The Kalam Cosmological Argument has as its first premise "Everything that begins to exist has a cause" (at least in the form I've heard it). Often examples of "chairs" or "people" are given for things that began to exist. But this seems to be a category error - the Universe did not begin to exist in the same way that a chair does. Indeed a chair doesn't "begin to exist" in that it was created from other things.
So to me it sounds like the argument overstates its case with "everything that begins to exist" since the only thing that has begun to exist is, well, everything. One could restate this premise as "The universe began to exist" could it not?
Is I missing something or is this what is meant by this argument? If so it seems to be more of an assumption than the inductive reasoning I hear it being used as (e.g. "you've never seen a chair 'pop into existence' have you?").
I think you've put your finger on a dubious feature of the KCA. While I would say that a chair does begin to exist when it's created from pre-existing materials, I agree with you that if the universe began to exist, the universe didn't begin to exist in the same sense in which a chair does. So I think you're right to detect a questionable move from "Everything within the universe that begins to exist has a cause" to "Everything, including the universe itself, that begins to exist has a cause." It's not at all clear that the phrase "begins to exist" is being used in the same way both times. To the question "You've never seen a chair pop into existence, have you?" one can reply as follows: "I've never seen anything arising from pre-existing materials pop into existence, but that isn't relevant to whether something not arising from pre-existing materials can pop into existence."