Thanks for writing up an excellent Reduction Ad Absurdum of verificationism. As they say, “One man’s modus ponens is another man’s modus tollens”.
I strongly agree with the claim that it is self-defeating. Here’s another weird effect—let’s suppose I roll a dice and see that it is a 6. I then erase the information from my brain, which then takes us to a position where the statement is impossible to verify. Does the statement then become meaningless?
Beyond this, I would say that “exists” is a primitive. If it makes sense to take anything as a primitive, then it makes sense to take “exists” as a primitive. And the thing with primitives is that you can’t really define them in any satisfactory sense. Instead, you can only talk around them.
It’s only self-defeating if you aren’t careful about definitions. Which admittedly, I haven’t been here. I’m writing a blog post exploring a topic, not an academic paper. I’d be glad to expand a bit more if you would point to a specific self-defeater.
>Here’s another weird effect—let’s suppose I roll a dice and see that it is a 6. I then erase the information from my brain, which then takes us to a position where the statement is impossible to verify. Does the statement then become meaningless?
Yes, it’s irrelevant to any future predictions.
Re exist being primitive: it’s a weird primitive that
1. Is entirely useless for any kind of prediction
2. Is entirely impossible to obtain evidence about even in theory
3. Appears to break down given plausible assumptions about the mere possibility of a multiverse
If anything, I think “exist is a primitive” is self-defeating, given 3. And it’s useless for purposes people tend to use it for, given 1 and 2.
Do you think there’s a “fact of the matter” as to which branch of the level III multiverse we’re in? What about levels I, II, and IV?
Just because it is convenient to use exists in a way that refers to a particular scope of a multiverse, doesn’t prevent us as treating the whole multiverse as just a rather unusual universal and using the term exists normally. But aren’t claims about a multiverse inconsistent with your strong verificationism?
>I didn’t mention a specific self-defeater as that’s been discussed in the comments above.
I’ve responded to each comment, Which argument do you think has not been sufficiently responded to?
>1. Denying the existence of a deeper, unobservable reality or saying that speaking about it is nonsense is also useless for any kind of prediction
You’re the one saying we should treat this notion as primitive. I’m not arguing for taking verificationism as an axiom, but as a considered and argued for conclusion. You obviously need far stronger arguments for your axioms/primitives than your argued conclusions.
>2. The Universe Doesn’t Have to Play Nice
It seems like there’s a great deal of agreement in that post. You concede that there’s no way to obtain evidence against Boltzmann or any knowledge about realism, agreeing with my 1 and 2 above (which are controversial in philosophy.) I don’t see what part of that post has an objection to the kind of reasoning here. I’m not saying the universe must play nice, I’m saying it’s odd to assert a primitive under these conditions.
>Just because it is convenient to use exists in a way that refers to a particular scope of a multiverse, doesn’t prevent us as treating the whole multiverse as just a rather unusual universal and using the term exists normally.
This would be consistent with my argument here, which is about claims that are true in some parts of the multiverse and false in others. If you retreat to the viewpoint that only statements about the multiverse can use the term exist, then you should still agree that statements like “chairs exist in our world” are meaningless.
>aren’t claims about a multiverse inconsistent with your strong verificationism?
I think I live in a level IV multiverse, and the sense I mean this in is that my probability expectations are drawn from that multiverse conditioned on my current experience. It’s entirely a statement about my expectations. (I also have a small probability mass on there being branches outside level IV with uncomputable universes, such as ones containing halting oracles.) I think this is meaningful but “the level IV multiverse actually exists” is not.
Thanks for writing up an excellent Reduction Ad Absurdum of verificationism. As they say, “One man’s modus ponens is another man’s modus tollens”.
I strongly agree with the claim that it is self-defeating. Here’s another weird effect—let’s suppose I roll a dice and see that it is a 6. I then erase the information from my brain, which then takes us to a position where the statement is impossible to verify. Does the statement then become meaningless?
Beyond this, I would say that “exists” is a primitive. If it makes sense to take anything as a primitive, then it makes sense to take “exists” as a primitive. And the thing with primitives is that you can’t really define them in any satisfactory sense. Instead, you can only talk around them.
It’s only self-defeating if you aren’t careful about definitions. Which admittedly, I haven’t been here. I’m writing a blog post exploring a topic, not an academic paper. I’d be glad to expand a bit more if you would point to a specific self-defeater.
>Here’s another weird effect—let’s suppose I roll a dice and see that it is a 6. I then erase the information from my brain, which then takes us to a position where the statement is impossible to verify. Does the statement then become meaningless?
Yes, it’s irrelevant to any future predictions.
Re exist being primitive: it’s a weird primitive that
1. Is entirely useless for any kind of prediction
2. Is entirely impossible to obtain evidence about even in theory
3. Appears to break down given plausible assumptions about the mere possibility of a multiverse
If anything, I think “exist is a primitive” is self-defeating, given 3. And it’s useless for purposes people tend to use it for, given 1 and 2.
Do you think there’s a “fact of the matter” as to which branch of the level III multiverse we’re in? What about levels I, II, and IV?
I didn’t mention a specific self-defeater as that’s been discussed in the comments above.
Denying the existence of a deeper, unobservable reality or saying that speaking about it is nonsense is also useless for any kind of prediction
The Universe Doesn’t Have to Play Nice captures my objections to this kind of reasoning
Just because it is convenient to use exists in a way that refers to a particular scope of a multiverse, doesn’t prevent us as treating the whole multiverse as just a rather unusual universal and using the term exists normally. But aren’t claims about a multiverse inconsistent with your strong verificationism?
>I didn’t mention a specific self-defeater as that’s been discussed in the comments above.
I’ve responded to each comment, Which argument do you think has not been sufficiently responded to?
>1. Denying the existence of a deeper, unobservable reality or saying that speaking about it is nonsense is also useless for any kind of prediction
You’re the one saying we should treat this notion as primitive. I’m not arguing for taking verificationism as an axiom, but as a considered and argued for conclusion. You obviously need far stronger arguments for your axioms/primitives than your argued conclusions.
>2. The Universe Doesn’t Have to Play Nice
It seems like there’s a great deal of agreement in that post. You concede that there’s no way to obtain evidence against Boltzmann or any knowledge about realism, agreeing with my 1 and 2 above (which are controversial in philosophy.) I don’t see what part of that post has an objection to the kind of reasoning here. I’m not saying the universe must play nice, I’m saying it’s odd to assert a primitive under these conditions.
>Just because it is convenient to use exists in a way that refers to a particular scope of a multiverse, doesn’t prevent us as treating the whole multiverse as just a rather unusual universal and using the term exists normally.
This would be consistent with my argument here, which is about claims that are true in some parts of the multiverse and false in others. If you retreat to the viewpoint that only statements about the multiverse can use the term exist, then you should still agree that statements like “chairs exist in our world” are meaningless.
>aren’t claims about a multiverse inconsistent with your strong verificationism?
I think I live in a level IV multiverse, and the sense I mean this in is that my probability expectations are drawn from that multiverse conditioned on my current experience. It’s entirely a statement about my expectations. (I also have a small probability mass on there being branches outside level IV with uncomputable universes, such as ones containing halting oracles.) I think this is meaningful but “the level IV multiverse actually exists” is not.