The Argument Naturalism Can’t Answer
There’s a problem at the heart of metaphysical naturalism that most defenders never see coming. It’s not about miracles, fine-tuning, or consciousness. It’s more basic than any of that.
Naturalism can’t account for the reasoning used to defend naturalism.
I’ve just released a monograph making this case: The Necessity Argument Against Naturalism (available at Zenodo). The argument is straightforward, but its implications are severe.
The Core Problem
When you prove a theorem, construct an argument, or draw a conclusion from premises, you’re doing deduction. And deduction makes a strong claim: if your premises are true, your conclusion must be true. Not probably. Not usually. Necessarily.
That word “must” is doing real work. Valid inference isn’t just reliable. It’s necessarily truth-preserving. The conclusion cannot fail to follow from the premises. This necessity is what distinguishes deduction from induction, guesswork, or heuristics that happen to work.
Strip away that necessity and deduction loses its distinctive character. It becomes just another pattern that’s held so far, another psychological compulsion we can’t shake, another convention we’ve agreed to follow. None of these can do the work deduction actually does.
So here’s the question: what makes deduction necessarily truth-preserving?
The Collision
Metaphysical naturalism holds that reality is exhaustively constituted by contingent physical facts. Everything that exists could, in principle, have been otherwise. The universe might have had different initial conditions, different constants, different laws. There are no necessary truths about reality itself, only contingent arrangements of matter and energy.
But deduction requires necessary truth. The laws of logic don’t just describe patterns that happen to hold. They constrain what can be the case. The law of non-contradiction doesn’t merely forbid us from believing contradictions. It excludes contradictions from reality. Nothing can both be and not be in the same respect at the same time.
This necessity is ontological. It’s not about how we think or speak. It’s about what can exist.
The collision is direct. Naturalism says all facts supervene on contingent physical facts. But necessary truths don’t supervene on contingent facts. A necessary truth holds regardless of how contingent facts are arranged. It holds in all possible worlds, including worlds with radically different physical configurations.
Naturalism says there are no non-contingent features of being. But logical necessity is a non-contingent feature. The law of non-contradiction doesn’t hold because of how matter happens to be arranged. It holds because contradictions are impossible as such.
The naturalist who argues for naturalism employs valid inference, treats logical connections as binding, and presupposes that conclusions follow necessarily from premises. But on naturalism’s own terms, there is no such necessity. There are only regularities, patterns, contingent arrangements that happen to hold but could have been otherwise.
The Escape Attempts
Naturalists have tried various escapes. The monograph examines them systematically. Each fails.
Laws of nature? These provide only conditional necessity. They tell us what must happen given that these laws hold. But the laws themselves are contingent. Different possible worlds have different laws. Conditional necessity presupposes but does not supply absolute necessity.
Mathematics? If mathematical truths are ontologically real and necessary, then naturalism is false. There would be necessary features of reality that don’t supervene on contingent physical facts. If they’re fictions or conventions, they can’t ground the necessity deduction requires. The naturalist can’t have it both ways.
Counterfactuals and modal talk? These presuppose modality rather than grounding it. To reason about what would have happened under different conditions, you must already employ valid inference. If logical necessity isn’t available, counterfactual reasoning collapses along with everything else.
Dispositions? These are contingent properties of contingent entities. The universe might not have contained things with these dispositions. Even within our world, the connection between disposition and manifestation is contingent. Dispositional necessity explains how entities behave given that they exist. It doesn’t constrain what can exist in the first place.
Brute necessity? This abandons naturalism rather than rescuing it. To posit irreducible necessary constraints on reality is to admit that reality includes necessary features that don’t depend on how physical processes happen to unfold. This is precisely what naturalism denies.
The Self-Refutation
There’s a deeper problem. Any denial of necessary truth undercuts itself.
Consider the claim: “There are no necessary truths.” What’s the modal status of that claim?
If it’s asserted as necessarily true, it refutes itself. The claim says there are no necessary truths, yet the claim itself would be one.
If it’s asserted as contingent, it fails to exclude necessary truths. A contingent denial says only that, as things happen to be, there are no necessary truths. But this leaves open the possibility that there could be necessary truths, or that they exist in other possible situations. The denial doesn’t accomplish what it needs to.
This isn’t a verbal trick. It reflects the structure of assertion itself. To deny something is to exclude it, to say it’s not the case. But exclusion requires that the denial have determinate content, that it rule something out. And ruling something out, if it’s genuine ruling out rather than mere preference, requires that the exclusion hold with necessity.
The necessity-denier is caught in an exhaustive dilemma. Either the denial has the force of necessity, in which case it’s self-refuting, or it doesn’t, in which case it fails to deny.
What This Means
The argument doesn’t establish theism. It doesn’t establish Platonism. It doesn’t construct a positive metaphysics.
What it establishes is that any worldview adequate to rational inquiry must accommodate necessary truth. And metaphysical naturalism, by its own core commitments, cannot do so without ceasing to be naturalism.
The naturalist who continues reasoning, and every naturalist does, must either accept incoherence or revise naturalism beyond recognition. A naturalism that includes necessary truths about reality has already departed from the contingency-only metaphysics that defines the position.
Science survives this argument. Scientific practice is compatible with many metaphysical frameworks. What doesn’t survive is the claim that reality is exhaustively contingent and physical.
The rational enterprise points beyond itself. Reasoning presupposes necessary truths that constrain what can be the case. Logic is not a natural entity like an electron or a field. It’s an ontological constraint on what can exist. The scientist who reasons well engages with an objective structure that transcends the natural order, a structure that makes scientific reasoning possible but is not itself a product of scientific investigation.
The Challenge
The monograph is offered as a challenge. If it fails, it fails at some identifiable point. The naturalist who rejects the conclusion must show where: which premise is false, which inference is invalid, which distinction is confused.
Several responses won’t work:
Dismissing it as religious doesn’t engage the argument. It proceeds from premises about deduction that naturalists themselves accept.
Asserting that science has shown naturalism to be true misses the point. Science employs deduction but doesn’t ground it.
Redefining naturalism to include necessary truths concedes the argument. That’s taking the revision horn of the dilemma.
The argument is logically prior to Plantinga’s Evolutionary Argument Against Naturalism and to the Argument from Reason. Those ask whether naturalism can account for reliable cognition or the causal efficacy of reasons. This asks whether naturalism can make sense of there being necessary truths in the first place. If it can’t, the other questions don’t get off the ground.
Read It Yourself
The full monograph develops these points rigorously across 78 pages. It’s available open-access at Zenodo (DOI: 10.5281/zenodo.18294260). I think I’ve made a case that deserves careful engagement, not casual dismissal.
Necessity is real. It constrains what can be the case. Any worldview adequate to rational inquiry must acknowledge this. Naturalism cannot.
The naturalist who reasons has already conceded what naturalism denies. The only question is whether the concession will be made explicit.
James (JD) Longmire
ORCID: 0009-0009-1383-7698
jdlongmire@outlook.com
Available for discussion and critique.



The piece demonstrates an exceptional level of logical exactness!