Conversion, Obversion, and Contraposition (Categorical Logic)

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  • Опубліковано 23 січ 2025

КОМЕНТАРІ • 45

  • @KonnerGooch
    @KonnerGooch 11 місяців тому +4

    This video was much more helpful than the way the in-class teacher described this lesson.

  • @davidamat6588
    @davidamat6588 3 роки тому +6

    Your explanations are extremely clear. You should keep on doing these videos. Thanks!!

  • @Sorya-gf7qw
    @Sorya-gf7qw 4 роки тому +10

    0:50 I think conversion of A is wrong . If all A are B then it's not necessary that all B are A . I think It's more accurate to say " Some B are A ".

    • @JPWeir
      @JPWeir 3 роки тому +5

      yeah that's true it's a fallacy. Illicit conversion of A

    • @rust5427
      @rust5427 Рік тому

      That's true, I was shocked when I got a wrong mark when I converted "Asians are filipinos" to "some filipinos are asians".
      The correct answer is "Asians are filipinos" like how does a subset(filipino) envelop the whole set(asian)?
      Like, that does not preserve the same meaning as the statement before

  • @riyatanwar2159
    @riyatanwar2159 4 роки тому +33

    Conversion of A is "some B are A" and the conversion of O is not possible

    • @ramyasharma2847
      @ramyasharma2847 10 місяців тому

      If you can please tell why O cannot have a valid conversion would be helpful, since
      Some P are not S seems logical for some S are not P.
      e.g. some boys are not poets -> some poets are not boys
      Is also similar?

    • @domt1
      @domt1 9 місяців тому

      @@ramyasharma2847from the fact that some animal is not a dog, it does not follow that some dog is not an animal

  • @arcanetrace661
    @arcanetrace661 2 роки тому +6

    All of this is clearly explained but forgot to mention that there are two types of conversion
    Simple conversion and partial conversion
    In simple conversion only particular affirmativ (i) and universal negative (E) proposition are valid
    A and O proposition cannot be converted in simple conversion
    in PARTIAL CONVERSION
    this can only be applied to A and E propositions
    The rules in partial conversion
    is the quality of the convertend is reduced from universal to particular
    A is to (i)
    E is to (O)

  • @jaysonrayabellar325
    @jaysonrayabellar325 3 роки тому +2

    thank you for this!!! it helped me in my online classes

  • @rishika6456
    @rishika6456 3 роки тому

    Thanku sir for such a great teaching 🥰 May God Bless you

  • @shade767
    @shade767 2 роки тому +3

    A - Some B are A
    E - No B are A
    I - Some B are A
    O - (Not Convertible)

  • @t1lt69faceitclips3
    @t1lt69faceitclips3 3 роки тому +1

    omfg u just saved me in the obe thanks

  • @kuldipdhiman
    @kuldipdhiman Рік тому

    Thank you very much for clearly explaining them.

  • @WaseemAhmad-bf2mw
    @WaseemAhmad-bf2mw 4 роки тому +5

    Conversion can't be applied for A

    • @davidamat6588
      @davidamat6588 3 роки тому +2

      Did you watch the whole video? He clearly says that Conversion is valid only for E and I, and that Contraposition is only valid for A and O. Check 11:51

  • @CrimsonDevil_Rias
    @CrimsonDevil_Rias Рік тому +1

    Coming from a mathematical standpoint, inversion also works on E-type and I-type statements
    Inversion works in the following way
    Take the regular statements/claims and just term-complement both in the statement
    For example:
    A-type inversion: All A are B → All non-A are non-B
    E-type inversion: No A are B → No non-A are non-B
    I-type inversion: Some A are B → Some non-A are non-B
    O-type inversion: Some A are not B → Some non-A are not non-B
    If you replace A and B with some example terms, say A is dogs and B is cats, then it actually makes intuitive sense for E-type and I-type statements
    No dogs are cats, no non-dogs are non-cats (which by double negating the first term means All dogs are not cats)
    Some dogs are cats, some non-dogs are non-cats (You can take this to mean Some animals that are not dogs are also not cats)
    And like Conversion, there's no guarantee that the truth value for the inversion of an A and O statement will be the same.

