If it's partly true and partly false, and if false isn't true, then it's partly true and partly not true. — Michael
"Partly" implies division such that true and not true are not said of the same thing, they are said of different parts, the parts being different parts of the same thing. — Metaphysician Undercover
The whole is divided potentially, not actually. So to assume that the whole actually is parts is a category mistake. — Metaphysician Undercover
intuitionists generally uphold bivalence, but they reject excluded middle. — Nagase
He does uphold tertium non datur — Srap Tasmaner
LEM on the other hand doesn't restrict possible truth values. Rather it simply states: for a given propsition P, either P is true or ~P is true. — TheMadFool
When someone says ''it is raining'' is partly true it doesn't mean raining is decomposed into parts. All it means there's another possibility in truth viz. partly true. — TheMadFool
All it means there's another possibility in truth viz. partly true. — TheMadFool
The point I made above is that we must state what we are referring to either the whole, or the parts, because it is contradictory to refer to the whole as parts. — Metaphysician Undercover
If there is another possibility, like this, then you deny the LEM — Metaphysician Undercover
Here's an easier example than fuzzy logic. Suppose some statements are true (T), some statements are false (F), and some statements are both true and false (B, also called a truth-value glut)---so bivalence does not work — Nagase
What I don't see it's contradictory to talk of the whole as parts? Take a chair. I may talk of its seat, its back or its legs without any contradiction. — TheMadFool
No, another possibility of truth value doesn't brrak the LEM. LEM simply puts a restriction on a specific combination of truth values viz. P & ~P. — TheMadFool
If you're talking about the seat, you are talking about "the seat", and not "the chair". If you are talking about "the back" you are talking about "the back", not "the chair". Once you divide the chair into parts, such that you are now referring to "the back", or "the seat", or "the legs", each referring to different identified objects, and not "the chair" as a whole, it is contradictory to claim that you are talking about "the chair" when you are referring to "the back"or any one of the other parts. You are not talking about the chair, you are talking about a specific part of the chair. — Metaphysician Undercover
You are not talking about the chair, you are talking about a specific part of the chair. — Metaphysician Undercover
No, LEM explicitly states that there is not any other possibility. It states that of any subject we can predicate either P or ~P, and there is no other possibility. If you insist that there is another possibility of truth value, you break LEM. — Metaphysician Undercover
If the upholstery of your chair is ugly, doesn't that make the chair ugly? — Srap Tasmaner
Ok. Where's the contradiction? — TheMadFool
I think the PB and LEM are poorly worded - they sound very similar. I'm confused too - that's why the post. — TheMadFool
This is a deductive conclusion which requires the further premise that if the upholstery of a thing is ugly, then so is the thing. Otherwise you have a fallacy of composition — Metaphysician Undercover
A leg is not a chair. — Metaphysician Undercover
If I understand the Wikipedia article correctly, exception to PB is a claim of exception to the law of non-contradiction, instead of claiming exception to the law of excluded middle. So to violate PB is to claim "both P and ~P", whereas an exception to the law of excluded middle would claim "neither P nor ~P". — Metaphysician Undercover
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