Actual Proof 1+1=2

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  • เผยแพร่เมื่อ 29 ก.ย. 2024
  • Become a Math Master With My Intro To Proofs Course! (FREE ON TH-cam)
    • Intro To Math Proofs (...
    This video presents a clear and concise proof of why 1+1 equals 2, a fundamental concept in mathematics. It breaks down the logic and reasoning behind this basic equation, making it understandable for anyone interested in math.
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    Disclaimer: This video is for entertainment purposes only and should not be considered academic. Though all information is provided in good faith, no warranty of any kind, expressed or implied, is made with regards to the accuracy, validity, reliability, consistency, adequacy, or completeness of this information. Viewers should always verify the information provided in this video by consulting other reliable sources.

ความคิดเห็น • 563

  • @BriTheMathGuy
    @BriTheMathGuy  7 หลายเดือนก่อน +66

    🎓Become a Math Master With My Intro To Proofs Course! (FREE ON TH-cam)
    th-cam.com/video/3czgfHULZCs/w-d-xo.html

    • @Ostup_Burtik
      @Ostup_Burtik 7 หลายเดือนก่อน

      First

    • @cloverisfan818
      @cloverisfan818 7 หลายเดือนก่อน

      Actually we can prove 1+1=2 by proving lim x->1 x+1=2, using delta epsilon

    • @krzysztofszczepanik8380
      @krzysztofszczepanik8380 7 หลายเดือนก่อน +1

      You used addition in your definition of addition

    • @GEMSofGOD_com
      @GEMSofGOD_com 7 หลายเดือนก่อน

      And a bit more in, a giga condensed form, on my website

    • @India_Pakistan1
      @India_Pakistan1 7 หลายเดือนก่อน

      ​@@krzysztofszczepanik8380true

  • @maxhagenauer24
    @maxhagenauer24 7 หลายเดือนก่อน +976

    That hit hard when he said "If you really want to up your math game..." at the end of the video where he explains why 1 + 1 = 2.

    • @samueldeandrade8535
      @samueldeandrade8535 7 หลายเดือนก่อน

      What do you mean? Are you being ironic? I hope so, because this Bri, so called "The Math Guy", is the most intellectually dish0n3st math youtuber out there.

    • @GEMSofGOD_com
      @GEMSofGOD_com 7 หลายเดือนก่อน +5

      Bri's Mozart!

    • @samueldeandrade8535
      @samueldeandrade8535 7 หลายเดือนก่อน +3

      Hit hard? Because is s1lly af, right?

  • @weo9473
    @weo9473 7 หลายเดือนก่อน +268

    Meanwhile john hush proving 1=2 in every single way possible 🗿

    • @ilmionomenonloso
      @ilmionomenonloso 7 หลายเดือนก่อน +4

      That looks like a rather immediate task: there are no such ways

    • @ayuballena8217
      @ayuballena8217 5 หลายเดือนก่อน +22

      @@ilmionomenonlosothey’re all division by 0

    • @tri99er_
      @tri99er_ 4 หลายเดือนก่อน +5

      @@ayuballena8217 of course they are…

    • @ayuballena8217
      @ayuballena8217 4 หลายเดือนก่อน

      @@tri99er_ exept…

    • @midahe5548
      @midahe5548 12 วันที่ผ่านมา +1

      @@ayuballena8217 except if we assume that every solid in 3 (or more) dimentions are mesureable :)

  • @кирофф
    @кирофф 17 วันที่ผ่านมา +6

    0:20 at this point the 2 circles and the loading icon came together perfectly lol
    upd: maybe only in my phone

  • @Peacemaker8D
    @Peacemaker8D 7 หลายเดือนก่อน +18

    Can you explain the set theory behind the definition of addition?

    • @zemm9003
      @zemm9003 หลายเดือนก่อน +1

      You can define the successor of a set by adding {set} to it. So you have a set X that represents some number in Arithmetic. The successor will be {X, {X}} where {X} is the only set whose unique member is the set X and X and {X} cannot be equal by the foundation axiom of Set Theory.

  • @Dinuga2010
    @Dinuga2010 13 วันที่ผ่านมา +1

    Imagine writing this all down while solving a complicated math problem.

  • @jadengames.3662
    @jadengames.3662 4 หลายเดือนก่อน +1

    It's funny it's actually common sense if you think about it. Another way we could write the equation is more expansive. A=N B=M and C=B-1. Then writing A+B=1+(A+(B-1)) that plus one moves a few spots but if you can sub S for one you will always get that the left and right sides are equal.
    I should clarify it is simplistic the way you explain it however it is still a strange concept if not approached right.

  • @fatfurry
    @fatfurry 7 หลายเดือนก่อน +12

    How and why are you using the + in the definition of +? S(a + c) includes a + but it is in the definition of +

    • @fatfurry
      @fatfurry 7 หลายเดือนก่อน +1

      Do you just need recursion?

    • @ViktorLoR_Mainu
      @ViktorLoR_Mainu 6 หลายเดือนก่อน +12

      @@fatfurry Yeah, you use recursion until you have a + S(0)

    • @mcr9822
      @mcr9822 3 หลายเดือนก่อน

      @@ViktorLoR_MainuDo you just need recursion?

    • @ianmccurdy1223
      @ianmccurdy1223 12 วันที่ผ่านมา

      @@mcr9822 Yes, you use recursion until you have a + S(0)

    • @Random-ly1kg
      @Random-ly1kg 12 วันที่ผ่านมา

      ​@@ianmccurdy1223 Do you just need recursion?

