This is an idea which, although I believe it strongly, I do not yet want to bother to write a properly good essay explaining it, especially since it’s really not rocket appliances and ChatGPT can explain it pretty damn decently. If you are interested in this idea, you may be interested in some of the points made in David Lewis’s paper “Noneism or Allism” (PDF). I believe even after one convention is adopted and theism is accepted within it, fuller explanations are in order about how theism works (and whether all the usual predicates applied to God, also known as divine attributes, can be recovered), and no such explanations are attempted here because, for now, I just wanted to get the point registered somewhere about existence in general and how a convention must be explicitly stated and defended when arguing about it.
Existence, by Convention: Why “God Exists” Is Sometimes True
Philosophers disagree about almost everything, but the word exists might be the most overworked and understudied term in the quarrel. We use it to talk about chairs and quarks, numbers and novels, legal persons and possible worlds—and God. Yet we rarely say what rules we’re playing by when we deploy it. The result is cross-talk: one side proves that X exists while the other proves that X doesn’t, and both are right because they’re keeping score with different rulebooks.
This essay develops a simple thesis: claims about existence in general—and theism in particular—depend on a linguistic convention governing what we count as existing. Different conventions make different existence-claims come out true or false. Philosophers should therefore state and defend their convention up front. Doing so doesn’t trivialize metaphysics; it clarifies it.
What a “convention of existence” is
A convention here isn’t a mere whim. It’s a norm that fixes the inferential role of “exists”: what follows from existence talk, what justifies asserting it, and what counts as evidence against it. Think of it as choosing a measurement system. Inches and centimeters are not “the same” as such, but once a system is fixed, precise statements and comparisons become possible. Likewise, once an existence convention is fixed, we can say which sentences come out true, what data are admissible, and which inferences are licensed.
Four prominent conventions structure much contemporary debate:
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Deflationary (Thomasson-style): To exist is to be among the things our accepted terms and practices commit us to. If a community’s language and norms permit talk of electrons, novels, or committees, then—barring special reasons to retract—their existence is unproblematic.
God? Sometimes. If “God” is part of a community’s legitimate referential toolkit, then “God exists” is true within that practice.
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Neo-Quinean: To exist is to be the value of a bound variable in our best theories. We quantify over what our most explanatorily successful, predictively powerful theories require.
God? Only if required by a best theory. That could be a moral theory (divine command, ideal observer), or—in more controversial cases—a biological or cosmological theory (intelligent design, creationism). If no such theory survives competition, “God exists” is false or at least unlicensed.
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Empiricist: To exist is to be (actual or possible) object of sense experience. The admissible evidence is perceptual.
God? No. By definition, the theistic God isn’t an object of sense experience. At best, believers report experiences as of God; but the convention excludes theoretical posits that never show up sensibly.
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Platonist: To exist is to be the object of a concept. Numbers, properties, forms—and any adequately grasped idea—exist in a mind- or language-independent way.
God? Yes. If the concept of a perfect being is coherent, there is such an object.
Each convention has its own standards of evidence, scope, and default burdens of proof. None is linguistically mandatory. Each is a disciplined way to speak.
How theism shifts with the convention
Consider how “God exists” behaves under each rulebook.
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Deflationary: The question reduces to eligibility within a practice. In a liturgical or devotional discourse where “God” plays a stable referential role tied to public criteria (texts, rituals, authorities), “God exists” can be as straightforward as “committees exist” in administrative discourse. The assertion is licensed unless the practice is undermined (say, by showing its terms are empty or incoherent). This makes theism locally true in some language games, without global metaphysical inflation.
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Neo-Quinean: Theists must show that postulating God yields superior theories—of value, meaning, or the universe—once simplicity, predictive success, and unification are weighed. Here “moral theism” (God grounds normativity) is a cleaner target than “scientific theism” (God explains biological or cosmological data), because value theory is already permissive of non-empirical posits. If some version of divine command or perfect being theory best explains moral facts, then quantifiers over God are licensed. If not, the license is denied.
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Empiricist: Theism is out by the entrance policy. Even miracles won’t help unless “God” is part of the observation report rather than a theoretical gloss (“I perceived a burning bush as God” won’t do). This convention thus sharpens, rather than settles, the debate: theists must either change the convention or argue that God is an object of experience.
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Platonist: Theists enjoy a default yes, because the concept “God” is about a perfectly good, omniscient, omnipotent being, and for Platonists, well-formed concepts latch onto objects. The real work shifts to conceptual questions: coherence, consistency with other abstracta, and the logic of perfection.
The striking result is not that theism becomes arbitrary, but that it takes on different burdens. In a deflationary frame, the burden is sociolinguistic (is the practice legitimate?). In a Neo-Quinean frame, it’s explanatory (does God improve our best theories?). In an empiricist frame, it’s methodological (does God meet the experience test?). In a Platonist frame, it’s conceptual (is “God” coherent?).
Why philosophers talk past one another
When conventions are left implicit, debates devolve into moving goalposts and ad-hoc exceptions. An empiricist will dismiss “God exists” as meaningless or unfalsifiable, while a platonist will regard that dismissal as a non sequitur because their convention recognizes non-empirical objects. A Neo-Quinean may reject God as explanatorily idle, while a deflationist sees ordinary theistic discourse as already licensing “exists” without theoretical detours. Each side sounds obtuse to the other because they’re enforcing different scorekeeping rules.
