Posted: Nov 09, 2018 9:04 pm
Right, but you didn't. You said it was true, then went back and revised and qualified that statement when it proved inadedquate, which is exactly the kind of problem with his dichotomy.
I hasten to add that this isn't really criticism, it's the only practical way to deal with these things if you don't want to be insufferably pedantic, and I would also go back and qualify if it became necessary.
Thomas Eshuis wrote:So either the dichotomy is Donald Trump Jr. is or is not the son of Donald Trump Sr.
or
Donald Trump Sr. is or is not the son of Donald Trump Sr.Thommo wrote:
3) was going to be:
3) "Donald Trump is the president of the United States of America and Donald Trump is the son of Donald Trump" means the same as "Donald Trump is the president of the United States of America and he is the son of Donald Trump".
In fairness I'm fresher this morning and I could probably just have used the liar sentence:
"This sentence is false" and asked if it's true or false, anyway.
I think you would agree that it cannot be both true and false at the same time though, right?
It depends. You can variously say it's both, neither or undefined. There are different approaches in the study of logic.
The single approach that does not work is that you HAVE to say it's true or false, which is Matt's assertion. This also applies to gibberish (another example he gave) - in formal logic you only map what are know as "well formed formulae" or "wff"s to truth values, the same is probably wise in English.
From the other side there are all sorts of examples as well where although you think of something as being "correct" or "true" you can't actually prove it true or not true.
Further, various precise treatments of logic which don't respect Matt's dichotomy can be found in rigorous areas like fuzzy logics and multivalent logics.
Thomas Eshuis wrote:Thommo wrote:A more practical example would be to ask why fact checking sites use scales with assessments like "mostly true" or "mostly false". Hopefully this will communicate some of the problems I was alluding to!
It does and I agree that depending on the claim made, there might be gradations of truth. But when we're talking about X existing, I don't see how you can have gradations of truth. Either X exists or it doesn't, right?
Well, within classical logics, that is the case, and by convention people often use those. But logics, like scientific theories are just models, so what's true in the model isn't necessarily true of the world we inhabit. That's the realm of metaphysics.
Matt did ask a good question, which was something like "if it's not true or false, then what else is it?". That's good enough for both formal situations and informal ones. In informal situations equivocation is a genuine risk, and that's why the strictly binary "true or false" approach can go wrong. English is not a complete and consistent logic, it's a language which allows contradiction, insisting that things are always either "A or not A" is a pretty obvious example of black or white thinking. We tend to talk that way due to convention and definition. If you want to see how you can run into problems with this I'm sure you could watch Dillahunty talk about his response to TAG (transcendental argument for god), on his show, which I know he has. I'm sure you'll see that in fact he says these things are not in fact features of the universe.