Cogito ergo sum, right?
A chief goal of religious apologists, and indeed, any philosopher that plays in ontology, is to demonstrate logical necessity that something must exist. The problem with this is that it puts the cart before a really big horse. The following commentary on this phenomenon appears largely as is in a comment on John Loftus's Debunking Christianity blog, on a post about the use of mockery and ridicule.
Generally speaking, I find this to be an enormously common fallacy, more
common the more of a philosopher one considers him/herself to be. Again, this error is not limited to theists, though exceptionally common amongst them since ontological arguments are often central to their efforts.
Indeed, as weird as it is, a philosopher could prove "logical necessity"
for the existence of some entity, say a deity, and yet no such entity must actually
exist. If the logic used doesn't really match reality, we can prove all
sorts of things are logically necessary and yet physically meaningless.
Indeed, it is actually easy to think of examples of this if one is properly
prepared for and then spends any serious time studying
mathematics, particularly transfinite math. Take, for instance, numbers that are so large as to be essentially meaningless, and I'm not talking about cute little big numbers like googolplex or Skewes's number. Sure, those are fantastically big, but they're smaller than most. There's an entire branch of mathematical philosophy known as "ultrafinitism" that says that at some point, those numbers really don't mean anything. Certainly, just because we can produce some sort of notation that indicates what they are, and because the axioms underlying number theory guarantee that they "exist," it is not incumbent upon the universe to produce or house any sort of structure that can be enumerated by those numbers. Indeed, it is easy to come up with numbers that dwarf any number that can represent the size of anything that a finite universe can create (as the countable infinite cardinal represents a strong limit cardinal, if you want to know why).
Other examples are copious: what do fractions of super-large numbers really mean in reality? How about irrational real numbers like π (which is also transcendental)? One could argue that π must exist in the universe because of how useful it is, but that's not correct if very, very good approximations of it (say to millions or billions of decimal places) are actually what's really going on (i.e. there is no requirement on the universe for a perfect circle to exist). What about the infinitely many infinities? At some point, even if the universe is infinite, logic dictates that there exist concepts with sizes that are literally beyond comprehension. Must these exist because logic says so? Or is it more reasonable to see logic as what it is: a construction that allows us to create an abstract representation of reality, rather like a map, and even extend it beyond reality's true boundaries?
To emphasize: "This must necessarily exist" only
ensures the abstraction, which exists in a logico-axiomatic framework,
we're talking must necessarily "exist" in the abstract sense and confers
no responsibility on reality whatsoever.
Reality is not
dictated, nor is it influenced, by our logical constructions. Indeed, it is the other way around, as is so often the case with really good illusions (like the illusion of intelligent design in the natural world). Our entire conception of logic has been built around the idea of how we
see the universe, not the other way around. The universe appears to
follow logical rules because while formulating what has become logic, if what we were saying didn't really match up with how the universe works, we called it
"illogical." Sure, we've extended that now into the purely abstract, but
all of our basic axioms (from which logical systems get their utility)
ultimately have to be grounded in our best guesses about reality itself. Furthermore, the responsibility rests on our shoulders to realize that our abstract representations, though very, very useful (and thus justified), are abstract representations of reality, not statements about reality itself.
All along, it's been our system of attempting to understand the world (which is all logic is) getting
nudged into a neater and neater fit, so far as we can tell, by the
brute force of a non-agent universe (I'd say "an indifferent universe,"
but some fairly annoying Christian apologists have already proved to me that they try to exploit
that term as if I'm implying agency by saying "indifferent"--sickeningly
Now is an exciting time of sorts. We face a problem in that our highly
successful map to reality (logic, and its fruits) has run into one of these places
where, ultimately, we may have to reexamine the foundations of our intellectual cartography. Quantum mechanics presents evidence from reality that can be
described with the tools we have, but it appears not to be able to be
properly understood. It's possible that nature doesn't really present
the basis the kind of logic we've been pretending it does all along.
This means it's a good time to impress the lesson again: the universe,
reality, is not subject to our logic. Our logic is an abstract construct
via which we attempt to understand what actually is.
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