Philosopher Alvin Plantinga made a few quotable points in an interview posted by the New York Times on Sunday.
On the claim that lack of evidence for theism is evidence for atheism:
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.
On whether or not the existence of imperfections in the world is evidence against God:
I suppose your thinking is that it is suffering and sin that make this world less than perfect. But then your question makes sense only if the best possible worlds contain no sin or suffering. And is that true? Maybe the best worlds contain free creatures some of whom sometimes do what is wrong. Indeed, maybe the best worlds contain a scenario very like the Christian story.
Think about it: The first being of the universe, perfect in goodness, power and knowledge, creates free creatures. These free creatures turn their backs on him, rebel against him and get involved in sin and evil. Rather than treat them as some ancient potentate might—e.g., having them boiled in oil—God responds by sending his son into the world to suffer and die so that human beings might once more be in a right relationship to God. God himself undergoes the enormous suffering involved in seeing his son mocked, ridiculed, beaten and crucified. And all this for the sake of these sinful creatures.
I’d say a world in which this story is true would be a truly magnificent possible world. It would be so good that no world could be appreciably better. But then the best worlds contain sin and suffering.
On the atheist argument that “we no longer need God to explain the world”:
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.
On the problem with believing in both materialism and evolution:
[I]f there are only material entities, then atheism certainly follows. But there is a really serious problem for materialism: It can’t be sensibly believed, at least if, like most materialists, you also believe that humans are the product of evolution.... The belief that both materialism and evolution are true...can’t rationally be held.
Read the rest of the interview to find out why.