Plantinga on the Alleged “Irrationality” of Atheism

Alvin Plantinga

I want to comment on Gary Gutting’s recent interview of Alvin Plantinga in the New York Times. Unless otherwise indicated, the quotations are quotations of Plantinga.

Still, that’s not nearly sufficient for atheism. In the British newspaper The Independent, the scientist Richard Dawkins was recently asked the following question: “If you died and arrived at the gates of heaven, what would you say to God to justify your lifelong atheism?” His response: “I’d quote Bertrand Russell: ‘Not enough evidence, God! Not enough evidence!’” But lack of evidence, if indeed evidence is lacking, is no grounds for atheism. No one thinks there is good evidence for the proposition that there are an even number of stars; but also, no one thinks the right conclusion to draw is that there are an uneven number of stars. The right conclusion would instead be agnosticism.

In the same way, the failure of the theistic arguments, if indeed they do fail, might conceivably be good grounds for agnosticism, but not for atheism. Atheism, like even-star-ism, would presumably be the sort of belief you can hold rationally only if you have strong arguments or evidence.

1. Unlike some people who identify as atheists, I’m fine with joining Plantinga in defining atheism as the belief that there is no God. Notice, however, that there is an equivocation or, at least, a sort of ‘translation error’ here on Plantinga’s part. What Plantinga seems to forget is that many of the people who identify as atheists don’t use the definition of atheism Plantinga (and I) do; they define atheism as merely the lack of belief that God exists. As such, they are precisely what Plantinga would call an agnostic. So when those people say “the lack of evidence for theism is justification for atheism,” they are NOT saying “the lack of evidence for God’s existence is evidence against God’s existence.” Rather, they are are saying, “the lack of evidence for God’s existence is justification for lacking the belief that God exists.”

2. On the other hand, there are some atheists who indeed do argue that the lack of evidence for God’s existence is evidence against God’s existence. Atheist philosopher Theodore Drange calls that argument the “lack of evidence argument” (LEA). Drange has refuted that argument; I join both Plantinga and Drange in rejecting it.

3. While I agree that atheism (the belief that God does not exist version) does have a burden of proof, atheism doesn’t have nearly the same burden of proof as theism. Why? Because theism has a lower prior probability than naturalism and naturalism entails atheism. This contradicts Plantinga’s claim, “Atheism, like even-star-ism, would presumably be the sort of belief you can hold rationally only if you have strong arguments or evidence” (my italics).

The so-called “problem of evil” would presumably be the strongest (and maybe the only) evidence against theism. It does indeed have some strength; it makes sense to think that the probability of theism, given the existence of all the suffering and evil our world contains, is fairly low. But of course there are also arguments for theism. Indeed, there are at least a couple of dozen good theistic arguments. So the atheist would have to try to synthesize and balance the probabilities. This isn’t at all easy to do, but it’s pretty obvious that the result wouldn’t anywhere nearly support straight-out atheism as opposed to agnosticism. (emphasis mine)

1. The text I have italicized and boldfaced is ridiculous. His “two dozen or so” theistic arguments, philosophically speaking, consist of practically everything but the kitchen sink as evidence for theism. When it comes to arguments for atheism, however, he writes as if the argument from evil is the only argument for atheism (or, at least, the only argument for atheism that provides evidence against theism.) This reeks of a double standard. Plantinga knows very well that atheists have offered serious arguments for naturalism (which entails atheism), including the argument from nonculpable nonbelief (aka “divine hiddenness”), the evidential argument from biological evolution, and the evidential argument from mind-brain dependence. Once we consider the total evidence, it’s far from obvious that it ‘nearly supports straight-out theism as opposed to agnosticism.’

2. Indeed, this paragraph is notable for the fact that it refers to one or more arguments which commit the fallacy of understated evidence. By way of review: in the context of arguments for theism and against naturalism, proponents of a theistic argument are guilty of this fallacy if they “successfully identify some general fact F about a topic X that is antecedently more likely on theism than on naturalism, but ignore other more specific facts about X, facts that, given F, are more likely on naturalism than on theism.” (More on that in a moment.)

I should make clear first that I don’t think arguments are needed for rational belief in God. In this regard belief in God is like belief in other minds, or belief in the past. Belief in God is grounded in experience, or in the sensus divinitatis, John Calvin’s term for an inborn inclination to form beliefs about God in a wide variety of circumstances.

