Natural Science Include
Department of Philosophy
Huntington, IN 46750
From Perspectives on Science and Christian Faith 45 (March 1993): 57-59.
I am grateful to Alvin Plantinga for his reply to my discussion of his debate
with McMullin and Van Till,
Both Ernan McMullin and I have urged that if Plantinga is going to reject evolution he needs to present his own view about how the variety of living things on the earth, past and present, came about. Plantinga disagrees, and rightly sees this as a major point at issue between us. Unfortunately, however, he devotes most of his space to refuting a view which I have never endorsed and do not hold. I do not believe that, in general, "if you reject a theory or explanation as unlikely on the evidence, you have to be prepared to propose some other theory in its place," with the rider that the replacement theory must be "equal in content" with the theory it replaces. Certainly I may think it improbable, less likely than not, that a given horse will win the Kentucky Derby, without being prepared to say which horse will be the winner.
My own reasoning for saying Plantinga needs to present an alternative is much more specific. In the interest of conciseness, I present it here in the form of an argument with numbered steps:
The modern natural sciences over the past several centuries have proved to be by far the best method we have of learning the truth about the structure, processes, and history of the natural world. (They have been incomparably more successful than the speculations of creationists.)
2.Therefore, one who wishes to learn about these things is well advised to study and carry out research in these sciences.
Once a theory has enjoyed some success and has established itself in some branch of the natural sciences, the normal and appropriate scientific procedure is to continue to accept that theory until it can be replaced by a superior alternative.
Therefore, one who wishes to gain increased knowledge concerning the natural world is well advised to follow the procedure outlined in step 3.
Presumably Plantinga would not agree with this, but it is not clear to me
just which step(s) he would object to. Perhaps he would agree with (3) if
In any case, I do have another reason for insisting that Plantinga needs to specify an alternative, and this reason is drawn from his own procedure. In several places Plantinga makes assertions to the - effect that some piece of putative evidence for evolution is "reasonably probable on the hypothesis of special creation, hence not much by way of evidence against it, hence not much by way of evidence for evolution" (p. 23, and see similar remarks on pp. 24, 104, 105, and 107-8). My question is, "Which hypothesis of special creation is referred to here"? Plantinga replies that "the hypothesis of special creation I had in mind was just the hypothesis that
SC: God created at least some forms of life specially, in a way that did not involve common descent.
Now, the particular piece of evidence referred to on p. 23 is simply the "similarity in biochemistry of all life." And with regard to that particular evidence, I will admit that SC is specific enough to enable us to see that Plantinga's claim is true; it is reasonably probable that God, in specially creating a variety of living creatures, would have endowed them with similar chemistries.
But Plantinga makes similar assertions about other types of evidence, and to
evaluate these assertions we do need a more specific creationist
hypothesis. He says, for instance, that "The fossil record fits versions of
special creation considerably better than it fits TCA" (p. 104), and also
that "the typological structure of the molecular evidence fits very well
with various typological views as to how God might have created some forms of
life specially" (pp. 107-08). Now "the fossil record" and
"the typological structure of the molecular evidence" represent very
broad categories of evidence. And with respect to those categories of evidence,
I submit we cannot evaluate Plantinga's claim without knowing more specifically which
creationist hypothesis he has in mind. The crucial question, of course, is which
of the alleged evolutionary transitions does he accept and which does he reject?
If we are considering the evidence of the hominid fossils, for instance, or the
remarkable genetic similarities between humans and chimpanzees, then it makes a
great deal of difference whether the hypothesis in question accepts the
ape-human transition as valid or rejects it. So as I pointed out before, the
question that cries out for an answer is, at what taxonomic level are the
acts of special creation supposed to have occurred?
What shall we say about theistic science, Plantinga's proposal for a special, distinctively Christian discipline of natural science which incorporates "what we know by faith, by way of revelation, as well as what we know in other ways" (p. 30)? I think it needs to be emphasized that our disagreements about theistic science are less extensive than they might appear. To begin with, I wish to limit my comments here to the natural sciences; the sciences of human behavior raise different issues which require separate treatment. My disagreement, furthermore, is specifically with the proposal for a natural science which includes content derived from faith and revelation. But I would strongly encourage Christians in the sciences to reflect critically about their scientific work in the light of their Christian faith, and to endeavor to arrive at a comprehensive world view, integrating their scientific understandings with their faith perspective (see my comments on p. 159). Now this task, also, would be included by Plantinga under the heading of "theistic science," and with regard to that part of his program we have no disagreement whatever. I mean to focus, then, on the idea that natural science should include content derived from revelation. About this, three points need to be made. To begin with, if we understand "theistic science" in this restricted sense, Plantinga's claims about the dangers of rejecting it are unwarranted. He says such rejection carries with it the dangers of "failing to discern the patterns and currents of spiritual and intellectual allegiances of contemporary culture, intellectual compartmentalization, failing to lead all of life captive to Christ, [and] being conformed to this world." I agree that, were Christians in the sciences simply to ignore issues of integration between faith and science, the dangers Plantinga cites would threaten. But I do not think these dangers are especially pressing if these scientists follow the suggestion to intensively pursue issues of faith and science, but without incorporating content from revelation into their scientific theories.
My second point is this: When we are working with the restricted conception
of theistic science, it becomes apparent that TCA is not merely a handy
illustration, but is rather the point on which the whole debate hinges. The
reason for this is that the question of evolution vs. special creation is really
the only substantial point concerning which it is still claimed that revelation
provides knowledge which natural science must incorporate. It wasn't always this
way, of course. We all know the sad story of Galileo and the Church; since then,
astronomy has generally been left to the astronomers.
My third point is simply to point out that Plantinga has made no case for
saying that Scripture does teach special creation. To be sure, he thinks
it likely that God "intends to teach us that human beings were
created in a special way and by an act of special creation" (p. 82) (though
he doesn't believe that God intends to teach us this!
But things are even worse than this. In my discussion I said that Plantinga
should find "devastating" the view of James Barr according to which
the author(s) of Genesis intended to teach a literal six day creation, a young
age for the earth and mankind, and a universal flood. In reply Plantinga reminds
us of his view (which he shares with Calvin and Aquinas) that God is the
ultimate author of Scripture, and that what matters is what he (and not the
human authors) intends to teach us through it. Quite so, and I, also, am happy
to say that what ultimately matters is what God is teaching us in the Bible.7
I conclude, then, that there is no credible case for the view that Christians should attempt to construct a "theistic natural science" which includes content derived from revelation. But there are other aspects of Plantinga's proposal for "theistic science" which are admirable and deserve to be pursued vigorously.