Because of the refraction of light, he doesn't see the fish where it actually is, he sees it displaced from its true location and has to learn to compensate for the illusion when he makes his jab with the spear.

Wouldn't it be more conducive to his long-term survival if he could perceive where the fish actually is? Of course it would! But evolution has no means of producing such a perception: we see what the light brings to our eyes, nothing more or less.

On the other hand, God can do anything. Why didn't God provide us with true perception in such situations?

In short, the evolutionary view offers an explanation of why it is possible for our senses to be fooled. The theistic view does not.

I see that you are trying to turn the scenario around, such that, given that our cognitive faculties do not always produce true beliefs, naturalism better accounts for these faculties than theism. My response to this argument would depend on what exactly you are claiming. Seems to me that you are either claiming that our cognitive faculties are naturally inclined towards some level of malfunction, or that our cognitive faculties are not the best that they could be.

The first claim depends on our account of rationality. If we take Plantinga's account, where a belief is warranted when it is produced by an agent S's properly functioning cognitive faculties aimed at producing true beliefs, in an environment where said properly functioning cognitive faculties are designed to function, it is not so much that the fisherman has a bad design plan, it is just that he is not in an environment where his faculties are particularly useful for producing true beliefs. We can say that under these conditions his natural beliefs as to the location of the fish have little warrant. We should note though that it isn't like the fisherman completely lacks the cognitive faculties for producing true beliefs here - he simply has to work a bit harder to arrive at the truth.

Why should God create him such that he requires this additional effort? Well, I consider these sort of objections akin to the sort that God should have created us with four arms rather than two because it would make our lives easier. I see no reason why God should be committed to making us the best possible being that we could be.

[nightbringer]

Also here is a debate between Plantinga and Draper over the argument. It's relatively recent so it should do a good job of reflecting Plantinga's current thoughts on the arguments. I haven't read it yet but it looks juicy!

[lao tzu]

I really don't understand where Plantinga is trying to go with this. If we evolved, then certainly there could be false beliefs inherent in our reasoning. How he arrives at the idea that this is specifically an issue for the naturalist is beyond me. If we evolved, this is just as much an issue for the supernaturalist, with all of the additional pitfalls of supernaturalism still in place.

As ever, Jesse

[nightbringer]

The advantage theistic evolution has here is that God can orchestrate the evolutionary processes toward goals which wouldn't be attainable, or would be unlikely to be attainable, given purely naturalistic evolution. So what is improbable on naturalistic evolution is not necessarily so for theistic evolution.

[lao tzu]

The advantage theistic evolution has here is that God can orchestrate the evolutionary processes toward goals which wouldn't be attainable, or would be unlikely to be attainable, given purely naturalistic evolution. So what is improbable on naturalistic evolution is not necessarily so for theistic evolution.

Casual observation is sufficient to show that humans do make decisions based on false beliefs. So if there is a god capable of orchestrating evolutionary processes to make it otherwise, such god has once again passed up an opportunity to provide evidence for its existence.

As mentioned by others above, naturalism predicts this state of affairs where theistic evolution merely allows it, and would be just as comfortable allowing its contradiction.

As ever, Jesse

[nightbringer]

Casual observation is sufficient to show that humans do make decisions based on false beliefs. So if there is a god capable of orchestrating evolutionary processes to make it otherwise, such god has once again passed up an opportunity to provide evidence for its existence.

Already tackled this objection. But at any rate it isn't terribly relevant to the matter at hand. Plantinga's argument is against naturalism, not for theism necessarily though Plantinga does of course believe that theism is the more reasonable alternative.

As mentioned by others above, naturalism predicts this state of affairs where theistic evolution merely allows it, and would be just as comfortable allowing its contradiction.

As ever, Jesse

Does naturalistic evolution predict that we will make false beliefs? Imagine an intelligent species not unsimilar to ourselves, living on some other world. Imagine they are similar to us except for the fact that they never produce false beliefs. Given this state of affairs would you say it is impossible that these creatures came about through broadly evolutionary means? I suspect you would say that it is still possible. Therefore false beliefs are not a necessary prediction of evolutionary naturalism.

In actual fact if Christian theism were true we would expect people to have some false beliefs because it would be true that we all have a sinful nature and of course it is true that selfish desires can distort our beliefs. For instance, I can think so highly of myself that I erroneously think that everyone considers me an absolute philosophical genius.

[showmeproof]

I'm not sure if Plantinga has presented this argument in standard essay form but he gave it at a lecture at Biola University. You can listen to it here and read an outline of it here.

He argues that the probablity of our cognitive faculties being reliable (i.e. prone to reliably producing true beliefs) is low or inscrutable given naturalistic evolution. He therefore concludes that one cannot rationally accept evolution and naturalism. I think it's an interesting argument but I'd like to hear counter-responses before I make a strong judgment on it either way.