1. As Paul Draper has argued, “if theism does make it likely that some human beings have a properly functioning sensus divinitatis, then it makes it likely that everyone has one or at least that everyone who is not resistant to belief in God has one, which, pace John Calvin, is not what we observe.”

2. Furthermore, as Draper goes on to point out,

… the cognitive science of religion is not wholly supportive of Plantinga’s position. Human beings instinctively believe in all sorts of invisible agents, not just in gods and certainly not just in a single creator-God let alone the specific creator-God of metaphysical theism. So we seem to have a broad sensus actoris instead of a narrow sensus divinitatis. (Cognitive scientists sometimes use the term “hyperactive agency detector,” which sounds so much less impressive than a “sensus divinitatis.”) …

3. As Keith Parsons has argued, the non-existence of the sensus divinitatis is evidence for the non-existence of God.

My argument is simple. I think that Alvin Plantinga is right. If God exists, humans will very likely possess a sensus divinitatis, a God-detecting faculty, which, when functioning properly and in the appropriate circumstances, will present us with warrant-basic (both warranted and epistemologically basic) awareness of his existence. If this is so, and if God does exist, then humans, provided that their sinfulness has not impaired the proper functioning of their sensus, will have a warrant-basic awareness of God’s existence. On the other hand, if there is no God, it is extremely unlikely that humans would possess a cognitive faculty that would produce the warranted (but false) belief that God exists. In this case, evidence that belief in God is not caused by a warrant-conferring cognitive faculty, but rather is generated by a noncognitive process that does not confer warrant on that belief, will, ipso facto, constitute evidence against the existence of God. An atheological argument can therefore be set out semi-formally like this:

1) If God exists, then humans very likely possess a sensus divinitatis, a cognitive faculty which, when functioning properly and in the appropriate circumstances, produces the warrant-basic belief that God exists.

2) If there is no sensus divinitatis, then God probably does not exist, unless the background probability of his existence is very high.

3) It is not the case that the background probability of God’s existence is very high.

4) There is no sensus divinitatis.

5) Therefore, God probably does not exist.

Let’s move on and return to quoting Plantinga.

One presently rather popular argument: fine-tuning. Scientists tell us that there are many properties our universe displays such that if they were even slightly different from what they are in fact, life, or at least our kind of life, would not be possible. The universe seems to be fine-tuned for life. For example, if the force of the Big Bang had been different by one part in 10 to the 60th, life of our sort would not have been possible. The same goes for the ratio of the gravitational force to the force driving the expansion of the universe: If it had been even slightly different, our kind of life would not have been possible. In fact the universe seems to be fine-tuned, not just for life, but for intelligent life. This fine-tuning is vastly more likely given theism than given atheism.

This would be exhibit A of the fallacy of understated evidence in Plantinga’s interview. For the sake of argument, let’s grant that cosmological fine-tuning is evidence for theism over naturalism (and hence atheism). Given that the universe is fine-tuned, however, there are three more specific facts which favor naturalism over theism. First, the only intelligent life we know of is human and it exists in this universe. As Paul Draper explains:

“while it may be true that on single-universe naturalism the existence of anything as impressive as human beings is very unlikely, it is also true that on theism the existence of intelligent beings as unimpressive and flawed as humans is very unlikely. Further, given that human beings do exist, it is certain on single-universe naturalism, but not on theism, that they exist in this universe (i.e., in the one universe that we know to exist).”

Second, intelligent life is the result of evolutionGiven that intelligent life of some sort exists in some universe, the fact that it developed as a result of biological evolution is more probable on naturalism than on it is on theism.

Third, so much of the universe is hostile to lifeGiven that intelligent life of some sort exists in some universe, the fact that so much of our universe is highly hostile to life–such as containing vast amounts of empty space, temperatures near absolute zero, cosmic radiation, and so forth–is more probable on naturalism than it is on theism.

The upshot is this. Even if the general fact of cosmic “fine-tuning” is more probable on the assumption that theism is true than on the assumption that naturalism is true, there are other, more specific facts about cosmic “fine-tuning,” facts that, given cosmic “fine-tuning,” are more likely on naturalism than on theism. Once all of the evidence about cosmic “fine-tuning” has been fully stated, it’s far from obvious that facts about cosmic “fine-tuning” favor theism over naturalism.

