As Hume pointed out, there is no process by which past events confer existence on future ones, nor do we observe any form of “natural” necessitation. Moreover, scientific laws — classical ones, at least — do not even purport to describe such a process. In fact, they are not even diachronic: they describe simultaneous interactions in which dynamic properties such as energy and momentum, which the laws treat as conserved rather than created, are transferred from one entity to another. Assuming the world continues to exist, future events will then emerge naturally and predictably from those that went before. But they will not be produced by them. In that respect, the idea of natural causation is on the same footing as agent causation: neither is a process in its own right, and neither guarantees the existence of an thing. It turns out, then, that free exercises of the will differ from the rest of the world only in being nomically discontinuous with it. The problem of their provenance of a piece with that of the provenance of things in general.
Even if the empirical world were deterministic through and through — which the evidence indicates it is not — nomic causation cannot explain why we have this world rather than some other, or no world at all.
Why does the Universe exist? There are two questions here. First, why is there a Universe at all? It might have been true that nothing ever existed: no living beings, no stars, no atoms, not even space or time. When we think about this possibility, it can seem astonishing that anything exists. Second, why does this Universe exist? Things might have been, in countless ways, different. So why is the Universe as it is?
Why anything? Why this?
In the 1948 Copleston-Russell Radio Debate, the question of whether or not the universe’s existence was brute seemed to turn on a possible fallacy of composition, in other words, whether or not the whole begged further questions, transcendently, or could be understood merely in terms of its parts, phenomenally.
All of this seems to beg Heidegger’s question: Why not rather nothing?
And this all seems to invoke Wittgenstein’s musing: The mystical is not how the world is, but that it is.
And it brings us back to McCann and Parfit’s recognition that, even if we accepted the existence of the universe as brute (or refused to predicate existence of being), questions would not cease begging.
Heidegger would, instead, ask: “Why not rather something else?”
Wittgenstein would instead muse: “The mystical is not that the world is, but why this world is.”
In either case, whether the question begging remains “Why anything?” and/or “Why this?” …
McCann’s observation would still obtain in that “free exercises of the will differ from the rest of the world only in being nomically discontinuous with it” …
And McCann’s insistence would still apply regarding both natural causations and non-nomic exercises of the human will insofar as the “problem of their provenance [would remain] of a piece with that of the provenance of things in general” …
For the provenance of things in general would merely transmute from a question of Why anything? to one of Why this? …
And the question would become Why this nomicity?
And our Peircean argument would yet infer the Ens Necessarium, if not in terms of being, then, in terms of doing.