  • @theencryptedpartition4633
    @theencryptedpartition4633 7 หลายเดือนก่อน +2

    This is some terrance Howard level stuff

  • @user-tk2jy8xr8b
    @user-tk2jy8xr8b 22 วันที่ผ่านมา

    Nat = Z : Nat | S : Nat -> Nat
    1. a + Z = a
    2. a + S(b) = S(a + b)
    S(Z) + S(Z) =[#2]=> S(S(Z) + Z) =[congruence #1 over S]=> S(S(Z)) Q.E.D.

  • @ApplePieGuy79
    @ApplePieGuy79 5 วันที่ผ่านมา

    Actually its a window if you combine it all

  • @johanneseloff6219
    @johanneseloff6219 15 วันที่ผ่านมา +2

    most life-changing moment in my life.

    • @ninja4O5
      @ninja4O5 14 วันที่ผ่านมา +1

      Same

  • @Gordy-io8sb
    @Gordy-io8sb 5 หลายเดือนก่อน

    What about fields? 1+1 = 0 in a field of characteristic 2, or, 1+1 = 0 (mod 2).

  • @ayuballena8217
    @ayuballena8217 หลายเดือนก่อน +2

    1+1=10

  • @TopRob1
    @TopRob1 7 หลายเดือนก่อน +3

    I'm not sure if S(1+0) is equal to S(1), I need proof

    • @darthnihilus9342
      @darthnihilus9342 7 หลายเดือนก่อน +2

      He showed that, by definition, a+0 = a

    • @GabriTell
      @GabriTell 7 หลายเดือนก่อน +1

      We know by definition that "x+0=x" for an arbitrary "x".
      So, we have that "1+0=1" is true, and by definition of "=" we have that given an arbitrary property "φ", then "φ[1+0] φ[1]" is tautology.
      So, particularizing "φ[x]" as "1+1=S(x)" for an arbitrary "x", as he's already proven in the video that "φ[1+0]" is true, by modus ponens we have "φ[1]" is true, and therefore "1+1=S(1)" is true.
      So, by transitivity and symmetry law, we have: "x=y" and "y=z" implies "x=z", and "x=y" implies "y=x" for "x", "y" and "z" arbitrary. Therefore, as we have "1+1=S(1+0)" implies "S(1+0)=1+1" and "1+1=S(1)" is true (as we've already proven), we conclude that "S(1+0)=S(1)". □

    • @ssaamil
      @ssaamil 7 หลายเดือนก่อน

      ​@@GabriTellNicely done!

    • @samueljehanno
      @samueljehanno 7 หลายเดือนก่อน

      ​@@GabriTellNicely done

    • @user-tk2jy8xr8b
      @user-tk2jy8xr8b 21 วันที่ผ่านมา

      Easy, S(S(0)+0) =[congruence of a+0=a over S]=> S(S(0))

  • @mowzaw
    @mowzaw 3 หลายเดือนก่อน +1

    1️+1️=11

    • @clintsweetwater
      @clintsweetwater 5 วันที่ผ่านมา

      Finally… the correct answer 🤪

  • @troxexlot18
    @troxexlot18 7 หลายเดือนก่อน

    Proof by definition

  • @SurendraSandun-y1y
    @SurendraSandun-y1y 23 วันที่ผ่านมา

    Okay but how a + b = a when b = 0? Do we need a proof for that

  • @jabi3616
    @jabi3616 21 วันที่ผ่านมา

    apple+ apple= 2 apples
    change my mind!!

  • @DanKaschel
    @DanKaschel 11 วันที่ผ่านมา

    I think its sad, not that so many people didn't understand this excellent video, but that so many people in their pride and anti-academic hubris are here mocking in the comments something which they failed to understand with an undeserved sense of superiority.
    Humility is as necessary for learning as intelligence and probably more so.

    • @almabatekert_villanykorte3387
      @almabatekert_villanykorte3387 7 ชั่วโมงที่ผ่านมา

      Making jokes doesn's necessarily mean mocking

    • @DanKaschel
      @DanKaschel 6 ชั่วโมงที่ผ่านมา

      @@almabatekert_villanykorte3387 Obviously.

  • @schobihh2703
    @schobihh2703 7 หลายเดือนก่อน +1

    I am not sure that you really proved it. You defined a "+" operator through the successor. Therefore you show that 1+1 defined that way is 2. But I think you would still need to show that the way you defined "+" all the other laws like commutativity and associativity still are valid for your "+" operator.

  • @rodhimustofaanshori4444
    @rodhimustofaanshori4444 5 หลายเดือนก่อน

    1️⃣ Adalah salah satunya dengan cara yang paling
    Semuanya Berapa

  • @GlorifiedTruth
    @GlorifiedTruth 7 หลายเดือนก่อน +1936

    I have spent the last 40 years of my life trying to disprove this postulate. I graciously accept defeat at your hands, sir. SIGH.

    • @alien3200
      @alien3200 7 หลายเดือนก่อน +47

      You just wasted 40 years of your life, doing nothing 😊

    • @LeoV6502
      @LeoV6502 7 หลายเดือนก่อน +110

      0(1+1)=0(2+1)
      Cancel the zeros out!

    • @justsaadunoyeah1234
      @justsaadunoyeah1234 7 หลายเดือนก่อน +87

      @@LeoV6502 Illegal! I shall report you to the Math Police!

