TonesInDeepFreeze

I essentially agree. My point is that: (R v A) -> (~R -> A) R v A therefore ~R -> A is an instance of modus ponens, but (R v A) -> (~R -> A) R v A the...

Make explicit 'Republican' and 'Democrat': 'P' stands for 'Republican wins'. 'D' stands for 'Democrat wins'. Add the background premises: P <-> (R v A...

Yes, but the puzzle (if there truly is one) maintains with or without resort to talking about domains. Include the premises: R ~C ~A Then (R v A) -> (...

Yes, my mistake.

At a point before the election, with 'wins' understood as 'will win', then R v A is true. At a point after the election, with 'wins' understood as 'wo...

We may state these atomic propositions purely as sentence letters so there is not a need to involve domains.

Since R is the case, ~R -> A is true. Bu the puzzle includes an intensional operator "believe'.

'R' for 'Reagan wins' 'A' for 'Anderson wins' 'C' for 'Carter wins' 'R v A' for 'a Republican wins' (R v A) -> (~R -> A) R v A therefore ~R -> A That'...

What are your thoughts on this?: https://thephilosophyforum.com/discussion/comment/565970

Maybe there's a paraconsistent modal logic system, and semantics for it that provide that LNC is true in some models but not in other models?

Too hard trying to find where he made the claim about LNC. That's okay, I guess it doesn't bear on this discussion.

I'll rewrite that in text only ('A' for universal quantifier, 'N' for 'necessarily', 'X' for the existence predicate. Ay N Xy But what do you mean by ...

Since that post, I am reading to find more about the existence predicate (that I would call just 'E' and not 'E!' as others have), but I haven't yet c...

Would you please link to it?

Going back to your first post: I don't know what you mean by that. There is mention of systems and contradiction, which is syntactic, and mention of w...

Right, that was my Task (2). But I mentioned considerations about in my last paragraph. The natural way to do it is first to derive the deduction theo...

I realized that a natural deduction proof of LNC is also trivial. This one has different notation, but it is essentially the same as in Kalish, Montag...

Yes, it's the proof of a theorem about propositional logic. And we prove not just that LNC is true in a particular model but moreover that it is true ...

That might be tedious for me to type out, and if you are not familiar with proof calculi for propositional logic, then it wouldn't be of much use to y...

Yes, I mentioned it as a possibility. It was ungenerous of me to wonder whether you were trolling when Occam's razor would better suggest that you mer...

Logic is about entailment and inference. Logic concerns both syntax of language and meaning with language. Meaning includes denotation, which concerns...

That's a very silly question. I don't know they don't prove it as a theorem, since it is not the case that they don't prove it as a theorem, and I can...

They prove it as a theorem. Of course, our motivation for the system would include proving it as a theorem. "Talk meaningfully" is a large and undefin...

Not all proofs use the law. Indeed, the law is not even usually one of the logical axioms. Yes it can. (Here I'm taking the law in the sense of a sing...

I wish we had a specific formal semantics that together we reference. Otherwise, we risk getting lost in the twists and turns of an analysis bereft of...

You know, like in the movie trailer when the voiceover guy says, "In a world where salamanders are smarter than humans ...", the world is not just the...

Quantified modal logic is pretty technical. And I am rusty in my brief study of it long ago. So I might not state some things correctly, but I'll do m...

So {e b} and {e} are domains. So W1 and W2 are domains. But you say that W1 and W2 are worlds. As far as I can tell, that is conflating 'world' with '...

Would you please tell me in what book or article I can read the stipulation of semantics for quantified modal logic you use? What are W1 and W2? I wou...

You continued to claim that I didn't write 'onto itself'. You even quoted the post where I wrote 'onto itself' and said you do not see it, and yet it ...

I recall the discussion I mentioned. It wasn't about the supposed absence of 'not' (I think perhaps that was another incident) but the bizarrely incor...

Of course not with you. You don't wish to respond to the point that you made a false claim about me: So clearly false that all one has to do is look a...

I didn't mean in this particular argument. Granted, I could have been made it explicit that I recognize that I can be clearer sometimes but that I am ...

Not only do I think it is possible, but I bet it's true. I am keenly aware that (1) It is difficult to write about these topics on-the-fly and in the ...

I am truly curious why you even disputed it to begin with, and then persisted in yet another post. Especially as this is typical with you. You weren't...

No, you regularly ignore and misconstrue, sometimes even to the point of posting as if I said the bald negation of what I actually said. Meanwhile, I ...

The claim that "the set of particles is finite" contradicts the axiom of infinity is shockingly wrong.

What possibly could refute that it is consistent that some sets are finite and other sets are infinite? What I wrote is: You continually ignore and te...

No it does not. If you can't see that, then discussion with you is hopeless. That some sets are finite does not contradict that some sets are infinite...

I'm going to address your question. But I have some other remarks first, and I'll quote from some earlier posts that are important still in the contex...

Yes, I deleted my reply because immediately after posting it, I read about the Euler and Riemann sums.

I didn't say it does. And I am not saying that it would be consistent if it did. I am saying that I haven't seen an argument that it would be inconsis...

I think I might have had an incorrect premise that modal semantics evaluates truth in these stages: first per world and then per model. Rather, perhap...

I see now that I face an obstacle in talking about constant symbols and terms with you. That obstacle is that I am using Hughes & Cresswell, but their...

Right, my mistake, we're talking about modal logic. But make the correct substitution, and my remarks still pertain both to domains for models with pr...

I'm not addressing philosophy of language or more advanced modal logic, but in ordinary predicate logic, 'Donovan' is a plain name (essentially, it's ...

I seem to be again on a different page from you. I'm referring to constant symbols. It is not the case that the point is to have the value for a const...

Sure, but I wonder what it would be. Do you have any thoughts on my question: How can we have a method of models in which, for certain models, there a...

That's not a usage I have happened to have seen. But that doesn't in itself disqualify it. But at least now it is clear that 'E' as a predicate is a v...

That is the ordinary uniqueness quantifier, not a predicate. So, thus far, we have: 'E' as a predicate symbol before a term: where 't' is a term, Et. ...