Descriptions and Existence: Did the Greeks Worship Zeus?

Core idea

A definite description is a phrase of the form the thing satisfying such-and-such a condition — "the man who first landed on the Moon", "the only man-made object visible from space". Following Bertrand Russell, logicians treat descriptions as a special kind of name: like proper names they aim to refer to an object, but unlike them they also carry information about it. "The man who first landed on the Moon" announces that whatever it refers to is a man and was first on the Moon.

That built-in information makes descriptions powerful — and dangerous. It seems to license the Characterization Principle: the thing satisfying a condition satisfies that very condition. Tautological as it looks, the principle is, in general, false.

Why it matters

The Ontological Argument, defined into a one-liner

The Ontological Argument says God has all perfections; existence is a perfection; so God exists. Strip away the disputed premises by simply defining "God" as "the being which is omniscient, omnipotent, morally perfect... and exists". The argument then collapses to a single sentence: the object which is omniscient, omnipotent... and exists, exists. This is an instance of the Characterization Principle — and it looks undeniable.

Why the Characterization Principle fails

It is not undeniable. Let the condition be "x is the greatest integer and x exists". The principle would hand us a greatest integer — though there is none. Let it be "x married the Pope"; the principle would prove the (unmarried) Pope is married. A principle that proves such things cannot be generally true.

Priest's argument: A definite description refers to an object only if there is a unique object meeting its condition; otherwise it is an empty name, and any subject-predicate sentence built on it is false.

"The greatest integer" refers to nothing because no such integer exists. "The Australian city with over a million people" refers to nothing because several cities qualify — uniqueness fails. The Characterization Principle holds only when the description actually refers.

The argument begs the question

So the Ontological Argument's one-liner is true if God exists — then the description refers, and each conjunct, including existence, holds. But if God does not exist, the description refers to nothing and the sentence is false. The very instance of the principle the argument leans on is reliable only on the assumption that God exists. To use it while trying to prove God exists is to beg the question — to assume exactly what is in dispute.

The crack: truths about Zeus

The standard account says any subject-predicate sentence with a non-referring subject is false. Yet it seems plainly true that the most powerful of the ancient Greek gods was called "Zeus", lived on Mount Olympus, and was worshipped by the Greeks. There were no Greek gods — so "the most powerful of the ancient Greek gods" refers to nothing. We are left with apparent truths about non-existent objects.

Key takeaways

Mental model

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Practical application

Before accepting an argument that hinges on "the X", check that "the X" actually refers: that something satisfies the condition, and that only one thing does. If either check fails, every flattering property packed into the description proves nothing. Definitions can introduce a name, but they cannot conjure the object the name needs.

Example

A consultant writes: "The strategy that maximises revenue with zero risk should be adopted." The phrase "the strategy that maximises revenue with zero risk" is a definite description, and adopting it as a premise quietly asserts that exactly one such strategy exists. If no zero-risk revenue-maximiser exists, the description is empty and the recommendation is built on a false subject. The Characterization Principle — "that strategy maximises revenue and carries zero risk" — holds only once such a strategy is shown to exist, not by naming it.

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