What is Lambda Calculus? (ft. Church Encodings)

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  • Опубліковано 1 лют 2025

КОМЕНТАРІ • 68

  • @tho_norlha
    @tho_norlha 3 роки тому +35

    thank you, i have a scala exam in 10 days and you explain way better than my phd teacher who invented Scala

    • @leo848
      @leo848 2 роки тому

      Scala is a great Language, much better than Java

  • @xXyournewbestfriendXx
    @xXyournewbestfriendXx 5 років тому +27

    I watched a few videos about lambda calculus but now it finally clicked for me. Thank you!

  • @chloerevil4679
    @chloerevil4679 4 роки тому +2

    THANK YOU, you just explained in a sooo simple way something that I couldn't understand on any website or in my class.

  • @caligula2167
    @caligula2167 5 років тому +22

    Thank you for the video, Alex! Good stuff, as always!
    I just wanted to add that one may use this mnemonic to help them understand a Church numeral in a real-life scenario - a Church numeral is basically the number of times you would apply a function f to value x!
    x - Church's zero
    f(x) - Church's one
    f(f(x)) - Church's two
    f(f(f(x))) - Church's three

  • @SergioGarcia-bb8mr
    @SergioGarcia-bb8mr 4 роки тому +57

    Anyone else find the music distracting?

  • @johnshepard3197
    @johnshepard3197 Рік тому

    You did it so well! What would I have done if it was not for your video, lol. Love you, man!

  • @jetison333
    @jetison333 3 роки тому +11

    Thanks for starting at the bottom and building your way up, instead of starting from the top and using things you haven't explained yet.

  • @boburnhamsguitar
    @boburnhamsguitar 4 роки тому +1

    This is a beautifully created video! love how you explained thankyouuu

  • @brangusbrangus1802
    @brangusbrangus1802 4 роки тому

    This was exactly the video I wanted. Way to see a gap in the market and fill it! Do addition next, plz.

  • @anaxolotl6637
    @anaxolotl6637 Рік тому

    Gordon doesn't need to hear all this, he's a highly trained professional.

  • @nekoill
    @nekoill 11 місяців тому

    Finally, good ol' Alonzo gets his recognition!

  • @andrewchen2349
    @andrewchen2349 2 роки тому

    Hello sir! You are awesome, and I can see you really like what you're teaching. Thank you so much for this video!

  • @trewqqwert2725
    @trewqqwert2725 3 роки тому

    Thank you. I watched a few videos and got confused. This video cleared up all my confusion.

  • @CryptoGemIta
    @CryptoGemIta 2 роки тому +5

    maybe without music so loud would be better this video, thanks anyway for the info

  • @youcefkebir9131
    @youcefkebir9131 4 роки тому +4

    did anyone ever told you that you're a life savior

  • @brendawilliams8062
    @brendawilliams8062 5 місяців тому

    Nice calm blue background. Thankyou

  • @gregorywilson2124
    @gregorywilson2124 Рік тому

    Very clear description

  • @genericperson8238
    @genericperson8238 3 роки тому +4

    The lambda calculus also had a big impact on imperative languages before it had an impact on declarative/functional ones

  • @rorycawley
    @rorycawley 3 роки тому

    Best video on lambda calculus

  • @bestieboots
    @bestieboots 3 роки тому

    This was so good!!!

  • @NewtonInDaHouseYo
    @NewtonInDaHouseYo 3 роки тому +4

    Good explanation. But the background music is a bit distracting for me.

  • @schrodingerscat4019
    @schrodingerscat4019 3 роки тому

    thanks from italy!!!! you are great

  • @nickscriabin5466
    @nickscriabin5466 3 роки тому +2

    Every time I come back to lambda calculus, all I want is for my life to end...

  • @mulchand_is_gaming
    @mulchand_is_gaming 2 роки тому

    ITS VERY USEFUL IN KNOWING BECAUSE WHEN YOU FELL LIKE THINGS ARE GOING COMPLEX YOU WILL KNOW THAT NOTHING IS COMPLEX ITS JUST THAT WE DONT KNOW THE ABSTRACTION BEHIND IT.

  • @lazargrbovic5358
    @lazargrbovic5358 3 роки тому +4

    Awesome video Alex, thanks! :)
    I have one question though, where could I find a bunch of Lambda Expression examples to practice?
    Best regards,
    Lazar Grbovic

  • @superrv0023
    @superrv0023 3 роки тому

    Finally I understood the concept ☺️

  • @amirabendahmane2824
    @amirabendahmane2824 2 роки тому

    thank you sooo much, that helps a lot.

  • @snipzmattio5887
    @snipzmattio5887 2 роки тому

    λ, great video

  • @davidprock904
    @davidprock904 4 роки тому +6

    2 min 51 sec into the video and pause it to say... you should really kill the background music 🎶... still having trouble understanding and now I'm doing extra work trying to filter out the music

  • @andrerenault
    @andrerenault 3 роки тому +1

    Maybe it's because I'm not a comp sci student, but I still don't get the purpose of lambda calculus - how does it make life better?