I think Plantinga rightly concludes that for any particular scenario relevant to the survival of an organism, there can be a number of false beliefs which still produce advantageous behaviour. But I think in the long run, cognitive faculties which produce true beliefs will output the correct survival behaviour more often and will thus ultimately be selected for. A possible response to this would be that we simply don't know whether such faulty cognitive faculties have been weeded out yet and thus we might ourselves have a faulty one.

What are your thoughts?

Evolution can, and has, been verified regardless of any philosophical argument. He can present arguments if he likes, but there is this thing called DNA. I'm always confused why people turn towards philosophy to 'disprove' evolution.

[nightbringer]

He isn't disproving evolution. He is trying to say that one cannot rationally hold to evolution AND naturalism at the same time. Whether the argument is successful or not is the topic of this thread.

[element771]

Evolution can, and has, been verified regardless of any philosophical argument. He can present arguments if he likes, but there is this thing called DNA. I'm always confused why people turn towards philosophy to 'disprove' evolution.

That is not the point...

He is not trying to disprove evolution. He is merely trying state the evolution is not concerned with forming reliable truth forming beliefs.

[Child_Of_Wisdom]

If evolution and naturalism are true then the purpose of our cognitive faculties(if they do indeed have a purpose) is not to provide us with true beliefs. The only thing evolution guarantees if anything is that our behavior increased the likelihood of survival in the environment our ancestors found themselves in. Most people generally think our beliefs along with our desires determine our behavior however this is not a given. If materialism is true and consciousness is an just an emergent phenomenon then belief is a long standing biochemical neural event that happens to point at some abstract thought. However there need not be any causal efficacy between the abstract thought this biochemical neural event points to and the behavior that follows as an inevitable consequence within the chain of biochemical reactions.

So assuming epiphenomenalism is true the propositional content of our belief is irrelevant to evolution. If belief does not cause behavior then evolution is blind to beliefs and cannot shape them. Even if beliefs and desires do effect our behavior the beliefs need not be true. There are many illogical combinations of beliefs, desires and behaviors that would still result in survival.

[showmeproof]

That is not the point...

He is not trying to disprove evolution. He is merely trying state the evolution is not concerned with forming reliable truth forming beliefs.

Hmm lets think about that one real quick. Say you have a week old Ibex on the rocky crags in Israel being hunted by a fox do you think that the ability to judge the steepness of a cliff, the presence of loose gravel, the ability to discern motive and projection of possible counter-moves are of benefit for the survival of either party?

If either the Ibex or the Fox misjudge one of any number of variables it could mean its life. The week old Ibex correctly believes the fox is a threat and bolts immediately...is that not useful to survival...does that not demonstrate the utilization of 'reliable truth forming beliefs'?

The problem is in the question you have raised. Evolution is not concerned with anything. The Ibex is very concerned in keeping its life and the fox is very concerned about its next meal. It is a misunderstanding to read intent behind a natural process such as evolution.

[MaxVel]

I think you're missing the point of Plantinga's argument...

Hmm lets think about that one real quick. Say you have a week old Ibex on the rocky crags in Israel being hunted by a fox do you think that the ability to judge the steepness of a cliff, the presence of loose gravel, the ability to discern motive and projection of possible counter-moves are of benefit for the survival of either party?

If either the Ibex or the Fox misjudge one of any number of variables it could mean its life. The week old Ibex correctly believes the fox is a threat and bolts immediately...is that not useful to survival...does that not demonstrate the utilization of 'reliable truth forming beliefs'?

Not necessarily.

Plantinga's argument is that evolution selects for behaviours that promote survival. If the week old Ibex behaves in the right way it has an increased chance of survival. The process of evolution 'doesn't care' what the Ibex believes. Any belief - true or not - that produces behaviour that enhances the survival chances of the Ibex is going to be selected for. Say the Ibex believes that the fox creeping up wants to make it eat some bad-tasting food, and so it bolts because it doesn't like the idea of eating the bad-tasting food, does evolution 'care'? Plantinga says 'No'. The false belief produces a survival-enhancing behaviour and so is selected for.

Bottom line: Plantinga's argument suggests that, if evolution is true, and if naturalism is true (i.e. evolution is not guided by God), then the probability of our beliefs being true ones is low.

The problem is in the question you have raised. Evolution is not concerned with anything. The Ibex is very concerned in keeping its life and the fox is very concerned about its next meal. It is a misunderstanding to read intent behind a natural process such as evolution.

Exactly. Which is why we have little reason to think that unguided evolution has selected for creatures with true beliefs. It selects for creatures with behaviour that enhances their chances of survival. The beliefs that drive that behaviour are effectively invisible to evolution.