How to Block Arguments for God with Aristotle

... and Then Open Them Back Up Again

Aristotelianism can complicate many theistic arguments. Why? Because Aristotelians are real essentialists, and real essentialists can make legitimate, non-contrived appeals to necessity. Take the fine-tuning argument: when someone asks why the mass of the electron is precisely 9.11 x 10⁻²⁸ grams, an Aristotelian might appeal to the electron’s nature—its mass is necessarily what it is because of the essence of the electron.¹ In other words, if the laws of nature are simply the laws of the natures of things², and if the natures of things are fixed and could not be otherwise, one can see how the fine-tuning argument might lose some force.³

Now consider the moral argument. For an Aristotelian, moral norms are dictated by human nature, which couldn’t have been otherwise. In my view, the best way to sidestep (at least the more popular) moral arguments for God is by adopting Aristotelianism, which grounds a broad virtue ethic and natural law, making certain moral truths necessary. (For those who’ve read my book—in other words, the A students—you’ll recall I make this point rather strongly and suggest that a proper [that is, non-sucky] moral argument really just feeds into an act-potency cosmological argument from an Aristotelian perspective.)

A similar Aristotelian story could also take some wind out of the sails of the psychophysical harmony argument. (Psychophysical harmony is the congruence between physical processes and conscious experience. Aristotelian essentialism, with its commitment to form and matter as integrated, could offer a natural way to explain mind-body harmony among the relevant entities—in other words, no need for divine tinkering.)

So, is this all bad news for theism? Well, I should hope not, given that I’m quite a committed Aristotelian and a theist.

First, Aristotelianism fits poorly within naturalism—which is why most naturalists are not Aristotelians. As Lloyd Gerson has pointed out, Aristotelianism is part of Big Tent Platonism and is largely defined by what it opposes: nominalism, reductionism, mechanism, skepticism, atomism, etc.—in other words, naturalism.⁴ It becomes extremely contrived, to say the least, for a naturalist to start picking up Aristotelian commitments, especially given that a large part of what drives naturalism is a commitment to a broad scientism. Science, as we know, doesn’t have much to say about Aristotelian forms (though the Aristotelian would argue these are necessary background commitments for the intelligible practice of science itself).

Second, the metaphysical picture in Aristotelianism naturally leads to theism in various ways. Aristotle himself thought that all hetero-explicable matter-form composites ultimately required the simple, purely actual prime mover, which is auto-explicable.⁵ Moreover, Aristotelianism is committed to the act-potency distinction—a necessary concept for making sense of change, composition, and other undeniable aspects of reality—and this act-potency distinction opens up many traditional cosmological arguments for God (some of which I explore in my book). Finally, as I argue in my forthcoming paper on The Millerian Cosmological Argument, constituent ontology (which Aristotelianism embraces) seems inherently unstable unless there is some absolutely simple first principle behind it all—namely, God. In fact, I would say Aristotelian metaphysics ultimately necessitates theism. 

Lastly, assuming it’s not necessary for any particular form or essence to be instantiated—which seems obvious, given their inherent contingency from the simple fact that many of the same forms exist at different times, for different durations, and in different places—we need an account of why just the forms that exist actually exist, and why they’re organized as they are. This brings us to what is effectively a “fine-tuning of forms” argument, where it seems that just the right arrangement (and perhaps number) of forms are at play to produce an ensemble that’s remarkably orderly and stable.⁶ Surely, even for the Aristotelian, this need not have been the case, and to suggest otherwise would be (if I may say so) laughably contrived.

As it happens, it’s largely because I find Big Tent Platonism so theoretically fruitful that I’m not just a theist but a classical theist. That said, if I were a naturalist looking to counter arguments for God that some non-classical theists consider quite strong—like fine-tuning or psychophysical harmony—I’d lean toward an Aristotelian approach, as it provides a principled basis for a necessity objection. Ultimately, I don’t think this strategy works, because I don’t believe one can consistently be both an Aristotelian and a naturalist, but I think it’s the best—or at least an interesting—move.

1. This isn’t to say its mass couldn’t be a contingent property, only that, for all we know, it could be essential from an Aristotelian perspective—which is enough to raise the objection.

2. For a defense, see Real Essentialism.

3. However, not all constants are so easily tied to physical entities. For instance, the cosmological constant, which affects the universe’s rate of expansion, doesn’t have an obvious link to the nature of any single physical thing. But this may just reflect our current ignorance; after all, there are plausible theories (or so I’m told) about a hypothetical “quintessence field” that pervades space and exerts a repulsive force—possibly a real physical entity whose nature might help explain the cosmological constant. How plausible is this? I have no idea, but it at least shows that the Aristotelian has some options for driving the necessity objection all the way home.

4. See Platonism and Naturalism.

5. Gerson also makes a big point of this. See especially From Plato to Platonism.

6. So, for example, while the electron may have to have the mass that it does, perhaps there could have been another entity—the "schmectron"—with a different mass, which could just as easily have been instantiated instead of electrons. If that were the case, our universe might lack the sort of harmony or stability it currently enjoys