• Corvus
    3.1k
    Can't wait until you're actually ready to start looking at logic.flannel jesus

    If you can recall, it had been explained repeatedly over and over again.
  • flannel jesus
    1.8k
    Yes, you can explain 2+2 = 5 many many times and still be wrong. Most of your explanations involve saying some nonsense about "logic can't involve content" and other non sequiturs. In other words, non-arguments to prove a Fallacy. Usually followed by a complete unwillingness to investigate your own logic seriously.
  • Corvus
    3.1k
    Yes, you can explain 2+2 = 5 many many times and still be wrong.flannel jesus
    Nope, never said anything like that in this thread. You must be dreaming, or believing that everything in the arguments and explanations were poems.
  • flannel jesus
    1.8k
    Insisting that denying the Antecedent is something you can do because of modus ponens is absolutely like that. You ready to talk about it or what?
  • Corvus
    3.1k
    You seem to have read something about MP on the internet and been parroting about it here until cows come home. You don't seem to know how to apply logic in the real life situations.
  • flannel jesus
    1.8k
    Do you want to just sling shit or do you want to defend your use of modus ponens? I could waste your time talking about how you parrot nonsense until cows come home, or we can talk logic. You ready to stop slinging shit and talk logic?
  • Corvus
    3.1k
    You are back to your old habit of throwing the muck vulgarity again here instead of seeing the point.
  • flannel jesus
    1.8k
    yes, please tell me the point without saying things like

    You seem to have read something about MP on the internet and been parroting about it

    Can you get to the point without slinging shit?
  • Corvus
    3.1k
    Just talk to Banno. I will leave you to it.
  • flannel jesus
    1.8k
    My point is clear, here's my non shit slinging point:

    You cannot logically go straight from p -> q to not p -> not q. If you're in a situation where p implies q, that does NOT mean you're necessarily in a situation where not p implies not q. That's why denying the Antecedent is a formal Fallacy

    Your arguments so far amount to applying that Fallacy
  • Corvus
    3.1k
    I will speak to Banno when he comes back with his replies. But I don't speak to the folks who throws the out of context muck vulgarity in the discussions. All the best.
  • flannel jesus
    1.8k
    wait wait wait, you can be as insulting as you like, but if I say I don't like you slinging shit, I'm at fault because I used a naughty word?

    Dude, just don't sling shit. Naughty words are fine. Unnecessary shit slinging is not. This isn't preschool, people can say naughty words.

    You always find the goofiest ways to cop out of defending your arguments , never a real defense. The latest cop out: my mom told me not to talk to people who say the s word.
  • Corvus
    3.1k
    You are back in my To-Ignore list. Bye~
  • flannel jesus
    1.8k
    if denying the Antecedent were valid, you could just prove it. You want to find these goofy exits to these conversations because you want to maintain your own denial.
  • Fire Ologist
    702
    Descartes says: “You are standing on the train tracks, and that train is coming fast, therefore you are going to get hit!”

    Opponent: “First of all there are the epistemological problems - how can you know any of this? And what is this “train” really or what “you” means?”

    Descartes: “You need to get off the tracks! The train is coming therefore you will get hit or worse!”

    Opponent: “Therefore? Really?? It’s not even a logical statement. I can show you how meaningless your babbling is with some analytics.”

    Descartes: “Ok. Just sayin. You might want to be quick about it. Because I don’t think we are talking about the same thing, and I’d like to get back to my point.”
  • flannel jesus
    1.8k
    is Descartes arguing about something so urgent? It doesn't feel urgent like that to me. I agree with the cogito, but someone like banno saying he isn't certain of it... I don't think banno is making an urgently dangerous error or anything (maybe no error at all). Do you?
  • Fire Ologist
    702

    No, no urgency in the cogito or anti-cogito argument. Just trying to analogize looking at the logic of the words before addressing the meaning of the statement.
  • Banno
    24.8k
    Why do you want to prove (t→e)→(¬t→¬e) is equivalent to A <-> B?Corvus

