What exactly is metaphysics?

A reader writes:

If you had the time, I wanted to request a topic on philosophy as it relates to apologetics.  I’m hoping you could answer: “What exactly is metaphysics?A lot of debate I’ve seen online, and in reading apologists work (especially Craig) you find a lot of talk aboutmetaphysics, what’s “metaphysically absurd”,  “metaphysically counter-intuitive”, “metaphysically necessary”, or “has a metaphysical reality”.  I sort of understand what it is, but I’m really not clear exactly, other than having the impression that modern philosophers generally avoid it.

From what I can tell, it seems to be a tool apologist philosophers love since they can dress their religion up inmetaphysical terms to try and give their claims some legitimacy.   I figure since you obviously know quite a bit on philosophy, it’s something you could illuminate for those of us who only have a basic understanding of philosophy.

Answering the first part of the question requires doing some history of philosophy. Aristotle wrote some books we now know as the Physics, and he also wrote some books we now know as the Metaphysics, literally “after the physics.” This probably wasn’t Aristotle’s title for the books. The idea seems to have been that if you’re studying Aristotle, you should study the Metaphysics after you study the Physics, though I’ve also heard this is just the order the books were shelved in.

So for a l0ng time the word “metaphysics,” when it referred to a subject matter, referred to the subject(s) discussed in Aristotle’s Metaphysics. But the word has since drifted away from this meaning, to the point that now, nobody has any idea what it means. Well, that’s an exaggeration, but only by a little bit. Even leading metaphysicians admit they don’t have a good definition of “metaphysics.” The best definition I can give is “a bunch of questions about reality that don’t go anywhere else.”

As for the specific phrases mentioned above, “metaphysically necessary” is the only one where I know of a clear meaning for it off the top of my head. The idea is this: some things are impossible because they violate the laws of physics. But there’s an important sense in which the laws of physics could have been different, or they could even in fact turn out not to be the whole story, so we need a broader sense of “possibility” to cover that.

But then (so the standard story goes) there are things that aren’t even possible in that broader sense. For example, there’s no possibility that the laws of logic could have been different in the sense that the laws of physics could have been different. That thought led to philosophers talking about things being “logically impossible” if they involve a contradiction, and “logically possible” otherwise.

And then some people think an idea can be as impossible as impossible can be without involving a logical contradiction, and they call that kind of impossibility “metaphysical impossibility.” Things that aren’t impossible in that sense, then, are “metaphysically possible.” And things that couldn’t possibly have been otherwise, in that sense, are “metaphysically necessary.”

Now there’s some debatable claims about the nature of possibility in the rationale for those definitions, so you don’t have to accept them, but that at least tells you what the heck philosophers are thinking. As for the other phrases, I had to write back to ask for a link to the context they had appeared in. The reader wrote back with some stuff William Lane Craig has written, which wasn’t particularly enlightening. I’ll do my best here, though.

My guess is that “has a metaphysical reality” means something like “has a reality beyond time and space.” The other two, “metaphysically counter-intuitive” and “metaphysically absurd,” sound to me just like fancy-pants ways of saying “counter-intuitive” and “absurd.” In fact, I can’t find any instances of the phrase “metaphysically counter-intuitive” being used by anybody except William Lane Craig. (Though to be fair, many philosophers consider being counter-intuitive to be a serious blow against a philosophical idea.)

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