If Christianity is true, then, of course, the answer has to be, “Yes.” But is it true?
The philosophically significant question, however, is this: “Does naturalism or theism, including Christian theism, provide the best explanation for birth defects?”
Here is an excellent by Paul Draper, taken from a lecture he recently gave at the University of Notre Dame.
[I]magine two alien beings who are much like us in intellectual ability and who are gradually learning everything we know (and nothing more) about our biosphere. To make them even more similar to us, let us also suppose that these two beings know almost nothing about themselves and don’t take into account what they do know when they engage in theoretical reasoning. One of these alien beings is named Natty; Natty is a naturalist. The other alien is Theo. Theo, of course, is a theist. Having already acquired a great deal of information about Earth and its inhabitants, Natty and Theo begin to acquire the data of good and evil. As these data slowly trickle in, Natty and Theo try to predict what they will soon learn about the conscious beings on Earth. I contend that Natty will, at various stages in this process, make more accurate predictions than Theo. One reason for this—the only reason I will emphasize today—is that Theo’s belief in theism undermines certain inferences that naturalism does not undermine.
For example, suppose Natty and Theo already know that many plants die before they ever have a chance to flourish, that many others languish for much or all of their lives, and that even plants that flourish for much of their lives eventually wither and die. Natty and Theo then begin to learn about the animal life on earth. Specifically, they learn that some animals, unlike plants, can be harmed or benefited from their own internal point of view. Before learning more, they consider the question of whether these animals (including of course human beings) suffer the same fate as plants. Do many die young? Do many barely survive, languishing for most or all of their lives? Do some flourish for a time but then decay and die in old age?
Being a naturalist and, like Theo, seeing a plausible connection between these ecological facts about plants and the operation of natural selection, Natty expects to learn that the answers to these questions are all “yes.” Of course, there is an interesting moral difference between plants and conscious animals since the latter, unlike the former, can be harmed from their own internal point of view; and when Natty reasons analogically from facts about plants to the likelihood of similar facts obtaining in the case of animals, she will ask herself whether her inference is undermined by this difference. In other words, she will ask whether this dissimilarity between conscious animals and plants is a relevant one. Because she is a naturalist, however, she will no doubt answer that question negatively. For given naturalism, evolution and nature in general is likely to be blind to moral considerations.
Theo, on the other hand, finds himself with no good reason to believe that these moral dissimilarities are irrelevant; for he believes that the ultimate cause of evolution and of all ecological, botanical, and zoological facts is an omnipotent, omniscient, and omnibenevolent God. Such a God, being omniscient, is well aware that flourishing in the biological sense can benefit some animals, but no plants, from their own internal point of view and languishing can harm them. Being omnipotent, such a being would be as well positioned as possible to ensure that such animals do flourish for at least most if not all of their lives. And being omnibenevolent, such a being would, other moral considerations held equal, want such beings to flourish. So Theo is not entitled to assume that the moral differences between plants and conscious animals are just irrelevant dissimilarities. He would be foolish to predict that conscious animals, like plants, frequently die young or survive but languish for most or all of their lives.
Of course, Theo recognizes that both his knowledge of possible goods and evils and his knowledge of entailment relations between goods and evils are very limited. Thus, he realizes that there might be moral reasons unknown to him for the theistic God he believes in to bring about a biosphere in which many conscious beings fail to flourish and so fail to achieve the good that for which they appear to be designed. He also recognizes, however, that it is also possible and no less likely that his God would have reasons unknown to him not to create a world of that sort. And then there are, of course, the moral reasons for not creating a world of that sort that he actually knows about. So even if Theo is not sure what his God will do, he certainly cannot reasonably judge that the moral differences between plants and conscious animals are irrelevant and so he cannot make use of the analogical inference Natty uses to make her prediction. Therefore, Theo will, if he is wise, not make the same prediction Natty makes. Of course, Natty’s prediction, it turns out, is accurate. So when the data comes in, she will turn to Theo and say: “See. I told you so. Don’t you see now that naturalism is more accurate with respect to these data than theism is?” (emphasis mine)
My heart goes out to all parents of children born with birth defects. But it’s hard to see the flaw in the logic of Draper’s argument, explained above. Everything else held equal, the evidence from birth defects shows that the answer to Christianity Today’s question is, “No. Birth defects are not part of God’s plan because God does not exist.”