The second objection is that the Kalam is question-begging, i.e. it's circular reasoning. I've argued this myself on many occasions, so let's hear Dr. Craig put us atheists in our place:
Craig quite correctly states that one is only committing the fallacy of begging the question if the only justification for a premise is that one already assumes the truth of the conclusion, and then he claims that since he has given other reasons for believing that "everything that begins to exist has a cause" he his not guilty of the fallacy.
However, Craig is omitting an important detail – one which actually comes up again in this series, so I'll have more to say about it later.
"Causality" is a well-defined physical concept in science. Even if one is using the archaic Aristotlean notion of "Four Causes", Aristotle nonetheless inferred the existence of those four causes purely from the observation of physical things.
But if the universe had not yet "began to exist", in what sense could causality have been said to exist? Surely it cannot be the physical, temporal concept with which we are all familiar – since by definition in the argument, nothing physical or temporal existed. So we must be talking about some sort of non-physical or supernatural causality. Now, it's certainly possible that causality can transcend the physical universe, but that's no more remarkable than saying that it's possible we are all plugged into the Matrix and all reality is an illusion. As Craig himself has said, possibilities come cheap.
The question then is why we should assume that causality indeed does transcend the physical universe, because clearly such transcendence is necessary for the Kalam to be true. Unfortunately for Craig, the only reason to make such an assumption is to justify the conclusion of the Kalam! Craig is quite obviously guilty of begging the question.
This illustrates a crucial difference between the Kalam and the old "Socrates is mortal" argument that everyone learns in high school: we actually have robust empirical evidence that all men are mortal and that Socrates was a man. We do not have a shred of evidence that causality can transcend the physical universe – it's purely speculative, and most certainly not a well-established empirical fact about the nature of causality. And one cannot use a speculative assumption as a premise in a logical proof.
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Next: Part 3