RE: Plantiga's ontological argument.
April 21, 2013 at 3:33 pm
(This post was last modified: April 21, 2013 at 3:35 pm by Shell B.)
Well, here is a rather succint sentence from the start of that article:
So, basically, it is saying that an argument can follow all of the logical steps that would lead us to a conclusion of "true," but that would only be in formality. It is vacuous because it assumes the truth of premise a, when, in fact, premise a is false.
An example,
If all dogs are purple, than all chihuahuas are purple. Well, this is a perfectly logical and true argument. However, A (all dogs are purple) is false. Therefore, this is a vacuous truth.
So, in the argument this thread is regarding, you have the first premise as "If x is possible, then it is necessary that x is possible." We'll ignore the fact that this is inherently untrue, as far as I understand the possible qualifier to work. Mind you, necessary is used often, but I have rarely encountered possible in my brief time dealing with this kind of logic. So, ignoring that, we have an empty truth. X is not necessarily possible. X in this argument is a necessary being. Given that we do not know if a necessary being is possible, the premise is false. Therefore, you have an argument that is logically sound, but vacuous or meaningless, if you prefer.
Quote:A vacuous truth is a truth that is devoid of content because it asserts something about all members of a class that is empty or because it says “If A then B” when in fact A is inherently false.
So, basically, it is saying that an argument can follow all of the logical steps that would lead us to a conclusion of "true," but that would only be in formality. It is vacuous because it assumes the truth of premise a, when, in fact, premise a is false.
An example,
If all dogs are purple, than all chihuahuas are purple. Well, this is a perfectly logical and true argument. However, A (all dogs are purple) is false. Therefore, this is a vacuous truth.
So, in the argument this thread is regarding, you have the first premise as "If x is possible, then it is necessary that x is possible." We'll ignore the fact that this is inherently untrue, as far as I understand the possible qualifier to work. Mind you, necessary is used often, but I have rarely encountered possible in my brief time dealing with this kind of logic. So, ignoring that, we have an empty truth. X is not necessarily possible. X in this argument is a necessary being. Given that we do not know if a necessary being is possible, the premise is false. Therefore, you have an argument that is logically sound, but vacuous or meaningless, if you prefer.