Some atheists seem to think that a sufficient reason for atheism is the fact (as they say) that we no longer need God to explain natural phenomena — lightning and thunder for example. We now have science.

As a justification of atheism, this is pretty lame. We no longer need the moon to explain or account for lunacy; it hardly follows that belief in the nonexistence of the moon (a-moonism?) is justified. A-moonism on this ground would be sensible only if the sole ground for belief in the existence of the moon was its explanatory power with respect to lunacy. (And even so, the justified attitude would be agnosticism with respect to the moon, not a-moonism.) The same thing goes with belief in God: Atheism on this sort of basis would be justified only if the explanatory power of theism were the only reason for belief in God. And even then, agnosticism would be the justified attitude, not atheism.

What is lame is Plantinga’s rather uncharitable representation of the evidential argument from the history of science. The explanatory success of non-lunar explanations for lunacy is not greater (or, at least, not significantly greater) on the assumption that a-moonism is true than on the assumption that moonism true. In contrast, the explanatory success of naturalistic explanations is antecedently more likely on naturalism than on theism.

Thomas Nagel, a terrific philosopher and an unusually perceptive atheist, says he simply doesn’t want there to be any such person as God. And it isn’t hard to see why. For one thing, there would be what some would think was an intolerable invasion of privacy: God would know my every thought long before I thought it. For another, my actions and even my thoughts would be a constant subject of judgment and evaluation.

1. This ignores the evidence from the testimony of other atheists, including myself, who say that they wish that theism were true.

2. Even with Nagel, his hope that atheism is true doesn’t entail or make probable that his reasons for atheism are wrong. Consider an analogy. A Holocaust survivor hopes that what the Nazis did was morally wrong, but no one would argue that the Holocaust survivor is incorrect simply because they hoped that the Nazis were morally wrong.

3. It gets worse. To see why, let’s do a thought experiment. Suppose you are arrested, put on trial, convicted for a crime you did commit, and are sentenced to prison. You probably wouldn’t say to yourself, “Well, I don’t want to live as if I am going to prison, so I’m going to invent a bunch of arguments in order to justify the belief that I am not going to prison.” While it’s possible that someone might do that, probably virtually everyone would accept the reality that they are going to prison. To be sure, they might complain about things (such as the fairness of the law, the judge, or the sentence), but they wouldn’t deny the reality that they were going to prison.

4. Besides, Plantinga’s dismissive attitude towards the reasons why atheists are atheists just assumes that all atheists want to “live as if God does not exist” and that desire outweighs any other desires atheists might have. So far as I can tell, that assumption is false. First, though I don’t have the data to back this up, I suspect that even most atheists wish that some sort of life after death is true. (They may not want to live forever and they may want a different kind of afterlife than the one offered by Christianity, but that’s beside the point.) And any sane, rational person desires to avoid torture, especially eternal torture in Hell. It’s not obvious why anyone should think that those desires would always be outweighed by the desire to “live as if God does not exist.”

Evolution will have resulted in our having beliefs that are adaptive; that is, beliefs that cause adaptive actions. But as we’ve seen, if materialism is true, the belief does not cause the adaptive action by way of its content: It causes that action by way of its neurophysiological properties. Hence it doesn’t matter what the content of the belief is, and it doesn’t matter whether that content is true or false. All that’s required is that the belief have the right neurophysiologicalproperties. If it’s also true, that’s fine; but if false, that’s equally fine.

Evolution will select for belief-producing processes that produce beliefs with adaptive neurophysiological properties, but not for belief-producing processes that produce true beliefs. Given materialism and evolution, any particular belief is as likely to be false as true.

This is Plantinga’s well-known “Evolutionary Argument Against Naturalism” (EAAN).

1. The basic problem with the argument is that it’s false that “Given materialism and evolution, any particular belief is as likely to be false as true.” Rather, as Draper pointed out in his debate with Plantinga, “More generally, the long term survival of our species is much more to be expected if our cognitive faculties are reliable than if they are unreliable, and that entails that the long term survival of our species is strong evidence for R.”

2. Furthermore, “In addition, it is very unlikely that belief-producing mechanisms that do not track the truth would systematically promote survival in a very diverse and often rapidly changing environment.”