    • @yesImbob
      @yesImbob 7 หลายเดือนก่อน +32

      @@LeoV6502uhhh that’s not how it works

    • @LeoV6502
      @LeoV6502 7 หลายเดือนก่อน +6

      Mua ha ha ha ha haaah!!!

  • @nikolavulic-t9x
    @nikolavulic-t9x 3 หลายเดือนก่อน +228

    This is what the teacher expects you to do when they say "show your work"

    • @throughthoroughthought8064
      @throughthoroughthought8064 18 วันที่ผ่านมา +8

      I always enjoyed randomly inserting the phrase "and then a miracle occurred here..."

    • @nikolavulic-t9x
      @nikolavulic-t9x 17 วันที่ผ่านมา +4

      ​@@throughthoroughthought8064 lmao, i always did 90% of the stuff in my head, not even on tests just in schoolwork and the teacher would conplain

    • @Allyfyn
      @Allyfyn 14 วันที่ผ่านมา +3

      No, it's really not hard at all.

    • @taco6444
      @taco6444 3 วันที่ผ่านมา +2

      It was revealed to me in a dream

    • @amongusmappingAUM
      @amongusmappingAUM 23 ชั่วโมงที่ผ่านมา

      @@Allyfyn This comment was obviously a joke, in case you didn’t know that.

  • @RayTheomo
    @RayTheomo 10 วันที่ผ่านมา +43

    we got proof that 1+1=2 before gta 6

    • @bjb1016
      @bjb1016 10 วันที่ผ่านมา +1

      💀

  • @gheffz
    @gheffz 7 หลายเดือนก่อน +184

    This "logic" proof could be written in a computer language called Prolog:
    _% Base case: Adding 0 to any number N results in N._
    plus(0, N, N).
    _% Recursive case: To add A and the successor of B, we first add A and B, then find the successor of the result._
    plus(s(A), B, s(C)) :- plus(A, B, C).
    ?- plus(s(0), s(0), s(s(0))).

    • @decaydjk8922
      @decaydjk8922 7 หลายเดือนก่อน +16

      And that is basically how arithmetic is defined in logic programming

    • @mskiptr
      @mskiptr 6 หลายเดือนก่อน +12

      And here's a similar thing but for the programming language and proof assistant, Idris:
      data Nat : Type where
      Z : Nat
      S : Nat -> Nat
      one, two : Nat
      one = S Z
      two = S one
      plus : (a : Nat) -> (b : Nat) -> Nat
      plus a Z = a
      plus a (S b') = S (plus a b')
      data Equals : (a : ty) -> (b : ty) -> Type where
      EqualityIsReflexive : (x : ty) -> Equals x x
      theProof : Equals (plus one one) two
      theProof = EqualityIsReflexive two
      This doesn't need any sophisticated reasoning because `plus one one` simply evaluates to `S (S Z)` and so is already the same thing. The type | proof checker can verify it mechanically.
      Also, if I were to use the standard library just these two lines would do the trick:
      theProof : 1 + 1 = 2
      theProof = Refl

    • @gheffz
      @gheffz 6 หลายเดือนก่อน

      @@mskiptr Excellent. Yes. Question Idris or Agda?

    • @mskiptr
      @mskiptr 6 หลายเดือนก่อน +1

      @@gheffz To be honest I don't have much opinion on Agda because I haven't really tried it (yet). It seems to have a bit more active community around it and I would guess the tooling should be less janky. Also, from what I've seen it's more focused on maths while I'm overall more interested in applying type theory to CS concepts. Oh, and then there are the fancy symbols used everywhere. I kinda like the idea but it has a massive potential to be really annoying and ugly.

    • @user-tk2jy8xr8b
      @user-tk2jy8xr8b 22 วันที่ผ่านมา +1

      @@gheffz Idris for the programmers, Agda for the scientists :)

  • @davidmadar8894
    @davidmadar8894 18 วันที่ผ่านมา +159

    The name of the video is miseading, in my opinion. This is not really a proof that 1+1=2, but a proof that the definition of addition presented here is consistent with the result "1+1=2". If it wasn't consistent, the conclusion had not been that 1+1 does not equal 2, but that our definition for addition is faulty. This kind of proof put the result as something we want to achieve, because we assume it is true intuitively but lack the formal tools to describe it: we try to build a system of axioms and definitions that will lead to the result we wanted it to lead, and than we prove we succeded. Therefore it is meaningless to say we "proved that 1+1=2". What we did was finding an extremely elegant definition for addition that is consistent with the intuitive idea we already had and just wanted a formal set of axioms that will lead to it. This definition, or an extension of it, might become interesting and useful when it comes to adding things we don't have intuition about, such as infinity.

    • @catbertsis
      @catbertsis 13 วันที่ผ่านมา +24

      Agreed. Axioms are supposed to be the basic self-evident truths, but there is no way that Peano axioms are more self-evident than the fact that 1+1=2.

    • @b3kstudio
      @b3kstudio 12 วันที่ผ่านมา +4

      The video proved that "1+1=2 under the Peano axioms", and mentioned that the Peano axioms give us natural numbers, that are identical to the natural numbers we intuitively know. Thus 1+1=2. Proving the equivalency of the two groups would be a different proof.

    • @catbertsis
      @catbertsis 12 วันที่ผ่านมา +14

      @@b3kstudio This video heavily implies that the Peano axioms are in some sense more fundamental that basic properties of natural numbers, without really explaining why. That's why it has left me a bit frustrated.

