Friday, June 7, 2013

Reasonably Faithless on Craig's infinite denial

Long-time readers may recall my extended series on the cosmological argument.  I recently discovered a post on Reasonably Faithless which deals with a few of the same points, but from more of a math perspective than a physics perspective.  We both agree that William Lane Craig really doesn't understand infinity.

For example, Craig argues that infinite numbers of real objects is impossible because if you take away an infinite number of objects, you could have a finite or infinite number remaining.  Here's an excerpt of Reasonably Faithless's response:
And I agree that you can’t stop someone from taking away a certain number of coins, no matter how big their coin collection is.  But there is no contradiction here at all.  To think otherwise is to grossly misunderstand what is going on.  The fact that ∞ - ∞ has no unambiguous meaning does not prohibit someone with an infinite coin collection from giving away infinitely many of their coins.  All it means is that the number of coins they have left after doing so will depend on which coins they gave away.