Ed, Here is your fourth question to me:

“4. In response to another reader’s question, about Craig’s version of the First Cause argument, you wrote: “Both theists and atheists begin with an uncaused brute fact. For Craig it is God, and for me it is the universe.” Now, as you know, the expression “brute fact” is typically used in philosophy to convey the idea of something which is unintelligible or without explanation. And your statement gives the impression that all theists, or at least most of them, regard God as a “brute fact” in this sense.

But in fact that is the reverse of the truth. Aristotelians, Neoplatonists, Thomists, Leibnizian rationalists, et al. would denythat God is a “brute fact.” They would say that the explanation for God’s existence lies in the divine nature — for Aristotelians, in God’s pure actuality; for Neoplatonists, in his absolute simplicity; for Thomists, in the fact that his essence and existence are identical; for Leibnizians in his being his own sufficient reason; and so forth. (Naturally the atheist will not think the arguments of these thinkers are convincing. But to say that they are not convincing is not the same thing as showing that the theist is either explicitly or implicitly committed to the notion that God is a “brute fact.”)

But perhaps you think the standard interpretation of the views of Aristotelians, Neoplatonists, Thomists, Leibnizian rationalists, et al. is mistaken. Perhaps you think that these thinkers are in fact all explicitly or at least implicitly committed to the thesis that God is a “brute fact.” So, could you please tell us where you have spelled out an argument justifying the claim that all or at least most philosophical theists regard God as a “brute fact” or are at least implicitly committed to the claim that he is? Is there a book or journal article written by you or by someone else in which we can find this justification?”

The short answer is that my statement was not meant as a historical remark, but as an assessment of what I see as the genuine philosophical alternatives. As I see it, the choice between naturalism and theism comes down to a choice between ultimate brute facts: God or the universe. Which is the more satisfactory terminus of or explanatory chains, the primordial or fundamental features of the universe, on the one hand, or a supernatural being with the omni-predicates attributed by theism? My view is that the former choice is at least as defensible as the latter, and that each choice amounts to the selection of a brutally-factual end-point for our explanatory enterprises.

As for your historical analysis, you are, of course, exactly right. Traditionally, most theists have regarded God as in some sense self-explanatory. Recently, perhaps in response to accumulated skeptical responses to traditional metaphysics, some leading theists seem to be backing away from those claims. My reading of Richard Swinburne is that he concedes that the universe could be the ultimate, uncaused existent, but that theism is the preferred hypothesis because of its allegedly greater simplicity (an argument I challenge in detail in my 1989 book God and the Burden of Proof). Likewise, as I understand William Lane Craig, his argument does not rest on the Principle of Sufficient reason, or any definition of divine necessity, but upon the metaphysical intuition that whatever begins to exist must have a cause. When it comes to things that begin in space and time, I share Craig’s intuition. When it comes to the origin of space/time itself, I do not.

Why think that there could be brute facts? Two reasons: (1) Our ordinary explanatory practices definitely do not require total explanation, and (2) The alternative to brute facts—that anything could be self-explanatory—is highly dubious.

(1) In all of the modes of explanation in natural science and ordinary life, explanation proceeds piecemeal from explanandum to explanans, where the latter, at least temporarily, is left unexplained. There is nothing wrong with this procedure. I can know that the pipes burst because of the freezing temperatures and the fact that ice is less dense than water, even if I do not have detailed knowledge of the structure of the water molecule. In tracing back causes to effects we hope ultimately to come to some set of completely general and basic laws and some set of fundamental entities. Let’s suppose that the Holy Grail of physics is found and a satisfactory TOE is one day established. We will then have some set of ultimate facts for which no deeper explanation exists, and this is precisely what we have hoped all along to find. In explanation, something is always left unexplained, and that this is the case when we reach physical “rock bottom” should neither surprise nor chagrin us. Indeed, there are logically only two alternatives to reaching a brutally-factual explanatory “rock bottom”: Either the explanatory chain proceeds back ad infinitum, or it terminates in something that is not brutally factual but is, in some sense, self-explanatory. As for the first alternative (and pace Prof. Craig), we cannot know a priori that the chain does not extend forever. I am supposing that, in fact, it seems to terminate in a fundamental theory. The second alternative to a brutally-factual explanatory terminus is something that is self-explanatory.

(2) What could it possibly mean to say that something is self-explanatory? I know that, as you note above, Ed, many philosophers have made suggestions here. I find these to be very obscure. They sound to me like verbal formulas devised to obviate a problem rather than solve it. I am not even sure that it is coherent to say that “God is pure actuality” or “God is his own sufficient reason.” I would have to ask for a very careful unpacking of these phrases before I would concede that they are meaningful.

In the meantime, it seems to me that the most obvious way for something to be self-explanatory would be for its existence to be logically necessary. But this option leads us into all the notorious problems associated with the ontological argument. How can there be a concept that guarantees its own instantiation? It can never be contradictory to deny the exemplification of a concept, because that denial does not contradict any of the content of that concept, but only denies that such content is instantiated in extra-conceptual reality. “The non-existent necessarily existent being,” is, of course, a contradictory concept. However, there is, and can be, no contradiction in saying “The concept of the necessarily existent being is not instantiated.” In fact, as has long been known since Russell’s famous example of “the present King of France,” to deny that concept is exemplified is merely to say “There is no x such that x exemplifies predicates P1, P2, P3…Pn.” Such a statement in no way contradicts the mentioned concept, whatever its content.

In what other way, other than by being logically necessary, could an entity be self-explanatory? Well, it could be metaphysically rather than logically necessary. As far as I know, the best candidate for specifying a notion of metaphysical necessity is the PSR, which we may express as: “Nothing exists or is what it is unless there is a sufficient reason for its existence and its nature.” But why should we accept the PSR? As I say above, our ordinary explanatory practices do not presuppose it. Is it intuitively obvious, as I think that Leibniz held that it was? Not to me. On the contrary, with Hume, my intuition is that there very well could be something that exists without any explanation. As curious creatures we may hanker for an explanation for, literally, everything, but I can see no a priori basis for thinking that reality owes us such satisfaction.

The upshot is that if there are no indisputable principles requiring either a logically or metaphysically necessary being, then it is eminently rational to posit brute facts.

Ed, thanks for the chance to address these questions. As always, the subsequent discussion could go on forever, but life is short, and you and I both have many other pressing duties.