    • @b3kstudio
      @b3kstudio 12 วันที่ผ่านมา +1

      @@catbertsis I think it depends on how you look at it. You could argue, that there is nothing more fundamental than taking a pile of one sticks, and another pile of one sticks, and putting them together. But that happens to be the same as the Peano axioms. Which one is more fundamental? Piles of sticks, for which you need sticks, which are arguably quite complicated by themselves, or 4 laws that can be used to represent the same thing.
      In the end, I think saying "this pile is 1, and this pile is 2" then taking two piles of 1 and putting them together is not a worse proof in any way, than the one in the video. Because really, 1+1=2, because we defined 1 and 2 that way.

    • @davidmadar8894
      @davidmadar8894 11 วันที่ผ่านมา +2

      @@b3kstudio formally. you are right, of course. But the motivation of such a proof is not to prove that 1+1=2, but to prove that Peano Axioms are worth something and not leading to results we don't want. From that point of view, "1+1=2" was the result we wanted to have and the Peano Axioms were the axioms needed to achieve that - they are the starting point from the point of view of Logic, but not from the point of you of what we really wanted to find.

  • @throughthoroughthought8064
    @throughthoroughthought8064 18 วันที่ผ่านมา +22

    My Second-grader says "nu-uh." And I can't disagree with them.

  • @Laicicles
    @Laicicles 3 หลายเดือนก่อน +109

    1:40 how can we use addition to define addition? How can that make sense?

    • @aminechakak6460
      @aminechakak6460 2 หลายเดือนก่อน +70

      look up what an inductive proof looks like.
      He's not using addition to define itself, he's using the base case over and over again as a function of counting to define addition.

    • @sibercraft7953
      @sibercraft7953 หลายเดือนก่อน +11

      It's as said before an Inductive definition such as for the factorial: if a (different) 0, then a!=(a-1)! x a ,Else (a=0) a!=1. You don't use the operation to define it. You define it by an operation that you already know (multiplication for the factorial,successor for the addition) on the previous term. And by having defined the first term, you have define Ur operation for every terme, since the first term is always reach

    • @tonydai782
      @tonydai782 22 วันที่ผ่านมา +6

      You just repeat applying the definition if it’s not the base case until you get to the base case, where there is no such holdup.

    • @williamhorn363
      @williamhorn363 22 วันที่ผ่านมา +1

      Addition itself is an axiom, so it is not being used to define itself. It is just being defined.

    • @epsilon.sw_
      @epsilon.sw_ 20 วันที่ผ่านมา +5

      We do not define the abstract essence of 'addition', but rather each specific case. Each case makes sense because it is reduced to the basic one, which is defined as true.

  • @Bodyknock
    @Bodyknock 18 วันที่ผ่านมา +11

    0 is very often included as a Natural Number when you are using set theory as the underlying basis since the Naturals are then defined as being the set of all possible finite cardinalities, and since the cardinality of the Empty Set is 0 that makes it a Natural Number.
    Where 0 isn’t usually included as a Natural Number is when you’re working in Number Theory since 0 is an annoying exception in a lot of theorems involving factorization. It’s simply more convenient to define the Naturals as starting at 1 in that context so you don’t have to keep dealing with 0 as a special case.

  • @zyphre
    @zyphre 25 วันที่ผ่านมา +111

    You define addition with addition?? how is that proof bruh.

    • @Open__56
      @Open__56 21 วันที่ผ่านมา +18

      I'm with you, he makes no sense

    • @miguelf218
      @miguelf218 19 วันที่ผ่านมา +47

      It's a recursive definition. It wouldn't make sense without the base case a+0 = a. If you think about it and look for it on the internet, you'll see that it was a great choice to define things that way since you can prove a lot of things with the induction principle

    • @oop9751
      @oop9751 19 วันที่ผ่านมา +1

      If I give you a iPhone at 7:39 and another iPhone at 7:39 how many iPhones would I have given you?

    • @Gus-s9v
      @Gus-s9v 18 วันที่ผ่านมา

      It will eventually go to another definition

    • @TS-cs2pe
      @TS-cs2pe 16 วันที่ผ่านมา +2

      Recursion

  • @TheLuckySpades
    @TheLuckySpades 7 หลายเดือนก่อน +30

    So 0 or 1 being the initial natural is actually a big split in conventions, in ny experience German speaking areas were more likely to start with 1, French and English speaking with 0, though English was the most mixed of the bunch
    And this split goes back even before Peano pubished his formalization, he was actually beaten to the punch by Dedekind (his formalization is equivalent, but also harder to state and closer to second order logic than first order)
    In Dedekind's initial manuscripts he started at 0, but somewhere in the process he began starting it at 1, he never wrote down why he changed it, but if I were to guess, the way he was approaching proofs became more elegant and simpler to write after the change, others went with 0 because their approaches had the opposite side for elegance

    • @tri99er_
      @tri99er_ 4 หลายเดือนก่อน +2

      0 indeed is not always considered a natural number, but it can be included, if needed. Also this way of addition extends to every whole number, not just naturals, so it is accepted here for convenience.

  • @DoxxTheMathGeek
    @DoxxTheMathGeek หลายเดือนก่อน +2

    I love this proof so much! X3
    Gonna become a preschool teacher to show the kids this thing so they are even more terrified for the next 10 years. :3

  • @Peacemaker8D
    @Peacemaker8D 7 หลายเดือนก่อน +34

    Wish these videos were out 12 years ago. Been wishing for an understandable explanation since high school, thank you so much!!!

