A Summary of Craig's Reply to Mackie's Critique of the Kalam

http://www.leaderu.com/offices/billcraig/docs/mackie.html

In the above cited paper Craig replies to Mackie's posthumously published tome "The Miracle of Theism". Specifically, Craig responds to Mackie's attack on Craig's Kalam Cosmological Argument. I will summarize, with too many direct citations to properly mark, Mackie's critique and Craig's reply.

The Kalam goes like this:

1. Whatever begins to exist has a cause of its existence.

2. The universe began to exist.

2.1 Argument based on the impossibility of an actual infinite:
2.11 An actual infinite cannot exist.
2.12 An infinite temporal regress of events is an actual infinite.
2.13 Therefore, an infinite temporal regress of events cannot exist.
2.2 Argument based on the impossibility of the formation of an actual infinite by successive addition:
2.21 A collection formed by successive addition cannot be actually infinite.
2.22 The temporal series of past events is a collection formed by successive addition.
2.23 Therefore, the temporal series of past events cannot be actually infinite.

3. Therefore, the universe has a cause of its existence.

Mackie objects to both premises, starting with the second.

The second premise is traditionally defended by saying that an infinite spatial or temporal distance cannot be traversed. Craig's version of this argument is found in premise (2.2) If it is posited that the universe has always existed, then it must be that the time the universe has existed is infinite. Since an infinite time cannot be crossed, today cannot be reached. However, today has come to pass, therefore the universe cannot have existed eternally, but must have had a beginning.

Against this Mackie says that the argument assumes a beginning point infinitely far away, and then argues that the distance between it and today cannot be traversed. Mackie contends that this fails to take infinity seriously, for from any point in the past there exists only a finite distance between it and today.

Against Craig's (2.1) argument, Mackie says that it fails to reflect a complete understanding of infinite set theory. The alleged absurdities that Craig draws from the notions inherent in the concept of infinity can be coherently explained by advanced mathematics. Our simplified understanding of "smaller" and "equal to" don't fully take into account the differences in adding and subtracting from sets versus adding and subtracting single members.

Against premise (1), Mackie says that there is no strictly logical a priori reason to assume that an undetermined event is utterly impossible.

Mackie goes on to say that in fact, the doctrine of creation ex nihilo is problematic. If God had a beginning, then we run into the same question of causality. If God always existed, then we run into the same problem of infinite regress. If God doesn't exist in time, then we are left with something extremely mysterious.

Mackie asserts that the best way to go for the theist is to use the empirical evidence available to support the idea that the universe had a beginning. However, this position has a problem too: such a position assumes that God's self-existence and omnipotence are self-explanatory. Why should we prefer the mystery of God's self-existence to the mystery of the universe's self-existence? it begs the question.

Mackie argues that if we prefer to believe that the Big Bang had a cause, then we should begin to doubt that the Big Bang was the beginning. In other words, we should prefer that the Big Bang had a material cause to the silly notion that the Big Bang had an immaterial cause.

In summary, Mackie contends that the notion of Divine Creation is only temporarily satisfying until thoroughly examined, under which circumstances it is best abandoned.

Craig says that against (2.2), Mackie's rebuttal is a straw-man. For Mackie calls it a prejudice against infinity, while (2.2) does not deny the possibility of infinity, only the inability to reach it by successive addition. If infinity may be instantiated, then it cannot be reached by counting one at a time, or by days passing one at a time.

Regarding Mackie's contention about proponents of the Kalam assuming a beginning point of the universe infinitely far away, Craig says that he does not know of any proponents who do this. In fact, it is the proponents of the Kalam that are the ones who take infinity seriously, by arguing that if the universe has always existed it has no beginning point. This notion demonstrates just how difficult it is to even coherently imagine. For, if the universe never had a beginning, how could it have begun? How could we even begin counting the days between today and the "beginning" of the universe? The number of days is "infinite", or absurd to even think about counting, much less traversing!

Craig then offers Zeno's paradox of Achilles and the Tortoise. But in the case of the eternal universe theory, it would be as if Achilles had to cross an infinite series of intervals, from a beginningless and open end. Therefore it is unlike the tradition paradox, because in it Achilles only had to cross a finite distance in an infinite number of intervals.

The fact that the universe has no beginning, according to Mackie, makes the difficulty in rebutting the Kalam worse, not better.

Craig then demonstrates why a collection of the order-type *w is non-constructible, and therefore there is not reason to think it can represent an infinite series of past events.

Craig then turns his attention to Mackie's comment about a given point in the past having only a finite distance between itself and today. He remarks that this is a red herring, being completely irrelevant. For, even granting such point, the proponent of the Kalam requires an answers as to how the entire series may be traversed, not a given finite segment of it!

Then Craig addresses Mackie's contentions about coherent, non-Euclidean set theory. Craig makes the point that even if infinite set theory is mathematically coherent, there is no reason to suppose such infinities can obtain in the real world. If such infinities were instantiated in the real world, they would create logical absurdities like those found in Hilbert's Hotel.

Craig goes on to actually admit that even a proponent of the Kalam may grant the principle of correspondence in lieu of Euclid's theorem, and remind us that it brings no ontological commitment regarding the real world. It isn't as if we have any example of a real infinite collection sitting around somewhere.

Craig then points to all of Mackie's humble admissions that not every professional will grant his views, and that scientific evidence has in fact turned up plenty of support for the idea of a finite past for our universe.

So Craig continues working through Mackie's contentions by looking at Mackie's call for an argument in support of (1), that everything with a beginning has a cause. As Mackie had cited Hume, Craig digs into Hume's writings to pull out full-fledged contentions amounting to the premises of the Kalam! He then repeats his favorite line about how giving an argument for this premise might be unwise, as one ought not try to prove the obvious via the less obvious.

Does the reader of this really actually believe that at any moment an object like a Tiger may simply pop into existence right in front of him, uncaused? Can a whole universe simply pop into existence like that? Can God pop into existence? How does such a believe prove useful or explanatory or even remotely rational?

Craig then ceases to pull philosophical punches, and concisely unveils the view he takes on God and creation. Such view seems to avoid Mackie's critiques about the existence of God raising even more problems.

Craig states his view thusly:

...God without creation exists changelessly and timelessly with an eternal determination for the creation of a temporal world and... with creation God enters into temporal relationships with the universe, time [arises] concommitantly with the first event. This may be mysterious in the sense of being wonderful or awesome, which indeed it is, but it is not so far as I can see unintelligible, as is something's coming into being uncaused out of nothing.

Craig then briefly delves into modern cosmological science, which actually supports the doctrine of creation ex nihilo. In order to make his case, it is incumbent upon Mackie to produce an alternate model of the beginning of the universe to the orthodox one. Craig briefly undercuts oscillating models of the universe.

Craig concludes with this, second-to-last paragraph:

What is Mackie's counsel? We should infer that the universe must have had some physical antecedents, even if the big bang has to be taken as a discontinuity so radical that we cannot explain it, because we can find no laws which we can extrapolate backwards through this discontinuity.' Here I think we see more clearly than ever the quasi-religious character of Mackie's atheism. Either we believe that the universe came to exist uncaused out of nothing or else no matter what the empirical evidence for an absolute beginning, no matter how deep a caesura we have to carve in nature, we should infer that the universe must be eternal. The existence of a creator God is not even an alternative. The theist can hardly be blamed for not impaling himself on the horns of this dilemma. On the contrary, in light of the foregoing discussion, of the three options, theism seems the most plausible route to take.