The first order of business is to specify and clarify the conclusions of Geisler’s five arguments. Here are the conclusions in Geisler’s own words:
- Therefore, the universe was caused by something else, and this cause was God. (WSA, p.16)
- Therefore, there must be a first uncaused cause of every finite, changing thing that exists. (WSA, p.19)
- Therefore, there must be a Great Designer of the universe. (WSA, p. 20)
- Therefore, there must be a supreme moral Lawgiver. (WSA, p.22)
- Therefore, if God exists, then He must exist and cannot not exist. (WSA, p.25)
These conclusions need to be cleaned up and clarified, so that we have an accurate understanding of what they mean:
1a. The universe was caused to begin to exist (in the past) by at least one thing or being other than the universe (or some part or aspect of the universe) that existed prior to when the universe began to exist.
2a. There currently exists at least one uncaused cause for each finite, changing thing that currently exists.
3a. There existed (in the past) at least one Great Designer who designed some aspect of the universe.
4a. There existed (in the past) at least one supreme Lawgiver of laws of morality.
Claim (5) is a bit tricky, because it appears to be ambiguous. The ambiguous term in (5) is the word “God”, and I believe that Geisler commits the fallacy of equivocation in how he makes use of (5). Here are the two different ways of interpreting (5):
5a. If there is or ever was a being that was God (i.e. “the most perfect Being possible”), then that being must always exist and cannot not exist.
5b. If there is or ever was a being that caused the universe to begin to exist, then that being must always exist and cannot not exist.
If we interpret (5) as meaning the same as (5a), then this claim is irrelevant to Geisler’s case for God, because the antecedent of the conditional implies that “God exists now or God existed in the past” and none of Geisler’s other arguments show this to be the case. So, (5a) cannot be used to infer any other claims, and it is thus useless in his case for the existence of God.
On the other hand, if we interpret (5) as meaning the same as (5b), then Geisler can use the conclusion (1a) from his first argument and combine it with (5b) to infer that the cause (or causes) of the beginning of the universe “must always exist and cannot not exist”, which might be helpful to his case for the existence of God.
The problem with (5b) is that it appears to be FALSE. We can conceive of a being that caused the universe to begin to exist but then, perhaps due to the exertion required for that great feat, ceased to exist. If this is a logical possibility, then (5b) is FALSE.
In any case, Geisler has given us no good reason to believe that (5b) is true. The argument for (5) goes like this (WSA, p.25):
If God exists, we conceive of Him as a necessary Being.