I recently read Peter Kreeft and Ronald K. Tacelli’s Handbook of Christian Apologetics, an intelligent and well-written summary of various arguments for the truth of Christianity. It was recommended to me by Bruce Charlton, and I pass the recommendation on to anyone who has more than a passing interest in religious questions. Kreeft and Tacelli write in a very clear and engaging style, and they helped me see the force of some arguments that I had long dismissed.
The book begins with a series of 20 different arguments for the existence of God (available online), and I’ve decided to go through each of them, one at a time, and attempt to evaluate their validity. I’ll be posting my thoughts and conclusions on this blog.
Why I’m doing this
God, as conceptualized by the philosophers and orthodox theologians, is an idea I’ve never properly considered.
Although I was formerly very religious, the religion I was raised in (Mormonism) worships a physical being which happens to exist as part of the universe but has no metaphysical significance — a God only in the sense that Hercules could be called a god. There is no place for the God of the theologians. Because the Mormon God plays no philosophical or metaphysical role, there can obviously be no philosophical argument for his existences. His existence is an empirical inference based primarily on the subjective data of personal religious experience. As a believer, I had of course encountered the classical “proofs” of God’s existence but dismissed them as irrelevant; the subject of the proofs obviously had nothing whatsoever to do with the God I knew.
Later, when I concluded that the available evidence wasn’t consistent with Mormonism after all, I slipped very naturally into the atheistic materialism to which Mormonism is (in theory, though of course not in practice) so closely allied. I continued to dismiss the arguments for God’s existence — after all, even as a believer I had been able to see they were bogus! It took me a long time to realize my fallacy, to realize that I had never really been a theist in the sense that creedal Christians are theists, and that I had never really given the question of God’s existence any serious consideration.
I now intend to rectify that omission. Kreeft and Tacelli’s list of arguments offers a convenient framework for doing so. I will begin, in this post, with the first of the 20: the Argument from Change.
Summary of the argument
The original argument as it appears in the Handbook can be found here. (The real original comes from Aquinas, of course, but I will be evaluating it in the form in which K & T present it.) Below is my summary of the argument as I understand it. I’ve rephrased some things in more congenial terminology, but I think I’ve remained true to the substance of the original.
- Whenever a given system changes from one state to another, the change must have been caused by something external to the system itself. This is because “Nothing can give itself what it does not have, and the changing thing cannot have now, already, what it will come to have then.”
- The universe (“the sum total of all matter, space, and time”) is itself a changing system.
- Therefore, something (call it Q) must exist which transcends the universe (matter, time, and space) and causes it to change. Otherwise the universe could not change.
- Because Q transcends time, it does not itself change. (This obviates the need for an infinite series of meta-Q’s.)
- A “real being transcendent to the universe” is “one of the things meant by ‘God.'” So Q could be God.
This whole genre of argument — highly abstract, relying on seemingly obvious generalizations, and leading up to a counterintuitive conclusion — reminds of nothing so much as the famous paradoxes of Zeno of Elea, and for that reason alone I would be wary of leaning to heavily on it, even if I could find no fault with the reasoning itself. But I do find several apparent faults.
“Nothing can give itself what it does not have.”
Given that any system consists of a number of interacting parts, why is it impossible for a change of state to be internally caused? Kreeft and Tacelli explain it thus:
Nothing can give itself what it does not have, and the changing thing cannot have now, already, what it will come to have then. The result of change cannot actually exist before the change.
This is a bit obscure, but what they seem to mean is this:
- Suppose system S comes to be in state p, a state it was not in previously.
- Suppose further that the change to state p was caused entirely by things internal to S; then we could say that S “gave itself” state p.
- Nothing can give what it does not have. Therefore, S already “had” state p before it “gave” it to itself.
- What can it mean for a system to “have” a state but for it to be in that state? Therefore S was already in state p before it came to be in state p, which is absurd.
- Therfore, the change must have been cause by something external to S.
If this is indeed what Kreeft and Tacelli intend (and I’m kind of hoping I’ve misunderstood them), the argument depends on a very strange conception of causality — one which views states as unanalyzable units which never come into being but are merely passed from one system to another. If a system comes to be in a particular state, that state must have been “given” to it by something which was already in that state.
A concrete example should make it clear that this is an inadequate way of conceptualizing causation. Suppose a billiard ball hits a wall and changes its velocity. What gave it the new velocity? It couldn’t have been the wall, because the wall didn’t have that velocity and therefore couldn’t have given it. Suppose nothing in the entire universe had that particular velocity until the ball came to have it. Then what? Did Q give the ball its new velocity? But if Q is immaterial and atemporal, it obviously can’t have any particular velocity and therefore (by this logic) can’t give anything any particular velocity. So even if we grant this very bizarre model of causation, it undermines the conclusion of the argument: that Q is the ultimate source of all change.
Eternal cause, temporal effect?
But suppose we grant for the sake of argument that a changing universe cannot be accounted for without postulating something outside of the universe. Does Q — a hypothesized entity which transcends space and time — offer an adequate explanation of the changes we observe?
I don’t see how it possibly can. Q is supposed to transcend the universe and thus to be timeless — but each of the changes we observe in the universe takes place at a particular point in time. How can a change which takes place in time (as it must, that being part of the definition of change) be explained by a cause which is eternal and unchanging? If the sufficient conditions for a given change have always been in place and will always be so, world without end, then what accounts for the fact that the change takes place at this time rather than that one? How can an eternal and unchanging cause account for anything other than an eternal and unchanging state of affairs? Q just doesn’t seem to be the kind of thing that could possibly cause anything to change.
Changing system + something else = a bigger changing system
But suppose we grant for the sake of argument that Q is in fact a necessary and sufficient explanation of the fact that the universe changes. Then is everything accounted for?
Apparently not. While Q itself does not change, the system comprising Q plus the physical universe (call it the meta-universe) does change — and, ex hypothesi, any changing system requires something outside of itself to account for the fact that it changes. So we need to postulate a meta-Q to explain the changing meta-universe, and so on ad infinitum. The series will necessarily be infinite because (1) if any part of a system changes, the system itself changes; and (2) a system plus something that interacts with it necessarily constitutes a larger system.
Since an infinite series of nested universes doesn’t explain anything, there must be something wrong with the premise that a changing system must be changed by something outside the system.
My goal here is to really understand and fairly evaluate these arguments, not to “win” on behalf of atheism. If I’ve misunderstood the argument, or if my objections miss the point, I hope someone will leave a comment and set me right.