*This is part of my series on debugging the ontological argument.*
Let's take a little break from ontological arguments, and switch to math. Consider the following proof.

Theorem: Given a square, opposite sides are parallel.

Proof:

By definition, a square is a rectangle with all equal sides

By definition, all the corners of a rectangle are right angles.

In the following figure of a rectangle, line AB and CD are cut by transversal BC.

By the consecutive interior angles theorem, AB and CD are parallel.

There's something very wrong with this proof.
Logically speaking, it's completely valid and sound, and I can't really
think of a better way to prove the theorem it intends to prove. But
think about it: Why are we only proving the theorem for

*squares*?

The
entire proof rests on the fact that squares are a special kind of
rectangle. It's obvious that if we just replaced "square" with
"rectangle", we could prove a more general theorem, and use fewer
steps. "Given a

*rectangle*, its opposite sides are parallel."

This
isn't an issue of logic. It's an issue of aesthetics. My mathematical
training taught me to make the fewest assumptions necessary. My
training taught me to prove more general cases when I am able.

And that's why looking at the definitional ontological argument, I boggle.

$$\text{God is defined to have all the perfections.}\tag{1a}\label{1a}$$ $$\text{Existence is a perfection.}\tag{1b}\label{1b}$$
$$\text{If something exists by definition, then it
exists.}\tag{1c}\label{1c}$$ $$\text{Therefore, God
exists.}\tag{1d}\label{1d}$$

Earlier, we placed all our focus on the
inference \ref{1c}, because that's the most questionable step. But
let's also take a moment to focus on the abysmal aesthetics of \ref{1a} and
\ref{1b}.

The entire proof is based on the fact that God exists by definition. Why, then, is it necessary to assume that God has

*all* the perfections? It is sufficient to assume that God just has one perfection--existence.

^{1} If \ref{1c} were a correct inference, then we could prove a more general theorem, not just the theorem about God.

This
is a problem for most ontological arguments. They define God to have
all the perfections, or to be the most supreme being imaginable. In
Alvin Plantinga's version, he goes so far as to define a "maximally
great being" as omnipotent,
omniscient, and morally perfect in every possible world.

Any decent mathematician would look at these words and say, "Why bother?"

**Florid prose, or obscurantism?**
I
don't know what runs through the minds of philosophers who state
ontological arguments with patently extraneous assumptions. However,
the florid definitions of God do serve a purpose, whether intentional or
not.

The purpose is to prove only the special case of God, and
draw attention away from the more general theorem. Like with the
theorem about squares, it's as if the mathematician wants you to only
think about squares, and wants you to conveniently forget that the same theorem also holds
for rectangles.

If people realized that the ontological argument
works equally well for a large class of objects and not just God, then
they might just realize that the ontological argument proves some things
which are completely ridiculous. For example, The Flying Spaghetti
Monster is the most perfect cluster of noodles imaginable. Therefore it
exists.

I've made such

*reductio ad absurdum* arguments before, and I
find that ontological argument proponents dismiss them for various
reasons. For example, they would say the Flying Spaghetti Monster is inconceivable,
or that it is conceptually inconsistent.

This is all missing the point. When I look at the ontological arguments, it's clear that
all the premises about God being the greatest and most perfect being are
completely extraneous. If ontological argument proponents truly think that the ontological argument

*only* works to prove the existence of God and no other objects, then they clearly have some unstated premises.

In the next part of the series, I will be
considering Plantinga's modal ontological argument. However, the part
of the argument where he talks about omnipotence and omniscience, that
part will be dismissed and erased with contempt.

**Maximization arguments**
I
should mention, for technical completeness, that sometimes the "florid" definition of God does some work after all, creating what I call the Maximization Ontological Argument.

In the Maximization Ontological Argument, God is specifically defined as the greatest thing that is conceivable. Then it's asserted that a thing would be greater if it also exists. I suppose this draws on the intuitive assumption that given any ordered set of things, there must be a maximum. Of course, this assumption is just mathematically wrong (e.g. take the set of all integers, or the set of all irrational numbers less than one).

Even putting aside the fact that not all ordered sets have maximums, you can't simply assert things about a maximum on the basis that it would make it the maximum greater. For example, consider the greatest even number less than 10. Your first guess might be that the answer is 8, but consider that any number would be greater if you added 3 to it. Therefore, 11 is the greatest even number less than 10. I feel this argument is just flatly invalid, and doesn't really dignify in-depth discussion, so I'm going to move on.

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1.
It's also worth noting that the extraneous assumption
actively makes the proof weaker, because now we need the additional assumption that existence is a perfection.