Alvin Plantinga on naturalism
Alvin Plantinga is a Christian philosopher at the university of Notre Dame. He’s best known for his Reformed Epistemology and his explanation of the problem of evil. Here’s a lecture by him.
In his book Warrented Christian Belief, Plantinga argues that if naturalism and evolution are true, then there is no reason to be sure that our minds are reliable devices for giving us accurate information. He nicknames his argument “Darwin’s Doubt.” Darwin once said,
With me, the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy. Would anyone trust in the convictions of a monkey’s mind…?
Naturalism argues that this world has only natural causes. There is no mind or consciousness that planned this world or designed it. It’s purely an accident. And in evolution, there are only three things that our brains are needed for– “feeding, fighting, and reproducing.” Accurate knowledge outside of those three things isn’t needed for survival. So if naturalistic evolution is true, we have no way of knowing if our minds are reliable at giving us the truth. Would you trust something that developed by accident?
Here’s a Wikipedia article on Plantinga’s argument.
Anchor for the Soul 
Plantinga is great.
That certainly is an insightful argument from Plantinga, but it’s one that’s been understood since Plato. His allegory, “The Cave,” asks just that question, of whether our minds are reliable at giving us the truth – can our senses be trusted? It’s a deep philosophical question, but not one that means much, unless you’re suggesting that airplanes don’t really fly, the internet really enable communication, 2+2=4, etc.
Dan,
I checked out your blog. It looks like you have quite a bit of experience with science.
Don’t you think that the scientific method assumes that our brains work in a rational manner (i.e. they give us fairly reliable information)?
Yes, the scientific method does assume that we are capable of reason.
You note above that that evolutionarily-speaking, brains serve only to enable “feeding, fighting, and reproducing.” I would agree with that also, and extend it to suggest that there is quite a lot of brainpower that can be put into those behaviors, to control an extremely wide array of activities. These behaviors and mental capacities might include “rationality,” were they developed to a sufficient extent, wouldn’t you say?
But could the brain develop in such a matter that ensured that our scientific reasoning is actually reliable?
I’m not so sure. If anything, I think that naturalism leaves us questioning if in reality our brains give us accurate information about the world?
I mean we don’t necessarily need complex scientific information in order to eat, have sex, and kill things.
That’s true, questioning our own accuracy is a smart way to go. But it’s also reasonable to assume certain things to be factual and truthful – this falls under deductive reasoning, I would say, as we deduce that something is real with a very high level of certainty. For example, as I mentioned, I’m pretty sure that airplanes really do fly and microprocessors really do make my PC function properly. There are plenty of other examples out there, of things that most people would think absurd to ask “but is that real?”
So, can our humble intellects be trusted on the matter of evolution and biology? I think so. Granted, there are assumptions that are involved, such as “how do we know that radiocarbon dating is accurate?,” but most of those things can be independently confirmed.
And while you’re right, we don’t necessarily need science to eat, have sex and kill things, it certainly appears to help.
When you say, “Most of those things can be independently confirmed,” do you mean through a way outside of science? I’m not sure that I follow you there.
Deductive reasoning is problematic since it doesn’t tell anything new about the world. It’s just an equals sign. 2+2=4. Cars are automobiles (i.e. that’s the definition of a car). In other words, a priori reasoning has its limits.
Plantinga’s whole argument has revealed the limits of inductive reasoning.
It seems to me that you’re making a place for intuition within your epistemology. But is there a solid place for intuition within a naturalistic worldview?
Oops! I’m sorry to assume that you’re a naturalist. I don’t really know if that’s the case.
On independent confirmation, no, I mean a way through using alternative approaches within science. For instance, using calibrated molecular phylogenies to confirm the fossil record, which was in turn measured by radiocarbon dating, among other methods. To bring this into question is to question our ability to know anything, period, which I think is unreasonable, seeing how so much of our current science and technology consistently and accurately functions as we expect it should.
Yes, there are both elements of inductive and deductive reasoning in there – both assumptions that “it works, therefore it’ll keep working,” as well as the deduction of how things work as compared with positive and negative experimental controls, which are certainly not based upon a priori reasoning.
So, Plantinga is right, inductive reasoning most definitely has its limits. But deductive reasoning, the scientific method, experimental confirmation of hypotheses, etc., more than compensate, I think. Formulating hypotheses is a bit of an intuitive art, but the confirmation or refutation of hypotheses is not.
And yes, I would accept being described as a naturalistic thinker.