    I don't, since it isn't. And that was directed at
    I can prove itflannel jesus
  • Banno
    24.8k
    ust trying to analogize looking at the logic of the words before addressing the meaning of the statement.Fire Ologist

    Whaat does that mean - that we need a predicate logic? I offered that already. Have you an analysis that shows the validity of "I think, therefore I am"?

    banno saying he isn't certain of it.flannel jesus
    To be sure, that is not what I am saying; but that certainty of my existence is not dependent on the cogito. Further, I suspect your exist was undoubted long before encountering the Cogito.
  • Corvus
    3.1k
    I don't, since it isn't. And that was directed at
    I can prove it
    — flannel jesus
    Banno

    Fair enough. I got email from the forum that you quoted me in your post, and I also read in your post you saying my logic is wrong in somewhere. So I was trying to clarify on that point.

    There are so many ways to reason about the Cogito statement to prove. You apply several assertions and inferences to the statement to prove. Some will be valid and some invalid. But what we were trying to prove was not validity here. We were trying to prove the statement is true or false, sound or unsound.
  • Banno
    24.8k
    You think you have proved it false, but you apparently use an invalid argument.

    Others here claim that it is true, and indubitable, but offer no support for that contention.

    It would help your standing immensely if you were to explicitly reject the argument that
    (t→e)→(¬t→¬e).
  • flannel jesus
    1.8k
    you'd have to convince him to first. He thinks that's Modus Ponens, and then insults people who look for sources about modus ponens to show that it's not.
  • Fire Ologist
    702
    Have you an analysis that shows the validity of "I think, therefore I am"?Banno

    The “validity?” Of the cogito text? An “analysis”?

    The point of the cogito, once you get the point, is that no analysis is needed; by analyzing anything further, you just make the point again.

    And again.

    If one is carefully considering whatever may exist, once one comes to be considering one’s own existence, one finds something existing that one can’t deny.

    One can deny the statement, but then “I deny, therefore I am.”

    And again..
  • Corvus
    3.1k

    (t→e)→(¬t→¬e)
    (¬t→¬e) = F
    hence (t→e) = F

    Would you agree on that?
    Ignore the MP nonsense. It is not relevant here.
  • Banno
    24.8k
    Whatever. Flogging him repeatedly is tiresome.

    If one is carefully considering whatever may exist, once one comes to be considering one’s own existence, one finds something existing that one can’t deny.Fire Ologist

    Notice the "if...then" in that? If what you say were so, someone ought be able to set the argument out formally.
    If (one is carefully considering whatever may exist) and (one comes to be considering one’s own existence) then (one finds something existing that one can’t deny)

    One can find all sorts of other stuff that one cannot coherently deny - like that you are reading this post. So if that is our standard, the Cogito is hardly special.
  • Corvus
    3.1k
    The “validity?” Of the cogito text? An “analysis”?

    The point of the cogito, once you get the point, is that no analysis is needed; by analyzing anything further, you just make the point again.
    Fire Ologist

    But you see that even a simple logical formalisation and reasoning of Cogito, proves it is false.
  • Banno
    24.8k


    I gather (¬t→¬e) = F is to be understood as "(¬t→¬e) implies the false"?

    No, it doesn't. Countermodel: Rocks don't think, but exist.


    But you see that even a simple logical formalisation and reasoning of Cogito, proves it is false.Corvus
    You have not shown this.
  • Corvus
    3.1k
    The “validity?” Of the cogito text? An “analysis”?Fire Ologist

    Logical validity is only relevant, if Cogito had been deduced from some premises. But it hadn't.
    The only premise of Cogito was Descartes has doubted everything (presumably).
  • Corvus
    3.1k
    I gather (¬t→¬e) = F is to be understood as "(¬t→¬e) implies the false"?

    No, it doesn't. Rocks don't think, but exist.
    Banno

    Therefore (¬t→¬e) = F ?
  • Banno
    24.8k


    I don't know what you are asking. Shouldn't that be (¬t→¬e) → F? Which is not valid, as shown by the countermodel.

    https://www.umsu.de/trees/#(~3t~5~3e)~5(p~1~3p)
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