The cure is not to pick one true convention and outlaw the rest, but to make the convention explicit and defend it on the right grounds: not “Is God real?” (yet) but “Which convention of existence best serves the aims of this inquiry?”
Isn’t this just verbal?
Two common objections arise.
Objection 1: It reduces metaphysics to wordplay.
Reply: Conventions are not arbitrary; they are tools. A convention encodes epistemic standards (what counts as evidence), inferential norms (what follows from “there is”), and practical stakes (which commitments we incur). Choosing a tool is not trivial if the job matters. A surgeon’s choice of suture is “conventional,” but not arbitrary; it is justified by outcomes, safety, and cost.
Objection 2: It makes existence relative.
Reply: Relativity to a framework doesn’t collapse into anything-goes. Within a fixed convention, truth is robust and disagreement is genuine. Moreover, frameworks can be compared by meta-criteria—explanatory power, simplicity, integrative capacity, fruitfulness, and ethical consequences. If a convention persistently misclassifies, obstructs inquiry, or generates needless mysteries, that counts against it.
Practical payoffs: clarity, translation, and comparability
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Declare your bookkeeping. Philosophical and theological arguments should begin with a short “existence policy”:
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Terms licensed: Which categories may be counted?
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Evidence rules: What observations or inferences are admissible?
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Burdens of proof: Who must do what to assert “there is”?
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Translate across frameworks. Provide a manual that restates key claims under rival conventions. Examples:
- Deflationary → Neo-Quinean: “Our practice licenses ‘God’” becomes “There exists an entity required by the best [moral/meaning] theory that plays the God-role.”
- Neo-Quinean → Deflationary: “God is explanatorily idle” becomes “No established practice with good standing licenses ‘God’ beyond expressive convenience.”
Translation exposes where genuine disagreement lies (e.g., over theory choice) and where it doesn’t (e.g., over the grammar of “exists”).
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Compare by shared virtues. When picking a convention for a domain, argue that it is:
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Empirically apt (tracks the data that matter for that domain),
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Explanatorily powerful (yields unified, predictive, or illuminating theories),
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Ontologically economical (no gratuitous posits),
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Ethically responsible (doesn’t systematically obscure moral saliences), and
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Practically fruitful (guides inquiry and action).
Different domains may legitimately adopt different conventions: empiricist for lab science, Neo-Quinean for theoretical unification, deflationary for ordinary and institutional reality (money, laws, committees), platonist for mathematics and certain modal discourses. Disputes become boundary questions: where does one convention’s competence end and another’s begin?
A brief case study: theism under mixed conventions
Suppose we’re doing moral philosophy. Two rival packages present themselves:
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Secular Neo-Quinean: Our best moral theory quantifies over reasons, values, and persons, but not God. God is explanatorily idle: adding theistic posits does not improve fit or simplicity.
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Theistic Neo-Quinean: Our best moral theory is a modified divine command or perfect-being account: it explains moral authority, obligation’s bindingness, and the unity of value better than secular rivals. God is the best explanation of moral normativity.
Under either package, the empiricist will say both are off-policy (no direct sense data of normativity either!), while the platonist will say both are under-ambitious (values and God both exist as abstracta). A deflationist will ask whether our actual moral and religious practices license “God”—and whether those practices survive critical reflection.
Notice how the debate sharpens once conventions are on the table. Parties can now argue about the right convention for moral theory rather than trade unmoored slogans about “evidence” or “reality.”
Why theism is the canary
Theism sits where our linguistic practices, theoretical ambitions, and experiential limits intersect. It is richly embedded in communal language (favorable to deflationism), centrally relevant to grand theories of value and meaning (a live option for Neo-Quineans), beyond sense experience (at odds with empiricism), and conceptually lush (welcome under platonism). Because it touches all four, whether “God exists” comes out true will often be a function of where we set the dials. That isn’t a cop-out; it’s a diagnosis of why debates about God persist despite brilliant arguments on every side.
A proposal
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Require a preface. Every paper or debate making existential claims should include a short “Convention Statement” specifying which rulebook is in force and why it is apt for the domain.
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For theism, use a two-tier approach.
- Public-reason tier: argue under a broadly Neo-Quinean convention (what do our best, shared theories require?).
- Practice-respect tier: acknowledge deflationary verdicts about religious discourse (what does our actual language license?), then assess those practices by their epistemic and moral merits.
This keeps shared inquiry possible while respecting the lived grammar of religious life.
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Maintain translation tables. When presenting an argument for or against God’s existence, offer parallel statements under rival conventions. This disciplines rhetoric and reveals where pressure should be applied (conceptual coherence, evidential policy, or explanatory virtue).
Conclusion
“Existence” is not a metaphysical spotlight that passively illuminates what’s out there. It is a carefully regulated linguistic device that lets us keep track of commitments within practices, theories, experiences, and concepts. Once we make our convention explicit, we can say with clarity why “God exists” is sometimes true, sometimes false, and sometimes out of play. That clarity doesn’t end the debate; it lets us have the right debates: about which convention best serves our purposes and where, if anywhere, the theistic posit earns its keep.