I’m having fun with critical examination of Norman Geisler’s Thomist cosmological argument in When Skeptics Ask. There is also a more detailed and in-depth presentation of this argument in Chapter 9 of Geisler’s much older book The Philosophy of Religion (1974).
I previously thought that the first premise of his Thomist cosmological argument was obviously true, but now I’m not so sure. I now think there are problems of UNCLARITY in the key terms “finite thing” and “changing thing.”
Below is a short fictional dialogue that I quickly constructed to explore some of my thoughts about what it means to say something is a “finite thing”.
I will return to my usual, more pedantic style in future posts.
Bradley: This pebble in my hand is INFINITE!
Norman: No it isn’t. It is a small object. I can plainly see that it is less than 1″ in diameter.
Bradley: True. It is not INFINITE in its size. However, it might still be an INFINITE thing. It might have INFINITE mass.
Norman: Nope. Plainly you are able to hold the pebble up with just one hand, so it must weigh less than 200 pounds. Since you are not straining at all to hold the pebble up with just one hand, it probably weighs less than 10 pounds. Assuming it is an ordinary pebble, given its size, it probably weighs less than 1 pound.
Bradley: OK. All right. The pebble has a finite size, and a finite mass. Perhaps it contains INFINITE energy.
Norman: If it contained INFINITE heat energy, you would not be able to hold it in your hand. It would instantly burn a hole through your hand.
Bradley: What if it had INFINITE electrical energy?
Norman: Then it would electrocute you and instantly fry your entire body like a billion lightning strikes hitting your hand all at once.
Bradley: You have a point there. Maybe it contains INFINITE kinetic energy.
Norman: I don’t think so. Kinetic energy depends in part on the mass of the object, and we have already established that the pebble has only a small amount of mass, and it clearly isn’t moving very fast, if at all.
Bradley: How about the past age of the pebble? Perhaps this pebble has existed for an INFINITE amount of time.
Norman: I doubt that. The earth is supposed to be about 4.5 billion years old, so the pebble is probably less than 4.5 billion years old (according to your godless evolution-infected geology).
Bradley: But you don’t know the history of this specific pebble. Maybe it came from another planet or from another galaxy. Can you prove that this pebble has only existed for a finite number of years?
Norman: Well, according to the Kalam Cosmological Argument, there cannot be an actually infinite number of days or years that have elapsed in the past.
Bradley: But if you need the Kalam Cosmological Argument in order to demonstrate the first premise of your Thomist Cosmological Argument, then you don’t have two independent arguments. Both arguments in that case would depend on the key claim in the Kalam argument that an actually infinite number of days or years cannot have elapsed in the past.
Norman: I’m confident of the truth of that premise of the Kalam argument, so I’m OK with making the success of both of my cosmological arguments depend on that premise.
Bradley: We have been discussing various common and easily observable physical attributes. Aren’t there lots of other possible physical attributes possessed by this pebble? In addition to being composed of molecules and atoms, it is also composed of sub-atomic particles, like: quarks, leptons, and bosons. Perhaps one of the properties of one of the sub-atomic particles in the pebble is INFINITE.
Do we know ALL of the kinds of sub-atomic particles that exist in this universe? I doubt it. Do we know ALL of the various properties of the sub-atomic particles that are currently known to exist? I don’t think so. Given that we still have a lot to learn about sub-atomic particles, I don’t see how (at this point in time) we can be sure that no sub-atomic particles in this pebble have any INFINITE properties.
Norman: I’ll admit that there is probably much that we have yet to learn about the kinds and characteristics of sub-atomic particles. But based on all of the ordinary physical properties that we are familiar with, which the pebble possesses in only finite amounts and degrees, and based on the properties of sub-atomic particles that we know about now, we should expect that new properties that will be discovered about the sub-atomic particles in pebbles, will also be possessed by the pebble in only finite amounts and degrees and NOT in INFINTE amounts or degrees.
Bradley: Perhaps all future discoveries about the properties of sub-atomic particles will be limited to properties that exist in only finite amounts and degrees, but we cannot know this ahead of time. Since there still appear to be some mysteries to unravel in the world of sub-atomic particles, what about the possibility that this pebble has an INFINITE number of physical properties? I don’t see how we can be certain that the number of physical properties possessed by this pebble is a finite number. Perhaps there is no end to the discovery of natural physical properties of this pebble.
Furthermore, since you believe that there is also a SUPERNATURAL realm, could it be that this pebble has some SUPERNATURAL properties, in addition to the natural physical properties it has? If so, then one of its SUPERNATURAL properties could be INFINITE. Can you prove that this pebble has no INFINITE SUPERNATURAL properties? Can you prove that you know ALL of the SUPERNATURAL properties that this pebble possesses? I don’t think so.