  • @balooojeffersong4234
    @balooojeffersong4234 2 หลายเดือนก่อน +1

    I call this many cats 🐈‍⬛ one I call this many cats 🐈‍⬛ 🐈‍⬛ two if a put one cat next to one cat 🐈‍⬛ 🐈‍⬛ I now have 2 cats. Proved. Go home people

  • @akialter
    @akialter 16 วันที่ผ่านมา +5

    We invented 1+1=2 to describe one apple and one apple equals two apple. And now we go full circle to prove what we define

    • @chaudhryALIG
      @chaudhryALIG 12 วันที่ผ่านมา

      That's true, but some mathematical experts disagree with us .

  • @tombaron5607
    @tombaron5607 12 วันที่ผ่านมา +4

    Yes but can you prove that 6 was in fact scared of 7?

  • @jacob_90s
    @jacob_90s 6 หลายเดือนก่อน +11

    It is interesting how often in science and math the most tangible things are often the hardest to define in abstract terms.

  • @SpeedySonicX7
    @SpeedySonicX7 18 ชั่วโมงที่ผ่านมา +1

    I’m no mathematician, but I don’t think this is possible. Math is a form of representation. Assigning numbers to things is a uniform way to represent otherwise dissimilar and discrete things with one symbol. If I have a sheet of paper and a cup on my desk, I say there are two things on the desk not because the objects share some material property, but because I choose to represent them abstractly. This eliminates the need for me to be able to perceive a difference in the material objects, so long as I reason that they are indeed not the same object. So if I individually call those objects ‘one,’ I can declare that one ‘one’ and another ‘one’ makes ‘two.’ This verdict of nomenclature isn’t a mathematical law-it’s arbitrary. There’s nothing about the cup that makes it ‘one.’ In other words, the logic that outlines the definition of a number and affirms that 1+1=2 isn’t axiomatic. The validity of the statement is implicitly asserted to make mathematics’ epistemological laws possible, which all ultimately collapse when tasked to explain themselves, much like the paradox of trying to explain language using language.

  • @retrogamingfun4thelife
    @retrogamingfun4thelife 7 หลายเดือนก่อน +9

    if only youtube existed when Russell tried to proof the same thing! ;)

    • @odysseas573
      @odysseas573 7 หลายเดือนก่อน +1

      I am still waiting for a math video on TH-cam titled "The man who ALMOST broke math"

  • @Ryan-fq9dj
    @Ryan-fq9dj 13 วันที่ผ่านมา +1

    I need proof that this proof is legitimate before coming to the conclusion that 1+1=2

  • @robertlunderwood
    @robertlunderwood หลายเดือนก่อน +10

    It took 379 pages to prove this in Principia Mathematica.

    • @zemm9003
      @zemm9003 หลายเดือนก่อน +3

      This is because the concepts weren't well understood. Nowadays it's much simpler. Because we have solid foundations for both Peano Arithmetic and models in Set Theory (so whatever method you choose to prove it with is straightforward).

    • @prototypeinheritance515
      @prototypeinheritance515 23 วันที่ผ่านมา +5

      it didn't take 400 pages to prove 1 + 1 = 2; the authors used that space to establish an entire new foundation of mathematics notation and definitions, and then they just happened to prove 1 + 1 = 2

    • @throughthoroughthought8064
      @throughthoroughthought8064 18 วันที่ผ่านมา +1

      I thought they didn't quite finish it.

  • @JustifiedNonetheless
    @JustifiedNonetheless 19 วันที่ผ่านมา +1

    Prove "1" = "one" and that "2" = "two."
    For that matter, prove "1" or "one" = the concept to what they refer. You can't. These things are only true because we stipulated them as such. We could just as easily have stilulated the numeral "1" to correspond to the word "eight," and for both of those to correspond to the idea of 962.

  • @ferlywahyu342
    @ferlywahyu342 3 หลายเดือนก่อน +1

    In other math 1+1=0 bro 😂 this math in namex planet 😂

  • @revtheobbyist
    @revtheobbyist 7 หลายเดือนก่อน +12

    "you 'probably' agree with me"

  • @studio48nl
    @studio48nl 11 วันที่ผ่านมา +1

    I'm not a mathematician, but you use an addition in the proof of adding?! S(1+0). Is that valid?

  • @maxlevel4425
    @maxlevel4425 11 วันที่ผ่านมา +1

    1+1=2 is not self-evident. Because it´s not always the case that one thing plus another thing just equals two of them. See, one idiot is just an idiot. But one idiot plus another idiot does not just give you two idiots, it gives you a problem.

  • @joelcraig9803
    @joelcraig9803 4 หลายเดือนก่อน +2

    You know, if you don't pay a university $100.000 dollars, you can just prove 1+1=2 by adding 1+1 together.

  • @Ninja20704
    @Ninja20704 7 หลายเดือนก่อน +7

    For a moment i thought you were going to talk abt the few hundred paged proof but at least this was a little more meaningful to think about.

    • @ZachAttack6089
      @ZachAttack6089 16 วันที่ผ่านมา +1

      This is essentially the same proof. For the one that takes hundreds of pages, most of the pages are used to define the rest of the Peano axioms that were mentioned in the video, so it's not actually hundreds of pages just to do 1 + 1 = 2. For that you only need successor and addition.

    • @Simchen
      @Simchen 9 วันที่ผ่านมา

      @@ZachAttack6089 The other Peano axioms are just that the successor function is injective and the axiom of induction. How do you need hundreds of pages for that? I think if one really writes hundreds of pages to prove that 1+1 = 2 that's not a proof that's an exercise in obfuscation.