    • @philologick6175
      @philologick6175  Рік тому

      Thanks for the comment!
      Unfortunately, this inference would be invalid for E- and I-type statements as well. This can be proven through the use of Venn diagrams (which I hope to make a video about in the future). For now, though, we can stick to coming up with counterexamples.
      Let's say, for "No A are B," that A stands for "dogs" and B for "cats" such that the statement is "No dogs are cats." The statement "No nondogs are noncats" wouldn't follow. This can be tricky to see because of the complements, but I think it's a bit clearer if we rephrase it as such: "There are no things that are not dogs that are also things that are not cats." But there are plenty of such things. For instance, my washing machine is a nondog that is a noncat. The "no nondogs" bit can't be double negated because the "no" just serves as a universal quantifier indicating the relationship between both categories - it isn't serving to negate the complement.
      As for I-type statements, this one threw me for a loop! That's because I found it impossible to think of any categories for which "Some non-A are non-B" would be false. There might be an example that I'm just not creative enough to think of. But even here we can prove with the use of Venn diagrams that the inference would be invalid. Even without, if inversion is defined as just swapping each term with its complement, then it should be equally possible to get from "Some non-A are non-B" to "Some A are B," and here we can easily find counterexamples. Consider: "Some nonparrots are nontrees." This is true, some things that aren't parrots are things that aren't trees. If we grab each term's respective complement, we get "Some parrots are trees," which serves as a counterexample.

  • @trishagrabert6391
    @trishagrabert6391 3 роки тому

    Thank you very much for teaching me this today!

  • @rovoclash4099
    @rovoclash4099 2 роки тому

    Thank you for the explanation.. very much helpfull ...

  • @natalychavez3916
    @natalychavez3916 4 роки тому +1

    Thank you this was extremely helpful!!

  • @levinahakinyi6040
    @levinahakinyi6040 3 роки тому

    U made my work easier thanks

  • @Shreyaa20
    @Shreyaa20 4 роки тому +1

    Very well explained

  • @suruthilenin829
    @suruthilenin829 3 роки тому +1

    WOW. This is sooo useful

  • @DivineDivine-p8z
    @DivineDivine-p8z Рік тому

    Great video

  • @NeddyTheNoodle
    @NeddyTheNoodle 3 роки тому

    Thanks Philologick! :)

  • @martinluckyraj
    @martinluckyraj 3 роки тому

    Thanks for wonderful explanation

  • @pratyushsharma129
    @pratyushsharma129 3 роки тому +4

    You are teaching it wrong. For A, some B are A would be right conversion. Conversion for O is not possible.

    • @nicothomas3484
      @nicothomas3484 5 місяців тому

      It is possible, but it‘s just not valid

  • @alfredhardev
    @alfredhardev Місяць тому

    Inversion?

  • @jahzeellariosa6412
    @jahzeellariosa6412 2 роки тому

    My prof's lecture for 3 hours explained in 13 minutes bruuhhhh

  • @praptibawse6698
    @praptibawse6698 Рік тому

    Thanka a lot for this vid✨🙏

  • @_SINGULAR__
    @_SINGULAR__ 10 місяців тому

    Conversion of O type propositions while possible is invalid

  • @RoqueFernandes-i1k
    @RoqueFernandes-i1k 6 місяців тому

    Contraposition of I is not valid and contraposition of E would be 'some non-B are not non-A'

  • @destinymartin8500
    @destinymartin8500 3 роки тому +1

    THANK YOU BRO

  • @kiahholman2315
    @kiahholman2315 Рік тому

    The I contraposition doesn’t exist, the A + O converse doesn’t exist

  • @joeking4414
    @joeking4414 Рік тому

    O propositions never converts validly and A propositions convert accidentally and not simply like I & E. I came here because I was confused and needed help after bombing my last quiz and the first 30 seconds the video is wrong... thanks I'm now more stressed.

  • @manhalrahman5785
    @manhalrahman5785 2 роки тому

    Thank you

  • @NightOwlGamingz
    @NightOwlGamingz 2 роки тому

    9:10

  • @kashifshah1731
    @kashifshah1731 3 роки тому

    You did conversion wrong.

  • @Zen-lz1hc
    @Zen-lz1hc 2 роки тому

    Like thank you

  • @idioticbeatzz
    @idioticbeatzz 2 роки тому

    You’re wrong about conversion

  • @AA-sn9lz
    @AA-sn9lz 2 роки тому

    This is all wrong. You're changing truth values of the sentences which is a big NO NO

  • @RoqueFernandes-i1k
    @RoqueFernandes-i1k 6 місяців тому

    Contraposition of I is not valid and contraposition of E would be 'some non-B are not non-A'