I don't understand the explanation of the third way here. I take the professor to be saying that if there is a possible world in which nothing exists this means that the actual world could not exist. Why would the possibility of nothing existing imply that nothing could exist in actuality? I'm sure I'm misunderstanding the meaning of possible worlds, but would be great is someone could clear that up.
Here’s my limited understanding: imagine we’re trying to refute this claim: ‘There could exist a possible world where it’s NOT EVEN POSSIBLE for anything to exist (neither necessary or possible beings).’ Well if that world were truly possible, then there could exist no world where there are beings. But there are worlds where beings exist, I.e our world therefore that initial claim is false. From there I think the argument goes on to claim that all possible beings come into being and therefore need an underlying necessary being to explain how they ultimately come into being. This not a temporal argument but a metaphysical 1 based on how possible beings come into being. Anyways sure there are better explanations, but this kind of helps for me.
@@markbirmingham6011 thanks but I still don’t get it 😅 I’m having trouble with the following implication: there could exist a world where nothing exists -> there could exist no world where there are beings. I don’t understand how the consequent follows from the antecedent. Why would the mere possibility of nothing existing imply that the actual world couldn’t exist?
As I understand it, the basic idea is that the space of ways that the world might have been doesn't vary with the particular state of the world. If it were genuinely possible for there to be a nothing-world, a state of affairs where nothing existed ('null-world'), then since such a world would lack any ground for the possibility of anything, nothing would or could in principle exist, given such a world. However, since the ways that a world might have been in principle don't vary no matter the state of affairs, if things are in-principle impossible in null-world, they are impossible in all realisable states of affairs, including the actual state of affairs. So if null-world is possible, there should not be anything. But there is something, so null-world is not possible. Since the idea that independent things don't have to exist implies the possibility of null-world, null-world being impossible entails the denial of the thesis that independent things don't have to exist. So there must be independent and necessary beings.
Yeah, it's a bit tricky, but let me try my hand at it: He's working on the (admittedly somewhat controverted) assumption that possibility and necessity are consistent across possible worlds. This is to say, what is possible/necessary in World1 is also possible/necessary in World2. Now, let's say we grant that there is a possible world (let's call is World$) where there is nothing at all. Since there is nothing in World$ - nothing to cause or be caused, nothing to change or be changed - then it is a world in which there are no possibilities aside from what is actual in World$ (namely, nothing). Combine that conclusion with the assumption mentioned above: If, in World$, there are no possibilities beyond World$, then, on the aforementioned assumption that possibility/necessity are consistent across possible worlds, it follows that only World$ is possible. Indeed, perhaps we can say that, necessarily, World$ is the only possible world. But World$ is an empty world, and our world most definitely is not empty. Hence, it is false that World$ is the only possible world. If we modus tollens the whole chain of reasoning back to the beginning, we would conclude that World$ is impossible, and, consequently, there must be some necessary being Who/Which exists in all possible worlds. To put it another way, they are effectively making a modal collapse argument and using that as a reductio to the assumption that only contingent things exist. To abbreviate the argument, it would basically look like: 1) If only contingent things exist, then World$ is the only possible world. 2) World$ is not the only possible world (on account of our world not looking like World$). 3) Therefore, it is not the case that only contingent things exist. All that being said, I have questions and reservations about the argument related to S5 modal logic and the issue of whether possible worlds are meant to include the actual world or rather function as a counterfactuals to the actual world. But all that aside, I think the above traces what they are trying to get at.
Much congratulations to Professor Bonevac, this is well-deserved for him.
What a great lineup of thinkers!
This was an amazing discussion. Very interested to learn more about these guys interpretations.
Quite the meeting of minds! I look forward to reading the book!
Great conversation! I'm really looking forward to their book. Do we have a title yet to search for?
Fascinating discussion. I look forward to reading the book.
I would love to see them in a round table discussion with Dr. Peter Kreeft on St. Thomas.
This was great!!!
Awesome!
Etienne gilson has some great work on st tommy
The guy who printed the first copy of Plato's work?
I don't understand the explanation of the third way here. I take the professor to be saying that if there is a possible world in which nothing exists this means that the actual world could not exist. Why would the possibility of nothing existing imply that nothing could exist in actuality? I'm sure I'm misunderstanding the meaning of possible worlds, but would be great is someone could clear that up.
Here’s my limited understanding: imagine we’re trying to refute this claim: ‘There could exist a possible world where it’s NOT EVEN POSSIBLE for anything to exist (neither necessary or possible beings).’
Well if that world were truly possible, then there could exist no world where there are beings. But there are worlds where beings exist, I.e our world therefore that initial claim is false.
From there I think the argument goes on to claim that all possible beings come into being and therefore need an underlying necessary being to explain how they ultimately come into being. This not a temporal argument but a metaphysical 1 based on how possible beings come into being.
Anyways sure there are better explanations, but this kind of helps for me.
@@markbirmingham6011 thanks but I still don’t get it 😅
I’m having trouble with the following implication: there could exist a world where nothing exists -> there could exist no world where there are beings. I don’t understand how the consequent follows from the antecedent. Why would the mere possibility of nothing existing imply that the actual world couldn’t exist?
As I understand it, the basic idea is that the space of ways that the world might have been doesn't vary with the particular state of the world.
If it were genuinely possible for there to be a nothing-world, a state of affairs where nothing existed ('null-world'), then since such a world would lack any ground for the possibility of anything, nothing would or could in principle exist, given such a world.
However, since the ways that a world might have been in principle don't vary no matter the state of affairs, if things are in-principle impossible in null-world, they are impossible in all realisable states of affairs, including the actual state of affairs. So if null-world is possible, there should not be anything. But there is something, so null-world is not possible.
Since the idea that independent things don't have to exist implies the possibility of null-world, null-world being impossible entails the denial of the thesis that independent things don't have to exist. So there must be independent and necessary beings.
Yeah, it's a bit tricky, but let me try my hand at it:
He's working on the (admittedly somewhat controverted) assumption that possibility and necessity are consistent across possible worlds. This is to say, what is possible/necessary in World1 is also possible/necessary in World2.
Now, let's say we grant that there is a possible world (let's call is World$) where there is nothing at all. Since there is nothing in World$ - nothing to cause or be caused, nothing to change or be changed - then it is a world in which there are no possibilities aside from what is actual in World$ (namely, nothing).
Combine that conclusion with the assumption mentioned above: If, in World$, there are no possibilities beyond World$, then, on the aforementioned assumption that possibility/necessity are consistent across possible worlds, it follows that only World$ is possible. Indeed, perhaps we can say that, necessarily, World$ is the only possible world. But World$ is an empty world, and our world most definitely is not empty. Hence, it is false that World$ is the only possible world. If we modus tollens the whole chain of reasoning back to the beginning, we would conclude that World$ is impossible, and, consequently, there must be some necessary being Who/Which exists in all possible worlds.
To put it another way, they are effectively making a modal collapse argument and using that as a reductio to the assumption that only contingent things exist. To abbreviate the argument, it would basically look like:
1) If only contingent things exist, then World$ is the only possible world.
2) World$ is not the only possible world (on account of our world not looking like World$).
3) Therefore, it is not the case that only contingent things exist.
All that being said, I have questions and reservations about the argument related to S5 modal logic and the issue of whether possible worlds are meant to include the actual world or rather function as a counterfactuals to the actual world. But all that aside, I think the above traces what they are trying to get at.
@@xenophanes4898well done
Comment for traction
Paging Ed Feser
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The first six minutes say nothing. Tempted to move on….
Then move on