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Richard Dawkins visits our campus today and will give a lecture entitled "The Magic of Reality". In preparation for his visit, I finally got around to reading his book The God Delusion, and have been thinking about some of Dawkins' points related to "God of the gaps" arguments.
The main criticism of such arguments goes like this:
When there is a gap in our scientific understanding, it is wrong and misguided to appeal to God/supernatural explanations. The history of science shows us that theology always loses, because science ultimately comes up with a naturalistic explanation. The gaps are narrowing, and all is ultimately explainable by science.
Several responses can be given to this criticism, although it should be noted at the outset that people have made inappropriate appeals to God as an explanation for gaps in our scientific knowledge, so that to an extent the criticism should be heeded. However, there are some replies that a theist can give:
1. We don't limit theological explanations to gaps in scientific knowledge.
There are theological explanations with respect to questions that are not under the purview of science. Questions of meaning and value, for example, cannot be completely decided by science as such. These are philosophical questions, as well as religious ones, but they are not strictly scientific.
2. We can debate whether or not theology always loses to science.
The warfare metaphor between science and religion is too simplistic, but even so there are cases of conflict where theology has won. Against the science of their day, theologians have rightly predicted: that the universe is temporally finite; that a behaviorist account of human beings would be unsuccessful; and that anthropologists would discover a widespread belief in some sort of Supreme Being.
In addition, it is not clear that the conflict is as deep or widespread as one might be led to believe. As Harvard biologist Stephen Jay Gould put it, "Either half my colleagues are enormously stupid, or else the science of Darwinism is fully compatible with conventional religious beliefs—and equally compatible with atheism" (Scientific American, 1992).
3. We should expect there to be only a very few gaps in scientific explanations.
Even if most alleged gaps are not genuine gaps, it does not follow that all of them are. Moreover, on Christian theism at least, the view is that God usually operates through secondary causes, that is, through the laws of nature. Finally, the value of a miracle or gap as evidence for God's existence only arises in a context where such occurrences are comparatively rare! So it is consistent with theism that there be few gaps.
4. A God of the gaps style critique of science.
Most scientific theories of the past have been replaced or falsified, and this might imply that much of our current science will suffer the same fate. Of course, the same applies to inappropriate appeals to God as an explanation. The important point here is that one could make an inductive inference that given the history of science, we should expect a high failure rate related to many current scientific theories.
In sum, arguments for and against theism based on God of the gaps style arguments are interesting and this can be a useful discussion to have, but people in both camps often approach it in too simplistic a manner and draw conclusions that are not warranted by the evidence.
See Scaling the Secular City for more on the above points.