    • @plasticflower
      @plasticflower 2 роки тому

      It can be useful when you're coming up with a programming language, to sort of outline what you're planning to implement and have a solid set of rules that you can build on

    • @Zoey-wy7zj
      @Zoey-wy7zj 4 місяці тому

      The lambda calculus is important as it represents a model of computation. This is known as the Church-Turing thesis(Everything that can be calculated can be shown to be calculated by either a turing machine or the lambda calculus, as both definitions are equivalent.)
      If you want to prove that something can or cannot be calculated, then you can make an appeal to the lambda calculus or turing machines.

  • @vicvic553
    @vicvic553 4 роки тому +2

    I disagree with you. In the expression about nested function, i.e. lambaX.lambdaY.X it is f(X, f(Y)), wherr f(Y)=X, not f(X,Y). This is a huge difference.

  • @valentineoragbakosi378
    @valentineoragbakosi378 5 років тому

    Nice content 👍

  • @superoya9747
    @superoya9747 4 роки тому +11

    Please next time decreases the volume of music 😭

  • @TheRedPython
    @TheRedPython Рік тому

    I don’t get it? What is it used for? Seems a pretty long winded way to write 0 and 1

    • @stevendaryl30161
      @stevendaryl30161 Місяць тому

      It's actually very useful in making things clear in mathematics.
      It happens all the time that people define a function by writing down an expression that has a variable in it. For example, somebody might say something like: Consider the function x+1, or sin(2x). Those are not actually functions. They are instead incomplete expressions. But what's meant is the function that takes a value (or input) for x and returns a value that is computed from that. That would be expressed in the lambda calculus as:
      lambda x . x+1
      Or lambda x . sin(2 x)
      That might sound like a triviality. Of course, that's what it means. But if you've ever taken a mathematics class that uses functions and variables, there's always some ambiguity. Does sin(2 x) mean a function, or does it mean the value of a function at some point x?
      It becomes more ambiguous if you are talking about functions of multiple variables. Suppose I write the expression sin(x) + a. What is "a" here? Is it a constant that I just haven't told you the value of, or is it a variable? You can view sin(x) + a in two different ways:
      (1) For every choice of a, there is a corresponding function sin(x) + a. This is a family of related functions.
      (2) It's a function of two variables: x and a.
      Lambda calculus makes it clear which one you are talking about:
      lambda x. sin(x) + a
      is a function of one variable, and a is a "parameter".
      lambda x . lambda a. sin(x) + a
      is a function of two variables, x and a.

  • @YunusParvezKhan
    @YunusParvezKhan 2 роки тому

    After watching it for 5 munites while waiting on traffic, made me think that yeah it's hard 🙂

  • @jiggartala2008
    @jiggartala2008 3 роки тому

    I think you have mistake in explaining : lambdaX.lambdaY.X. you convert it to f(x,y)=x which I think is incorrect shouldn't be f(x)=f(y)=x ?

  • @keldsor
    @keldsor 4 роки тому +72

    KILL that music !!!!!!!!!!!!!!!!!!

    • @csillikd
      @csillikd Рік тому

      Why?Its like porn! :D

  • @cemozgur9959
    @cemozgur9959 4 роки тому

    🤯

  • @hikariwuff
    @hikariwuff 3 роки тому +4

    Even more confused. Thanks.

  • @viczking8520
    @viczking8520 4 роки тому +4

    Turn off music plz

  • @kerron68
    @kerron68 2 роки тому +1

    Music is too loud

  • @harimonting01
    @harimonting01 Місяць тому

    Next time please increase the music volume, I can still hear your voice.

  • @joeyb8006
    @joeyb8006 3 роки тому +1

    thanks, but the music was a bit much

  • @aisha3540
    @aisha3540 4 роки тому +2

    Personally loved the music!

  • @IsmailMarmoush
    @IsmailMarmoush 4 роки тому +8

    You literally made something great, and just ruined it with that music !

  • @leonhard.doerflinger
    @leonhard.doerflinger Рік тому

    The video would have been better without the music.

  • @GarethIngram
    @GarethIngram 5 місяців тому

    gave up, the music...

  • @noodleboi5053
    @noodleboi5053 Рік тому

    lose the music

  • @cookieBadger
    @cookieBadger 4 роки тому +1

    "So you can increment the zero value and get one, which is pretty crazy!"... ookay wow, so next you're gonna tell us that you can draw a line on a sheet of paper and call it "revolutionary"?

    • @paulus.schmaulus
      @paulus.schmaulus 4 роки тому +4

      Cmon, define a simple set of rules, which is so powerful and in essence simple as lamda calculus. With only 3 so incredibly simple rules, to be able to calculate any given computable function is huge.

    • @cookieBadger
      @cookieBadger 4 роки тому

      @@paulus.schmaulus I was just joking. Of course the people that came up with this had some mad mathematic skills. I just don't share your passion for calculation models, but still have to learn this at uni :D

  • @gloverelaxis
    @gloverelaxis Рік тому +1

    this music is REALLY bad and distracting

  • @Johannes00
    @Johannes00 3 роки тому +10

    Your video finally made me understand something I couldn't wrap my head around
    When you drew out what went where and how things interacted it became so clear
    Thank you!!
    Chaining lambda functions is complicated but fun to learn about
    My first project was to reverse three arguments given to the function
    (λx.λy.λz.z y x) A B C
    ⇒ (λy.λz.z y A) B C
    ⇒ (λz.z B A) C
    ⇒ C B A