  • @robertpenoyer9998
    @robertpenoyer9998 10 วันที่ผ่านมา +1

    It's not my purpose to sound like a complete rube, but speaking as a non-mathematician but someone who does appreciate mathematical truth and exactness, I think this sort of thing is a lot of nonsense. Imagine an ancient farmer with a goat, one goat. Now a second farmer brings the first farmer another goat, one goat. They put the second goat in the pen with the first goat and count and observe, "Hey, there are one, two goats. When we combine one goat plus one goat, we end up with two goats." Why must a proof that 1+1 = 2 be any more sophisticated than the observation of those farmers?

    • @colecube8251
      @colecube8251 4 วันที่ผ่านมา

      I'm just gonna copy and paste this comment cuz i think it answers ur question.
      @davidmadar8894
      13 days ago (edited)
      The name of the video is miseading, in my opinion. This is not really a proof that 1+1=2, but a proof that the definition of addition presented here is consistent with the result "1+1=2". If the conclusion had been that 1+1 does not equal 2, than our definition for addition is faulty. This kind of proof put the result of 1 + 1 = 2 as something we want to achieve, because we assume it is true intuitively but lack the formal tools to describe it. we try to build a system of axioms and definitions that will lead to the result we wanted it to lead, and than we prove we succeded. Therefore it is meaningless to say we "proved that 1+1=2". What we did was find an extremely elegant definition for addition that is consistent with the intuitive idea we already had. This definition, or an extension of it, might become interesting and useful when it comes to adding things we don't have intuition about, such as infinity.

  • @chrislorentz2911
    @chrislorentz2911 5 วันที่ผ่านมา +1

    Terrence Howard does not like this video 🤣🤣🤣

  • @dionysus1210
    @dionysus1210 23 วันที่ผ่านมา +1

    Thats ridiculus you answered the question with question itself so why 1+0=1 dont need these weird things tp prove that you have fingers in one hand open 1 finger also in another hand and approach them so there is 2 fingers thats all

    • @johnwarosa2905
      @johnwarosa2905 23 วันที่ผ่านมา +1

      fingers are not proof

    • @edg42
      @edg42 23 วันที่ผ่านมา

      Before symbols (conventions) there were fingers.

  • @kylelacey1212
    @kylelacey1212 17 วันที่ผ่านมา +2

    Is this the rube goldberg machine of arithmetic?

  • @Nkzil0501
    @Nkzil0501 7 หลายเดือนก่อน +9

    You are an inspiration sir ✨🙇

  • @thestrangehexagon
    @thestrangehexagon 7 หลายเดือนก่อน +3

    you haven't shown that n = m implies S(n) = S(m) which you use when you say S(1+0)=S(1). You also haven't shown why 1≠0. you could use 1=S(0) and S(n)≠n but that hasn't been shown either

    • @prototypeinheritance515
      @prototypeinheritance515 7 หลายเดือนก่อน +3

      S(n) is a function which is by definition right-definite; that is the property you're looking for.
      The second claim can't be proven from the axioms given in the video. The peano axioms have a statement for this: "zero isn't the successor of any number" or in first order logic, forall n: Nat, S(n) ≠ 0.

  • @rcnhsuailsnyfiue2
    @rcnhsuailsnyfiue2 4 วันที่ผ่านมา +1

    CGP Beige

  • @christressler3857
    @christressler3857 3 หลายเดือนก่อน +1

    Now do a video on the proof that 1+1=2 from Russell's and Whitehead's book, Principia Mathematica!😁

  • @christopherellis2663
    @christopherellis2663 7 หลายเดือนก่อน +1

    Zero is the absence of number. Fail

  • @hakkinen1998
    @hakkinen1998 14 วันที่ผ่านมา +1

    I’m dumber after watching this video than before it. Now I don’t even understand why 1 + 1 = 2.

    • @acidjumps
      @acidjumps 11 วันที่ผ่านมา

      You're gonna have to read Principia Mathematica

  • @Steven_Rowe
    @Steven_Rowe 3 วันที่ผ่านมา

    I think 1 plus 1 can be whatever number I want like 3, it matters not that it's wrong, but I'm offended if it's not therefore I'm right.
    Let's be honest we live in an age when you can pick your own gender.
    Facts and truth do not come into anything anymore. it's all about how you feel and not to hurt anybody.
    I can't believe in this enlightened age with the internet etc we have become so dumb.

  • @gyattrizz-v5n
    @gyattrizz-v5n 3 หลายเดือนก่อน +1

    if you have one cookie, and i give you another cookie…

  • @hnhl2770
    @hnhl2770 หลายเดือนก่อน +1

    This doesn't prove anything, it's a tautology. The "successor" is the sum of that number and 1. And you define the sum as the successor of... which is the sum of... which is the successor...

    • @kemcolian2001
      @kemcolian2001 หลายเดือนก่อน +2

      the successor function is not the sum of that number plus one. rather, the natural numbers are defined in terms of the successor function. S(0) is defined as 1. S(1) is defined as 2. S(2) is defined as 3. S(78) is defined as 79. etc.

    • @user-tk2jy8xr8b
      @user-tk2jy8xr8b 21 วันที่ผ่านมา

      No, it's not "n+1", it's "first goes 0, then goes 1, then 2, then..." without any assumption about addition, equality, or other relations/operations. They don't exist until you define them explicitly.

