# Aquinas's Third Way



## Filter (Nov 22, 2018)

I have perhaps a simple question concerning Thomas Aquinas's Third Way of proving God's existence. I've been reading Edward Feser's introductory book to Thomism, and he makes a statement that I'm a little confused by without stating any premises for it.

To quote from the book, he writes that "_for _(again, given at least an Aristotelian conception of possibility) _it would be absurd to suggest both that it is *possible *for every contingent thing to go out of existence together, and yet even over an *infinite* amount of time this will never in fact occur."_ 

Why is this? Especially concerning Thomistic metaphysics, potency can only be actualized by another external cause. Would it not be theoretically possible for no external cause to cause something that which exists to no longer exist? Therefore even over an infinite amount of time it is _possible_ for its potency to not exist to never be actualized?


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## Bill The Baptist (Nov 22, 2018)

Filter said:


> I have perhaps a simple question concerning Thomas Aquinas's Third Way of proving God's existence. I've been reading Edward Feser's introductory book to Thomism, and he makes a statement that I'm a little confused by without stating any premises for it.
> 
> To quote from the book, he writes that "_for _(again, given at least an Aristotelian conception of possibility) _it would be absurd to suggest both that it is *possible *for every contingent thing to go out of existence together, and yet even over an *infinite* amount of time this will never in fact occur."_
> 
> Why is this? Especially concerning Thomistic metaphysics, potency can only be actualized by another external cause. Would it not be theoretically possible for no external cause to cause something that which exists to no longer exist? Therefore even over an infinite amount of time it is _possible_ for its potency to not exist to never be actualized?



I think what he is speaking to is the inherent contradiction is claiming that something is both possible and impossible at the same time. You can’t cogently claim that something is possible and then also claim that it could never actually happen. If something is possible, then it could happen.

Reactions: Like 1


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## Filter (Nov 23, 2018)

Thank you for your response. I can see that that may be what he is saying, although the wording seems to suggest not only _could _it happen, but that it _would_ happen. It seems, superficially at least, that he isn't saying "if it is possible, it could happen", but rather that "if it is possible, than it _would_/_will_ happen given sufficient time".


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## Bill The Baptist (Nov 23, 2018)

Filter said:


> Thank you for your response. I can see that that may be what he is saying, although the wording seems to suggest not only _could _it happen, but that it _would_ happen. It seems, superficially at least, that he isn't saying "if it is possible, it could happen", but rather that "if it is possible, than it _would_/_will_ happen given sufficient time".



It’s actually quite a common belief in philosophy that, given an infinite universe, anything that is possible will eventually happen. This is actually one of the arguments that naturalists use against things like the resurrection, that if it were possible for people to rise from the dead then people would rise from the dead. There is actually no particular reason to accept this as being true, other than that it tends to lend credence to a naturalistic view of the origin of life.


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## Filter (Nov 25, 2018)

That is true. It is probably me needing to familiarize myself more with philosophical understanding and jargon. Thank you for your wisdom!


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