Here I respond to Keith Parsons’ second post. Jeff Lowder is keeping track of the existing and forthcoming installments in my exchange with Prof. Parsons here.
Keith, thanks for these remarks. The question we are now considering is: Why would the material universe or anything in it (an electron or a quark, say) require a cause to conserve it in existence? Your view is that the supposition that it requires one is “gratuitous.” You write: “Is there anything missing from an electron that would have to be filled in or supplied from outside? There is nothing in our physical theories that indicates such a lack.”
Now, this assumes that physical theory gives us an exhaustive description of electrons, quarks, and material reality in general, or at least something near enough to an exhaustive description for present purposes. For only if we make that assumption would the absence from physical theory of a reference to the need for a conserving cause give us any reason to think a material thing doesn’t require one. (Compare: The absence of legs from the Mona Lisa would give us reason to believe that the woman it pictures was legless only if we supposed that the portrait captures everything about her that there was to capture -- which, of course, is not the case.)
Now I would say that there is no reason whatsoever to make the assumption in question vis-à-vis physical theory, and in fact decisive reason to reject it. Nor does one have to be a Scholastic or a theist to agree with me. Bertrand Russell, for one, agreed at least about that much. As he wrote:
It is not always realised how exceedingly abstract is the information that theoretical physics has to give. It lays down certain fundamental equations which enable it to deal with the logical structure of events, while leaving it completely unknown what is the intrinsic character of the events that have the structure… All that physics gives us is certain equations giving abstract properties of their changes. But as to what it is that changes, and what it changes from and to—as to this, physics is silent. (My Philosophical Development, p. 13)
Now if physics gives us only the mathematical structure of material reality, then not only does it not tell us everything there is to know about material reality, but it implies that there must be more to material reality than what it tells us. For there can be no such thing as structure by itself; there must be something which has the structure.
Nor, even if we could make sense of the idea of structure existing by itself, would physics give us any reason to believe that that is all there is. To be sure, if there are features of physical reality susceptible of the mathematical description to which physics limits itself (which, as the success of physics shows, there surely are) then physics has a good shot at capturing them. But if there are features of reality that cannot be captured by those methods, physics is guaranteed not to capture them. So, that physical theory doesn’t tell us such-and-such really doesn’t mean much where metaphysics is concerned, because its very methods guarantee that it will not capture certain aspects of reality even if they are there.
Nor, contrary to a common fallacy, does the predictive success of physics’ methods give us any reason whatsoever to believe that there are unlikely to be features of reality that cannot be captured by its methods. As I have said elsewhere, to assume this is like assuming that the success of metal detectors shows that there are unlikely to be features of reality that cannot be captured using metal detectors; or it is like the drunk’s argument that his lost car keys are unlikely to be anywhere else but under the lamppost, since, after all, that is where the light is and where he has already found his lost wallet and sunglasses.
So, physics is of its very nature incomplete. It requires interpretation within a larger metaphysical framework, and absolutely every appeal to “what physics tells us” presupposes such a metaphysical framework, implicitly if not explicitly. This is as true of the appeals made by naturalists and atheists as it is true of the views of Scholastics. So, physical theory is simply not going to settle issues like the one in question. The issue is metaphysical and can in principle only be settled via metaphysical argumentation.
Now, the Aristotelian-Scholastic tradition, for metaphysical reasons that have nothing essentially to do with natural theology, maintains that any possible material reality will have to have an actuality/potentiality structure. The reasons have to do with the very preconditions of affirming, contra Parmenidean arguments, the reality of change and of multiplicity. Neither change nor multiplicity, the Scholastic argues, can coherently be denied; and neither can be made sense of unless between actuality and nothingness there is a middle ground of potency or potentiality. Now, when the actuality/potentiality distinction is worked out, it implies that every finite substance is a compound of essenceand existence (with essence being a kind of potentiality and existence a kind of actuality) and that every material substance in particular is a compound of substantial form and prime matter (with substantial form corresponding to actuality and prime matter to potentiality).
Obviously not every reader will agree with or even be familiar with these ideas. But there are serious arguments for them, arguments which I have defended at length and against all the standard objections in my book Scholastic Metaphysics: A Contemporary Introduction. And when their implications are worked out, it turns out that nothing composite in these ways can exist on its own even for an instant. For instance, prime matter is pure potentiality for the taking on of form, and qua pure potentiality has no actuality of its own. In mind-independent reality, then, it can exist only as informed by a substantial form. The substantial form of a purely material thing, though, is, apart from matter, a mere abstraction. In mind-independent reality, then, it can exist only as instantiated in prime matter. But this leaves us with a vicious metaphysical circle unless there is something outside the composite that accounts for the parts being combined. And the regress this threatens to generate can in principle be terminated only by that which is in no way a composite of actuality and potentiality -- something which is pure actuality devoid of potentiality.
This is compressed, obviously, and much more could be said both in the way of working out the background metaphysics (as I have done in the book just referred to) and in the way of spelling out the arguments for the necessity of a sustaining cause and defending them against objections (as I have done in my American Catholic Philosophical Quarterlyarticle “Existential Inertia and the Five Ways”). But this much suffices to show that there is nothing gratuitous about the idea of the need for a conserving cause. It has a serious metaphysical motivation, and a motivation that is independent of natural theology, even if it ultimately has implications for natural theology.