  • @Camman18family
    @Camman18family 3 หลายเดือนก่อน +1

    One view + One view = Two views , simple enough

  • @smittymcjob2582
    @smittymcjob2582 7 หลายเดือนก่อน +1

    I am no mathematician but this proof feels circular. You're trying to prove addition works the way it does and then you use its definition to assume A+0 is equal to A in order to proceed with your recursive proof of addition.
    Here's my proof for why 1 + 1 = 2. I don't even need language or name like one or two.
    If I take a 100 lb sack of grain up to the third floor and then come back down and take another sack of grain up to the same spot then you can bet your life I'm going to try to find out what happened to the first one if I don't see it where I left it. I don't even need to have names like 1 or 2 or addition. It's just a real life experience expecting the result of both my actions to be there when I'm done. Addition, an operation on which the entire field of mathematics is built is simply a formalization of this real life experience by humans where they expect both objects to be there if they repeat the operation of moving objects.
    Now imagine if real life was such that you would need to repeat a moving operation three times to get two objects (a built-in godly taxation system!) then I bet you that the addition operation in our mathematics would have been defined as 1+1 = 0 and 1+2=2 and 2+2=3 and the number axis would have been defined entirely differently with a different abstraction for natural numbers. And then we'd have youtube videos showing rigorous proofs on why 1+2=2 using the successor numbers or some other man-made concept.

    • @ianmccurdy1223
      @ianmccurdy1223 12 วันที่ผ่านมา

      It's called recursion, not circular logic and it's perfectly valid

  • @Garfield_Minecraft
    @Garfield_Minecraft 23 วันที่ผ่านมา +1

    math just make things up
    this is why I love math👍

  • @hvnterblack
    @hvnterblack 24 วันที่ผ่านมา +1

    Marhematicians. How to complicate simple stuff.

  • @eyalmenzel4511
    @eyalmenzel4511 2 วันที่ผ่านมา

    But you explained hiw to do sums, with sums. U cant define somthing with itself.Its like saying the word "small", by defenision, is somthing small. U cant say that

  • @shriram5494
    @shriram5494 4 วันที่ผ่านมา

    Absolute nonsense
    You can just keep feigning ignorance about proofs by saying “but what is ‘TRUE’”
    And
    “But what is “is””

  • @CatkinsonGD
    @CatkinsonGD 6 วันที่ผ่านมา

    Was taught growing up to always be skeptical and think critically. Wasnt sure about this one. Had to cover all my bases.

  • @oliverfranke7650
    @oliverfranke7650 วันที่ผ่านมา

    That's no proof. That's proving an axiom by using axioms that are based on this particular axiom.

  • @wing_103
    @wing_103 13 วันที่ผ่านมา +1

    o (1 circle) + o (1 circle) = o o (2 circles)
    Edit: In hindsight, this is technically visual proof and is not reliable for calculations.

  • @NicholsonNeisler-fz3gi
    @NicholsonNeisler-fz3gi 24 วันที่ผ่านมา +1

    I thought it was by definition

    • @gabrielbarrantes6946
      @gabrielbarrantes6946 23 วันที่ผ่านมา +1

      It is, this proof is wrong. This proves that 1+1=S(1) but of course the last step S(1)=2 is by definition... So not a proof, just a definition.

    • @NicholsonNeisler-fz3gi
      @NicholsonNeisler-fz3gi 22 วันที่ผ่านมา

      @@gabrielbarrantes6946 I think you could theoretically prove it by using set theory…

  • @michaplucinski142
    @michaplucinski142 13 วันที่ผ่านมา

    Nah, that's ridiculous...
    It basically says:
    a+b = a + b - 1 + 1
    Because
    a + b = S(a + c) and b = S(c), so b = c + 1 and c = b - 1
    Therefore
    a + b = S(a + b - 1)
    Which is just
    a + b = a + b
    They really try to make themselfs look smart by making obvious stuff weird....

  • @iseeyou8781
    @iseeyou8781 3 วันที่ผ่านมา

    After 53 years there are some things that I have learned are just true with ZERO interest in being proven correct. This is one. 🤣🤣

  • @furynick1620
    @furynick1620 4 วันที่ผ่านมา

    1+1=2 is more like a definition. You can come up with others that 1+1=3 as well.

  • @calebmurugan6327
    @calebmurugan6327 9 วันที่ผ่านมา

    question: if b=1 is the successor of 0 then wouldn't a=1 also be a successor of 0 the the equivalence of a+b would be S(0+0) which is 1. please help to explain

  • @IftiharAbdillah
    @IftiharAbdillah 9 วันที่ผ่านมา

    But why is S(1 + 0) = S(1)? How can you "proof" that 1 + 0 is 1? 0 is a real number and 1 can be real and natural. And now since we want the result of 0 + 1 we naturally going to use 1 as a real number. But after that we need to make it a S(1) which is a natural number. So how do we know 1 in real number is the same as 1 in natural number? I sound so stupid yapping like this😂

  • @brickmack
    @brickmack 8 วันที่ผ่านมา

    This proof is wrong. Addition is defined for all numbers. Not just naturals, or rationals, or reals. And it works the same for all types of numbers as well. And there is no discrete "successor" to anything except a natural number. You can't prove someone about the general case using a function defined only on a subset

  • @Gelster
    @Gelster 2 วันที่ผ่านมา

    This is the math equivalent of having to meet the minimum 1000-word count in your essay

  • @rip_zogratis
    @rip_zogratis 2 วันที่ผ่านมา

    WAIT! think 1 water droplet plus another water droplet is 1 water droplet

  • @demonking86420
    @demonking86420 4 วันที่ผ่านมา

    Shouldn't you have used Whole Numbers set? Whole Numbers is Natural Numbers set plus Zero

  • @criticalangle90
    @criticalangle90 2 วันที่ผ่านมา

    Bertrand Russell approves. Now, prove that 1 + 2 = 3

  • @altissimo4158
    @altissimo4158 7 วันที่ผ่านมา

    S(a+c)? But there is a 'plus' sign inside! It does not form a proper definition if you define something with itself.

