Paraconsistent logic

[Andre1000]

Paraconsistent logic is a logic where “Ex falso quodlibet” does not count and contradictions are possible.
Wiki:
en.wikipedia.org/wiki/Paraconsistent_logic

Maybe classical logic does not allow contradictions because we are too stupid to imagine.
Discuss!

 

[Andre1000]

Looks like paraconsistent logic is too academic for people, lol.

 

[Perplexity]

I think these non-classical logics are intriguing formalisms but I don’t think they reflect reality: any argument for dialetheism will rely on premises less obvious than the law of non-contradiction.

 

[empther]

I checked the wikipedia article. It’s full of symbolic logic as all these theories are. You write symbols on paper and you can say anything you want, and become famous as the philosopher who first identified a new theory.

If it can’t be explained in plain English,
it’s garbage.

 

[Just_Lurking]

I like non-monotonic logic better than paraconsistent logic. It matches my experience that the more I learn, the less I know!

en.wikipedia.org/wiki/Non-monotonic_logic

 

[Andre1000]

I checked the wikipedia article. It’s full of symbolic logic as all these theories are. You write symbols on paper and you can say anything you want, and become famous as the philosopher who first identified a new theory.

If it can’t be explained in plain English,
it’s garbage.

Come on this article is easy to understand.

 

[Andre1000]

I like non-monotonic logic better than paraconsistent logic. It matches my experience that the more I learn, the less I know!

en.wikipedia.org/wiki/Non-monotonic_logic

That’s an interesting connection between learning and logic.

 

[Andre1000]

I think these non-classical logics are intriguing formalisms but I don’t think they reflect reality: any argument for dialetheism will rely on premises less obvious than the law of non-contradiction.

But why are contradictions impossible?

 

[Perplexity]

But why are contradictions impossible?

A contradiction is the affirmation of a proposition with its negation: p & ~p. The problem is that on no theory of truth (correspondence, coherence, deflationist etc.) is a contradiction ‘true’, on every theory of truth a contradiction is ‘false’. It’s false by the very truth-conditions of conjunctions: a conjunction is true iff each of its conjuncts are true. This means that its falsity isn’t local to certain possible worlds but extends to all possible worlds. A proposition is defined as impossible if it’s false in every possible world. Therefore, since contradictions are false in every possible world, they’re impossible.

 

[norain]

I’ve never seen this before.

I think what Perplexity just described is the obvious objection to this. Reading the Wikipedia article, I think it is important to figure out in what instances this might apply, not where it cannot, which is the usual (classic?) form of logic.

I also immediately wonder whether apparently true inconsistencies may be broken down into theorems in logic to see where the fallacy lies.