Here's the thing: much depends on what you mean by "natural theology." If we mean by this, "theology that proceeds to the knowledge of God without the mediation of religion," we have a problem. How, indeed, would theology proceed naturally to the knowledge of a being revealed in contradistinction to the world of nature? And yet if we mean something else by the term "natural theology," there are ways of accepting the venture as a faithful one. So let us consider what natural theology is.
Perhaps the easiest spot to begin is with the Gifford Lecture folks at St. Andrews, the holders of one of the most esteemed trusts in the field of natural theology. Lord Gifford's bequest establishes these lectures on the following premise:
"I having been for many years deeply and firmly convinced that the true knowledge of God -- that is, of the Being, Nature, and Attributes of the Infinite, of the All, of the First and the Only Cause -- that is, the One and Only Substance and Being -- and the true and felt knowledge (not mere nominal knowledge) of the relations of man and of the universe to Him, and of the true foundations of all ethics and morals; being, I say, convinced that this knowledge, when really felt and acted on, is the means of man's highest well-being, and the security of his upward progress, I have resolved, from the 'residue' of my estate as aforesaid, to institute and found, in connection, if possible, with the Scottish Universities, lectureships or classes for the promotion of the study of said subjects, and for the teaching and diffusion of sound views regarding them among the whole population of Scotland."A good and a faithful Scot. And perhaps there's something about the Scots, for the ways that Torrance was able to do justice to both Barth and the intersections of science and theology. So what do we have here? The promotion, teaching and diffusion of sound views about the being, nature, and attributes of God, the relationship between the creation and God, and the basis for moral activity in the world, because it's good for us to know this stuff. Thoroughly combined, of course, with the standard speculative metaphysics and progressivist ideology of the day. And as he goes on, it becomes clear that this description -- along with "all Obligations and Duties thence arising" -- constitutes "'Natural Theology,' in the widest sense of that term." Now, so far this is very congenial, or can at least be made so -- and then we come to Lord Gifford's fifth stipulation governing the lectures:
I wish the lecturers to treat their subject as a strictly natural science, the greatest of all possible sciences, indeed, in one sense, the only science, that of Infinite Being, without reference to or reliance upon any supposed special exceptional or so-called miraculous revelation. I wish it considered just as astronomy or chemistry is.I think most of us today, except to the extent that we consider theology one of the Geisteswissenschaften, or human sciences, do think of ourselves as doing some sort of naturwissenschaftliche Theologie. Science has, by now, won the methodological day. (We are, after all, moderns.) We wrestle with a history of speculative idealism while groping toward empirically rational, systematically interconnected understandings. Even our philosophy leans this way. Instead of working toward the ideally rational, we now tend to work toward the real under the rational, or at least toward improved contextual rationalizations of the real. But there's empirical epistemology, and then there's natural theology.
So: observe the stipulation, in the ways it modifies the original premise. What Lord Gifford is advocating is, in the high Medieval sense, theology as the queen of the sciences -- except that it has become the science of "infinite being," which would seem to rely on some (however impoverished) form of analogia entis. But you can see the underlying idea: theology as a science that, in the wisdom of the 1880s, could stand on the basis of observable evidence without relying on some form of special pleading, and speak convincingly and rationally of God. And I can see why this would be a necessity -- as an apologetic move. Special revelation is by definition not generally available. The exceptional and miraculous constitute categories of violation of the general order.
And why should we complain about this? These are exactly the sorts of "proofs" we rule out as Christians faced with any of various "secret" or gnostic positions. We reject the claim that, without this or that closely held secret knowledge, the truth cannot be known. Inevitably these are claims to witnesses that will not stand for examination. And so Gifford defines this broadest sense of natural theology -- even if in narrower senses it may cease to be a defense of the faith of the Kirk -- such that anyone may speak of the knowledge of God, from any relevant background or none at all, and everyone may be taught of the knowledge of God. The knowledge of God cannot, therefore, be built on counterfactuals or non-examinable claims and retain the respect it is due. And so we have Lord Gifford as a defensor fidei.
And yet how often, in narrower instances of natural theology, are we dealing with the presupposed faith of the Kirk? Certainly not always, though the Gifford Lectures have provided notable exceptions. I think Barth may have in fact done the best service to Lord Gifford in proceeding from Knox's Scots Confession! We are not, in fact, called here to prove the faith to be true, but rather to teach it because it is true. And Lord Gifford calls us to do so under strict, realistic, empirical, and generally available epistemology. Of course, he does so in the terms of his day, but so must we -- in the terms of ours.
And so it is certainly true that natural theology follows theology (properly so-called), just as Calvin asserts and Barth amplifies: we may know of God in and from creation, provided that we have first come to know God by God's self-revelation. Which means that we may do theology from nature -- as long as we realize that it is apologetics, and have done our dogmatics in proper scientific fashion from the object of our science Itself. But this knocks the notional distinction between revealed and natural theology, at least in its Modern connotations, on its side. The question was never whether we worked from evidence -- the question was about the quality of our evidence.