  • @snithnorddarthbathrobe6928
    @snithnorddarthbathrobe6928 9 วันที่ผ่านมา

    i can't understand this video because you're assuming I know what words mean

  • @bombasticcat
    @bombasticcat 2 วันที่ผ่านมา

    imagine a universe where 1+1 is a hard problem and people have to study to understand it.

  • @andrewscruggs5906
    @andrewscruggs5906 9 วันที่ผ่านมา

    I don't understand why you'd need to "prove" this. Addition is an operator, a function. It is defined. It is defined as two when inputing 1 and 1. 1•1 -> 2

  • @gejost
    @gejost 10 วันที่ผ่านมา

    Thought it's by definition; i.e,. 2 is defined as being the successor of 1. What suggests thr operation isn't well defined?

  • @akuunreach
    @akuunreach 18 วันที่ผ่านมา +2

    everyone knows 1 + 1 = 10
    we all need to get on the binary train

  • @CaptainJeoy
    @CaptainJeoy 7 วันที่ผ่านมา

    The way you ended the video is sorta funny 😅 The way "If you really want to up your math game" just abruptly came in

  • @Mike_Rottchburns
    @Mike_Rottchburns 4 หลายเดือนก่อน

    ERrRrR but then how do you prove that? And how do you prove that? Proving math is just a goddamn paradox

  • @pedzsan
    @pedzsan 12 วันที่ผ่านมา

    Bahh… An axiom is something that has been agreed upon. An assumption. We could just as easily say that 1+1=2 is an axiom and be done.

  • @kookaburra.boogie
    @kookaburra.boogie หลายเดือนก่อน +2

    This proof is beautiful. Thanks

  • @roaaarrry
    @roaaarrry 11 วันที่ผ่านมา

    Does this proof by describing subsequent numbers as successors still work if you are looking at real numbers rather than natural?

  • @ajdndbdjbdj
    @ajdndbdjbdj วันที่ผ่านมา

    Youre not making watch this lul bro

  • @LightmareQ
    @LightmareQ 9 วันที่ผ่านมา

    Or just stick to the take one object and then take another of that, you'll have two. I'm convinced.

  • @DeadlockHolmes
    @DeadlockHolmes 6 หลายเดือนก่อน +2

    Yes but why S(1)=2 ? Because S(n)=n+1 ? But why ? And what is n+1 if we use S to define addition. And if u dont use addition, I feel like at the end of the day you use « intuition » (the one we avoided at the beginning) to define what is a Successor

    • @user-tk2jy8xr8b
      @user-tk2jy8xr8b 22 วันที่ผ่านมา

      That's how naturals numbers are defined via Peano axioms. So, 1 is defined as S(0), 2 is defined as S(1)=S(S(0)), 3 is defined as S(2), and so on. S is not "plus one", it's "next", so 0 is the first, 1 is next, then goes 2 etc. There is no intrinsic addition or multiplication, just a sequence of things. You can define an addition over them, the video shows you how. You can also define multiplication: a * 0 = 0; a * S(b) = a + (a * b). Funny enough, you don't even have equality out of the box. Let's define it: 0 == 0 = True; S(a) == S(b) = a == b; _ == _ = False

    • @daniiltonkonog186
      @daniiltonkonog186 14 วันที่ผ่านมา +1

      S(1)=2 because 2 is just a symbol that means nothing . I mean we can define set of natural numbers as N = {0, S(0), S(S(0)), S(S(S(0))), and so on …}. Numbers are just a symbols.

    • @user-tk2jy8xr8b
      @user-tk2jy8xr8b 13 วันที่ผ่านมา

      @@daniiltonkonog186 right, we can also talk about bijections between {Z,S(Z),S(S(Z)),S(S(S(Z))), ...}, {0,1,2,3,...}, {zero,one,two,three,...}, and other sets that enumerate natural numbers

  • @shrijjithnatakala
    @shrijjithnatakala หลายเดือนก่อน

    bro at on video: "1+1=2" and on the next video: (9)^sin^2 x + (9)^cos^2 x =6💀

  • @redder-l8c
    @redder-l8c 7 วันที่ผ่านมา

    I recommend y all checking out type theory, you can actually implement addition in prog languages like agda

  • @VacouslyTrivial
    @VacouslyTrivial 24 วันที่ผ่านมา +1

    This could be generalized by adding the fact that 1+1=2 is e true iff it's belong to ordered ring(if a ≤ b then a + c ≤ b + c.
    if 0 ≤ a and 0 ≤ b then 0 ≤ ab. In fact one can check by replacing usual addition with modulo addition and simply 1+1 mod 2=0 and so the statement is false) and it's multiplicative identity which is 1 and additive identity which is 0 don't coincide i.e 1=0 and 1+1=0+0=0 false otherwise its true and the ring which 0 and 1 belong to it it's trivial

  • @EscapeFromDaSystem
    @EscapeFromDaSystem 5 วันที่ผ่านมา

    just clicked this cause i’m getting into Godels therum even tho i don’t do any maths