I really don’t understand what “best explanation”, “true”, or “exist” mean, as stand-alone words divorced from predictions about observations we might ultimately make about them.
Nobody is saying that anything has to be divorced from prediction , in the sense that emperical evidence is ignored: the realist claim is that empirical evidence should be supplemented by other epistemic considerations.
Best explanation:-
I already pointed out that EY is not an instrumentalist. For instance, he supports the MWI over the CI, although they make identical predictions. Why does he do that? For reasons of explanatory simplicity , consilience with the rest of physics, etc
.as he says. That gives you a clue as to what “best explanation” is. (Your bafflement is baffling...it sometimes sounds like you have read the sequences, it sometimes sounds like you haven’t. Of course abduction, parsimony, etc are widely discussed in the mainstream literature as well ).
True:- mental concept corresponds to reality.
Exists:- You can take yourself as existing , and you can regard other putative entieties as existing if they gave some ability to causally interact with you. That’s another baffling one, because you actually use something like that definition in your argument against mathematical realism below.
This isn’t just a semantic point, I think. If there are no observations we can make that ultimately reflect whether something exists in this (seems to me to be) free-floating sense, I don’t understand what it can mean to have evidence for or against such a proposition.
Empirical evidence doesn’t exhaust justification. But you kind of know that, because you mention “good argument” below.
So I don’t understand how I am even supposed to ever justifiably change my mind on this topic, even if I were to accept it as something worth discussing on the object-level.
Apriori necessary truths can be novel and surprising to an agent, in practice, even though they are apriori and necessary in principle… because a realistic agent can’t instantaneously and perfectly correlate their mental contents, and don’t have an oracular list of every theory in their head. You are not a perfect Bayesian. You can notice a contradiction that you haven’t noticed before. You can be informed of a simpler explanation that you hadn’t formulated yourself.
What can possibly sway me one way or another when all variables X that I appear to be able to observe (or think about, etc.) are in the concrete realm, which is defined to be entirely non-intersecting with the Platonic realm?
Huh? I was debating nomic realism. Mathematical realism is another thing. Objectively existing natural laws obviously intersect with concrete observations , because if Gravity worked on an inverse cube law (etc), everything looked very different.
You don’t have to buy into realism about all things, or anti realism about all things. You can pick and choose. I don’t personally believe in Platonic realism about mathematics, for the same reasons you don’t. I believe Nomic realism is another question...its logically possible for physical laws to have been different.
@shminux defined the the thing he is arguing against as “Platonic” .. I don’t have to completely agree with that, nor do you. Maybe it’s just a mistake to think of nomic realism as Platonism. Platonism marries the idea of non-mental existence and the idea of non causality...But they can be treated separately.
What can that possibly mean in this context?”
what context? You’re talking about mathematical realism, I’m talking about nomic realism.
as lines of logic and reasoning, whose validity and soundness implies we are more likely to be in a world where certain possibilities are true rather than others (when mulling over multiple hypotheses
What have I said that makes you think I have departed from that?
@Shminux
If push comes to shove, I would even dispute that “real” is a useful category once we start examining deep ontological claims
Useful for what? If you terminally value uncovering the true nature of reality, as most scientists and philosophers do, you can hardly manage without some concept of “real”. If you only value making predictions, perhaps you don’t need the concept....But then the instrumentalist/realist divide is a difference in values, as I previously said, not a case of one side being wrong and the other side being right.
“Exist” is another emergent concept that is not even close to being binary, but more of a multidimensional spectrum (numbers, fairies and historical figures lie on some of the axes).
“Not a binary” is a different take from “not useful”.
The critical point is that we have no direct access to the underlying reality, so we, as tiny embedded agents, are stuck dealing with the models regardless.
“No direct access to reality” is a different claim to “no access to reality” is a different claim to “there is no reality” is a different to “the concept of reality is not useful”.l
I can provisionally accept that there is something like a universe that “exists”, but, as I said many years ago in another thread, I am much more comfortable with the ontology where it is models all thea way down (and up and sideways and every which way).
It’s incoherent. What are these models, models of?
Nobody is saying that anything has to be divorced from prediction , in the sense that emperical evidence is ignored: the realist claim is that empirical evidence should be supplemented by other epistemic considerations.
Best explanation:- I already pointed out that EY is not an instrumentalist. For instance, he supports the MWI over the CI, although they make identical predictions. Why does he do that? For reasons of explanatory simplicity , consilience with the rest of physics, etc .as he says. That gives you a clue as to what “best explanation” is. (Your bafflement is baffling...it sometimes sounds like you have read the sequences, it sometimes sounds like you haven’t. Of course abduction, parsimony, etc are widely discussed in the mainstream literature as well ).
True:- mental concept corresponds to reality.
Exists:- You can take yourself as existing , and you can regard other putative entieties as existing if they gave some ability to causally interact with you. That’s another baffling one, because you actually use something like that definition in your argument against mathematical realism below.
Empirical evidence doesn’t exhaust justification. But you kind of know that, because you mention “good argument” below.
Apriori necessary truths can be novel and surprising to an agent, in practice, even though they are apriori and necessary in principle… because a realistic agent can’t instantaneously and perfectly correlate their mental contents, and don’t have an oracular list of every theory in their head. You are not a perfect Bayesian. You can notice a contradiction that you haven’t noticed before. You can be informed of a simpler explanation that you hadn’t formulated yourself.
Huh? I was debating nomic realism. Mathematical realism is another thing. Objectively existing natural laws obviously intersect with concrete observations , because if Gravity worked on an inverse cube law (etc), everything looked very different.
You don’t have to buy into realism about all things, or anti realism about all things. You can pick and choose. I don’t personally believe in Platonic realism about mathematics, for the same reasons you don’t. I believe Nomic realism is another question...its logically possible for physical laws to have been different.
@shminux defined the the thing he is arguing against as “Platonic” .. I don’t have to completely agree with that, nor do you. Maybe it’s just a mistake to think of nomic realism as Platonism. Platonism marries the idea of non-mental existence and the idea of non causality...But they can be treated separately.
what context? You’re talking about mathematical realism, I’m talking about nomic realism.
What have I said that makes you think I have departed from that?
@Shminux
Useful for what? If you terminally value uncovering the true nature of reality, as most scientists and philosophers do, you can hardly manage without some concept of “real”. If you only value making predictions, perhaps you don’t need the concept....But then the instrumentalist/realist divide is a difference in values, as I previously said, not a case of one side being wrong and the other side being right.
“Not a binary” is a different take from “not useful”.
“No direct access to reality” is a different claim to “no access to reality” is a different claim to “there is no reality” is a different to “the concept of reality is not useful”.l
It’s incoherent. What are these models, models of?