Logic Cannot Bring Anything Into Existence

Theists sometimes claim that God is the originator of logic. Set that aside — it is unsupported and it is not the interesting question.

The interesting question is whether God's existence can be established by logical argument at all. The ontological argument says yes, and versions of it have been circulating since Anselm. I want to argue that the whole enterprise is misconceived a priori, before any particular argument is examined.

What Logic Is

Logic is the exploration of what follows from assumptions. That is its entire content.

Which means anything you can prove was already present, in some form, in the premises. A valid derivation does not add information; it makes explicit what the premises already contained. This is why logic is truth-preserving rather than truth-generating: garbage in, valid garbage out.

So if you succeed in proving that God exists, God was in your premises. Possibly well hidden — the ontological argument is ingenious about the hiding, packing existence into the definition of the thing whose existence is at issue — but there.

A proof cannot be more informative than the assumptions it starts from. If the conclusion is a substantive claim about what the universe contains, then a substantive claim about what the universe contains went in.

You May Assume Anything

The second half of the point, and mathematicians demonstrate it daily.

I can posit a space with a hundred thousand dimensions and derive its properties rigorously. The derivations will be flawless. They tell us nothing whatever about whether the actual universe has a hundred thousand dimensions.

I can construct a universe identical to ours but with an inverse-cube law of gravitation, and reason about it correctly. Physicists do exactly this when testing models — they build formal systems, derive consequences, and check the consequences against measurements. Most of the models fail, not because anyone made a logical error, but because the world declined to match.

That is the crucial observation. A derivation can be perfect as logic and false about reality, and the only thing that separates the two cases is observation. Logic constrains what follows from what. It has no channel through which it could populate the world.

Why This Settles It in Advance

Put the two halves together.

Anyone attempting to prove a being into existence by deduction is attempting something the tool cannot do. Not something difficult — something categorically outside what deduction is. The argument does not need to be examined in detail to know this, in the same way you do not need to check a proposed perpetual motion machine's gearing to know it will not work.

And this is not special pleading against religion. The same objection applies to any purely armchair derivation of a substantive fact about the world, from any tradition. If someone claimed to prove by pure reason that there are exactly seven planets, or that a particular element must exist, we would not evaluate the derivation — we would note that the conclusion is the sort of thing you find out by looking.

The existence of a being who created the universe is exactly that sort of thing. It is a claim about what there is. Claims about what there is are settled by investigation, and no amount of valid inference substitutes for it.

The Predictable Reply

The theist's move here is to say that God is different — a necessary being rather than a contingent one, and necessary beings are precisely the sort of thing logic can reach.

But notice what has happened. "God is a necessary being" is itself the premise doing all the work, and it is exactly as much in need of support as the conclusion it was introduced to deliver. You have not escaped the problem; you have relocated it into the definition and hoped nobody looks.

Which returns us to the first point. If the conclusion is in the premises, the argument establishes nothing that was not assumed. And if the premise is what needs defending, defend it — with something other than another derivation.