So let us understand dogmatics, as we have come to understand it since the Enlightenment, as a science proceeding on the basis of evidence appropriate to its Object. As such a science that proceeds from the evidentiary witness of those who participate in the long history of the actions of our faithful Object. On empirical grounds we must, therefore, come to know God as God has given Godself to be known, phenomenologically. As we have historically known God because of this self-revealing action, likewise, and therefore as God comes to us anew through our faithful study of this witness. And so, even in this threefold sense of the Word of God, this is a witness that continues to stand for examination. It stands generally available for questioning, even though some among us continue to try to "protect" it from inquiry and unfamiliar opinions! And it remains this because the witness of scripture is a public and historic text, and as such stands in a history of rich context, with a long tradition of analysis and interpretation that precedes any work we may do.
And, as we must, the text presupposes the reality of the faith and its Object. It does not see fit to argue the faith, except as persuasion for this faith and not some other -- this God and not some other. As with any witness, the witness of scripture has seen and heard and experienced, and therefore has no need to question that it has seen and heard and experienced, even as it works to understand what it has seen and heard and experienced, and what that means for life in the world. This witness is, in fact, the demonstration of the effects of the existence and action of God, which together form the basis for the faith of the people. It is this in story, in narrative whether as interpretation of historical events or of present knowledge. And so the nature of theology as a path toward understanding follows the nature of our available metaphysical ground, even if it moves from there into novel epistemological systems -- which it constantly and inevitably does, because even the Fathers did not live in the world of the authors.
If natural theology does not follow from the presupposition of the faith of the church, if it proceeds to operate against the dogmatic necessities of the ground of the faith -- then what is it? It certainly ceases to be good science with respect to this Object. As Barth has said, it is derivative, a shadow of the religion from which it departs. Philosophical theism routinely is this, by way of developing a concept of God as God may primarily be known from nature. Deriving a natural genus for a species of one. Hacking off anything that smacks of special pleading for an object that couldn't otherwise be claimed to exist. A deity wholly within and of the created nature of the ordered world, if not by belonging to the world, then by being the origin and maintainer of the created order. Or, by speculative abstraction, a deity whose actions (centrally the creation of the world) define the necessities of its existence. And thence, by a combination of positive and negative theology, to a deity whose existence is dictated by what we conceive of as the necessities of the action, but who is not in any way as we are or would perform them. And yet this, too -- Pseudo-Dionysius' via triplex -- has no business being used without the presupposition of the faith! Once it stops working from the grounding witnesses of the faith to reach its Object, even if only partially, it works blindfolded and with its hands bound. It works from the Cartesian cogito -- as though Descartes did not proceed to the second thing he could know, and from there to the physics of the world.
It seems to me that a major root of the problem, here, is our embarrassment of scripture -- and the main root of that problem is the vigorous protests of orthodoxy in the attempt to protect scripture from general philological and critical access. This is the fight underlying the discussion of natural theology as opposed to revealed theology. It's a problem, we might think, to have a canon of scripture that doesn't consistently support the dogmatic theology of our historical interpretations of it. And yet is that the problem? That the state of our knowledge changes the ways we inquire of scripture, and therefore the results we derive from our inquiries? Isn't all reality, all evidentiary data, like this? The data is real, within the error constraints of the measurements and the intent of the recorder -- and all the conclusions are provisional. Embarrassment of this reality is the root of natural theologies that take their stands against the self-revelation of God as witnessed in scripture -- as though it were special pleading. And why? Because of a classically Protestant orthodox refusal to permit the general inquiry of scripture, except by the initiate, combined with a high ideological threshold for initiation. I can't get around this, though a second is like it: the insistence upon the propositional constancy of doctrine. Upon these two hang all religious withdrawals from dialogue with scientific methods. Upon these two hang the modern scientific withdrawals from dialogue with theological methods. And so I blame us: we have created the necessity for "natural theology" as it appears today. A theology performed by those for whom the presuppositions of the faith are undesirable -- because its propositions are untenable. And it derives from the same rift that appears at the root of the divide in the modern academy between Biblical and theological disciplines. We hold too tightly to what we believe is right about God and the world -- to our provisional claims as though they were the data set itself. And those who break from this mania, do so piecemeal and form communities outside of the walls according to their common intentions. And some will always break off earlier or later than others, depending on when the artificial restrictions become untenable for them.
And yet it need not be this way. Connected to the ground of faith, and to the faith itself, observation of the world is the ground for the most basic of natural theologies: the doctrine of creation. Because when we know this God, who has acted for us, and we observe the world around us, we know two things: that God is Lord of the world, and that the world is not entirely as it should be. From here, many routes are possible -- though it is important not to mistake our dissatisfactions with the world as we see it, for the ways that the world does not perfectly behave as creation before its creator. As interpreters we are most certainly deeply stuck within the problem. And this is why, at heart, most theologies and stories of creation are deeply bound to theodicy. One might, indeed, suggest that the response of "natural theology" as it proceeds without the faith is to refuse to vindicate God in its creation story. But we need not vindicate God over the world, or the world over God, in order to justify both as they are!