Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.
  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
ModelOfTheory's profile
Model Of Theory
Model Of Theory
Model Of Theory
@ModelOfTheory

Tweets

Model Of Theory

@ModelOfTheory

ZFC, THIS.

Joined July 2016

Tweets

  • © 2018 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Categories with Jules‏ @_julesh_ May 19

      I've completed the most important part of the preparation for writing a book: designing a 'cat box' for more advanced category-theoretic side remarkspic.twitter.com/Goc9kzJLZO

      3 replies 7 retweets 44 likes
    2. John Carlos Baez‏ @johncarlosbaez May 19
      Replying to @_julesh_

      Now who could have made such an annoying, useless remark? 🤨

      1 reply 0 retweets 2 likes
    3. Categories with Jules‏ @_julesh_ May 19
      Replying to @johncarlosbaez

      This is an ancient functional programming meme, it's jokingly mis-attributed to Phil Wadler. I have no idea who actually said it first

      2 replies 0 retweets 1 like
    4. Matt Kukla‏ @n_category May 19
      Replying to @_julesh_ @johncarlosbaez

      There's evidence to suggest that Mac Lane said (a variant of) it first...pic.twitter.com/ardJM5hvKJ

      1 reply 0 retweets 2 likes
    5. Categories with Jules‏ @_julesh_ May 19
      Replying to @n_category @johncarlosbaez

      But Mac Lane was a (the?) category theorist so he had an excuse ... this meme is partly about functional programmers making fun of category theorists, or at least of other functional programmers who explain things using ct

      1 reply 0 retweets 2 likes
    6. Matt Kukla‏ @n_category May 19
      Replying to @_julesh_ @johncarlosbaez

      Fair enough. I figured the Mac Lane quote was close enough to the meme to be mentioned

      1 reply 0 retweets 0 likes
      Model Of Theory‏ @ModelOfTheory May 19
      Replying to @n_category @_julesh_ @johncarlosbaez

      I don't get this meme, because I don't see a way of thinking about monads other than as a monoid in the category of endofunctors.

      3:51 PM - 19 May 2018
      • 2 Retweets
      • 2 Likes
      • Content of Media Mark Hopkins funky & low volume
      4 replies 2 retweets 2 likes
        1. Categories with Jules‏ @_julesh_ May 20
          Replying to @ModelOfTheory @n_category @johncarlosbaez

          Moggi's thesis says that a program X -> Y that can do side effects is equivalently a kleisli arrow X -> T(Y) where T is a monad describing the sort of side effects you get. 'Monad' is precisely what you need to make composition well behaved. 'Monoid in endofunctors' is irrelevant

          0 replies 0 retweets 1 like
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo
        1. New conversation
        2. Referent Of Self‏ @ReferentOfSelf May 20
          Replying to @ModelOfTheory @n_category and

          Just take the definition and break it down into parts. Like thinking of a group as a set with a unital associative and invertible binary operation instead of a category with one object where all morphisms are isomorphisms

          2 replies 0 retweets 2 likes
        3. Categories with Jules‏ @_julesh_ May 20
          Replying to @ReferentOfSelf @ModelOfTheory and

          I guess the main problem is Haskell isn’t expressive enough to talk about “the category of endofunctors” directly

          0 replies 0 retweets 0 likes
        4. End of conversation
        1. New conversation
        2. Matt Kukla‏ @n_category May 19
          Replying to @ModelOfTheory

          I'm in this situation as well – I learned monads from the viewpoint of CT, so a monad is nothing but a monoid in the category of endofunctors to me. A lot of functional programmers are offended by this definition...

          1 reply 0 retweets 2 likes
        3. Darin Morrison‏ @freebroccolo May 19
          Replying to @n_category @ModelOfTheory

          I never understood this joke as programmers making fun of category theorists or even about them being offended. I've always understood it as (a certain subset of) functional programmers making fun of themselves for using something seemingly esoteric to explain a simple concept.

          1 reply 0 retweets 4 likes
        4. Categories with Jules‏ @_julesh_ May 20
          Replying to @freebroccolo @n_category @ModelOfTheory

          This might be right. Well, by Dawkins' original reasoning memes don't need to have a purpose, they just need to spread successfully

          0 replies 0 retweets 0 likes
        5. End of conversation
        1. Darin Morrison‏ @freebroccolo May 19
          Replying to @ModelOfTheory @n_category and

          On a technical note, relative monads cannot be expressed directly as a monoid in this way because T is not an endofunctor and cannot be iterated. There is a skew-monoidal presentation that apparently suffices but the "extension system" presentation common in CS is perhaps simpler

          0 replies 0 retweets 2 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2018 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Cookies
        • Ads info