A lot of atheist arguments focus on the lack of evidence supporting the truth of various religious beliefs. Famous atheist Christopher Hitchens (God rest his soul) is said to have remarked, That which can be asserted without evidence, can be dismissed without evidence. This is a compelling point, but it has important limitations, both logical and practical.
It’s not a bad argument, of course. “Prove it!” is the ultimate objection in lots of situations, from poker to physics. But in some areas of life, it sounds silly. Suppose you said to me, “I’m glad I became a writer instead of a scientist, because I just don’t have what it takes to be a scientist.” If I jumped up and said, “Prove it!” you wouldn’t know quite how to respond. Or suppose you told me, “Most people lose their faith because, when they are children, religion is shoved down their throats.” By saying “Prove it!” I wouldn’t be either refuting your statement or offering you a meaningful opportunity to justify it. Many things in life, even very important things, aren’t susceptible to rigorous proof.
Atheists reject religion for this reason. As I understand it, the lack-of-evidence argument against religion goes something like this:
Assertions about the Universe are true if and only if they are supported by a particular kind of evidence, namely, evidence that can be tested by third parties in standard ways employing the scientific method.
The logical limitations of this argument can be illustrated by focusing on the evidentiary criteria. The argument does not simply require that assertions be supported by “evidence,” but by experimental evidence, the kind of evidence that a scientist relies on when proving or disproving a hypothesis. When that demand is leveled at the religious person, he or she may well respond, “Of course we don’t have the kind of evidence you’re looking for. That’s why it’s called ‘faith,’ dummy!” And this is where the conversation breaks down and people start yelling at each other.
But get ready for a shocker: From the logical point of view, the religious people have the stronger position. The lack-of-evidence argument relies on an a priori exclusion of the particular type of evidence that most strongly supports religious belief, namely, the testimony of witnesses. Religious beliefs are widely supported by evidence of this sort, and the lack-of-evidence argument provides no justification for excluding it. No one would ask us to rely on the patterns in tea leaves, or kinks in goat entrails, as evidence of earthly events. These forms of evidence are inherently unreliable. But there’s nothing inherently unreliable about testimony. That’s why we use it so extensively in courtrooms. By tinkering with the proof requirements, the atheist creates conditions making it impossible for religious people to justify their beliefs. What really hurts is that the atheist then criticizes them for failing to provide a satisfactory justification.
In the context of religion, the testimony of witnesses shouldn’t be rejected out of hand. Christianity, for example, is internally consistent in this regard, because the founder of Christianity insisted we should consider this very type of evidence. Jesus repeatedly exhorts doubters to be persuaded by testimony, e.g. Luke 7:18-23, John 3:10-11, and his followers make the same argument, e.g. 1 Corinthians 15:3-7. And since Jesus lived in an age before video and laboratory instrumentation, the only evidence that survives is the testimony. So the lack-of-evidence argument excludes all the evidence that Christians have.
The real point of Hitchens’ remark is to assert that religion is unsupported by evidence. This assertion is false, and its falsity is (as a philosopher would say) noncontroversial. Religious beliefs are supported by plenty of evidence. Atheists just exclude the evidence from consideration. And they refuse to justify this exclusion. It is an a priori determination, one that does not depend on experience or evidence.
These a priori justifications for atheism crop up all the time. I recently read an atheist’s rebuttal of near-death experiences, where the person experiences a divine presence. The atheist explained the phenomenon thus: It’s basically the synapses of the brain misfiring due to catastrophic trauma to the brain or the debilitating effects of illness. Well, certainly the experience involved synaptic activity in the brain; all consciousness does. But why insist that, in this instance, the synapses were misfiring? After all, lots of terribly injured and ill people continue to accurately perceive what’s going on around them. The atheist believes that this poor chap’s synapses were misfiring, not because of the report of some device that was monitoring brain activity, but because of the appearance of something in which the atheist does not believe: a divine presence.
Similarly, in Fatima, Portugal, in 1917, tens of thousands of people witnessed apparently miraculous events, including a dramatic change in the appearance of the sun, which shined in different colors and then appeared to oscillate and rapidly approach them. The atheist discounts the testimony of these witnesses, offering the explanation that prolonged staring at the sun, coupled with psychological factors, account for the vision. The atheist prefers this explanation, not because of laboratory experiments in which people stared at the sun and reported the same effect, but because the atheist disallows the possibility that any supernatural factors were at work. If the same crowd had witnessed something the atheist does believe in, like a meteor or an archbishop, then their testimony would be evaluated under a different set of rules. Since they saw a miracle, they are credulous peasants who don’t understand the neurology of vision.
The pattern is the same: If someone provides evidence of a supernatural event, the atheist rejects the evidence, because supernatural events are against the atheist’s belief system.
All this tedious logic doesn’t prove that atheists are wrong and religious people are right. But it shows that atheists, like religious people, take some things on faith. Which is not such a bad thing, really.
If you want to delve into this aspect of atheism, I recommend G.K. Chesterton’s entertaining book Orthodoxy, which is continually in print, and which is available for free online at http://www.ccel.org/ccel/chesterton/orthodoxy.html