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The Kalam Cosmological Argument: Part 2 (William Lane Craig)

Information: This is part 2 of a review of the Kalam Cosmological Argument (KCA), as presented and defended by the evangelical theologian William Lane Craig. Click here to read Part 1. All quotes are by William Lane Craig unless otherwise noted. A version of this article was originally published on the website www.faithnet.org.uk.

The argument based on the impossibility of the formation of an actual infinite by successive addition

Potential Infinite - Something which is not infinite now (i.e. it is in the process of becoming infinite). It will achieve infinity in the future.

In the argument based on the impossibility of an actual infinite, William Lane Craig set out reasons as to why it is logically impossible for an actual infinite to exist. Actually, he set out reasons to support why (logically) the world and the universe cannot always have existed, and we used the examples of dates, times and numerical sequences to illustrate this.

If you are unsure why dates, times and numerical sequences are evidence against an actual infinite, click here.

So if the universe is not infinite now, maybe it is becoming infinite (i.e. it is potentially infinite)? Well, William Lane Craig rejects this idea too, for the simple fact that (as we have just seen) to add to something to something else implies there is a beginning to all this.

0 + 1 + 2 + 3 +4 + 5 + 6 etc. = infinite sequence of numbers

To think of this another way... one has to begin somewhere, in order to start drawing a circle!

So to say something is potentially infinite, appears to be equally problematic. Either something is infinite, or it is not!

In terms of the universe then, if this had no beginning then it would have to be infinite now. However, we discussed some of the problems associated with this notion in Part 1. Even if we change this to say that the universe had a beginning but will be around from this point on (i.e. it will be infinite from now on), gets us nowhere, and in fact seems to be saying two incompatible things (i.e. the universe is not infinite, but will be!).

Infinite - That which has no beginning or end. Something which is infinite can also be said to be complete (i.e. it contains all of its possibilities).

So taking all this into account, it should now be clear why William Lane Craig rejects the notion of an infinite universe, in favour of one with a definite starting point in time. It is simply impossible for him to see how it could be any other way! Furthermore, if the world and universe began at a certain point in the past, this would appear to require some 'other cause' to bring it into existence (which William Lane Craig ultimately believes is God):

'On the basis of the Kalam Cosmological Argument, I conclude that it is rational to believe that God exists.'

Supporting evidence

A graphical representation of the expansion of the universeAlthough the KCA is strictly a rational argument, like other cosmological arguments it can find support in modern 'Big Bang' cosmology; this stating that everything in the universe came from an initial singularity (i.e. a 'starting-point'). It is also supported by the second law of thermodynamics (SLT), which states that things will eventually reach heat equilibrium (i.e. the temperature of something will become the same everywhere, meaning that in the end 'hot' and 'cold' as measurable quantities will cease to exist). This means that if the universe did not come into existence at a definite point in the past, the SLT begs the question as to why it is not in a state of heat equilibrium now.

If the universe is infinite, then it cannot be said to be cooling down from an initial heat surge (i.e. the 'Big Bang'). In fact, more reasons would seem to needed as to why some things are 'hot' and others 'cold' at this moment in time, if the universe had no starting point to it.

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Some critiques of the Kalam Cosmological Argument

Picture of a SlinkyA possible contention to the worldview on which the KCA is grounded, could be the notion that the universe is oscillating from an expanding to collapsing state over an infinite period of time. This description of the universe has been dubbed the Oscillating Universe Theory (OUT), and although not a popular cosmological model of the ways things are, is still one possible theory of the way things might be.

In fact, the OUT directly challenges the KCA notion that one cannot have an infinite x, at the same time a having a finite sequence of y. For example, although modern cosmology states that our present universe had a beginning (y), this might be one expression of an infinite number of possible universes (x).

However, the biggest objection to the KCA (as William Lane Craig presents it), is when God is slipped in at the last minute to explain why we have a world and a universe in the first place:

  • Whatever begins to exist, has a cause of it's existence (i.e. something has caused it to start existing).
  • The universe began to exist.
  • Therefore, as the universe is something which exists, it must have had a cause of it being here (which William Lane Craig would obviously say was God).

The problem here is that God is not required to provide reasons as to why anything is here. In fact, modern cosmology is grounded precisely in the notion that everything came from nothing, and that prior to the singularity which caused our present universe to come into existence, there literally was nothing (no-thing) there. So science provides a perfectly adequate naturalist account of the origins of the universe, which does not requires us to posit the existence of anything prior to it being here in order to justify why it now does.

Furthermore, tagging God onto the end of statement 3 (as William Lane Craig wants to do), is something which makes the argument invalid. For unless one can show that God is needed to validate statements 1 and 2, it would not be correct to infer the conclusion that statement 3 leads us to posit God's existence. If William Lane Craig wants to do this, then he would appear to require a revised form of the KCA:

  • Whatever begins to exist has [God as] a cause of its existence.
  • The universe began to exist.
  • Therefore, the universe has a cause of its own existence [which is God].

It is only by adding [God as] to statement 1, that we can logically infer that God is the cause of the world's existence in statement 3. However, in doing this we need to begin by presuming God exists, prior to using the KCA as a basis for justifying God's existence! Yet if we do this, we are left with a circular argument.

Unless we presume that God exists, the KCA appears unable to go beyond anything more than saying the world and the universe cannot be infinite (which is what scientists have been saying for years now anyway).

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