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.

This is the legacy version of twitter.com. We will be shutting it down on June 1, 2020. Please switch to a supported browser, or disable the extension which masks your browser. You can see a list of supported browsers in our Help Center.

  • 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
richhickey's profile
Rich Hickey
Rich Hickey
Rich Hickey
@richhickey

Tweets

Rich Hickey

@richhickey

clojure.org
Joined June 2009

Tweets

  • © 2020 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • 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. Rich Hickey‏ @richhickey 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation

      Not having a thing is not the same as having an empty maybe-thing

      24 replies 91 retweets 364 likes
    2. Daniel Spiewak‏ @djspiewak 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @richhickey

      The negative hypothesis is always untestable. Rather than attempting to reason about absence directly, it is more useful to encode it in an explicit form.

      1 reply 0 retweets 8 likes
    3. Rich Hickey‏ @richhickey 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @djspiewak

      Huh. I don't think my driver's license has my phone number on it ... checks ... that's right, it doesn't.

      3 replies 0 retweets 15 likes
    4. Daniel Spiewak‏ @djspiewak 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @richhickey

      That seems like a rather imprecise phrasing. Let's make it more concrete: write a pure function which produces your phone number given a driver's license. What does it return?

      2 replies 0 retweets 0 likes
    5. Rich Hickey‏ @richhickey 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @djspiewak

      In the real world we can trivially ask and answer the question - Does your driver's license have a phone number on it? Also the question - what information does your driver's license have on it?

      3 replies 0 retweets 3 likes
    6. Daniel Spiewak‏ @djspiewak 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @richhickey

      You aren't talking about the phone number that you may or may not have (the thing/non-thing). You're talking about its meta-state. Which is to say, you've encoded Maybe.

      3 replies 0 retweets 1 like
      Rich Hickey‏ @richhickey 7 Sep 2018
      • Report Tweet
      • Report NetzDG Violation
      Replying to @djspiewak

      The premise was 'having' and questions involving 'having/not' are fundamental, not meta, and more primitive than the composite conveyance of 'answer' or 'don't know'. Does the license 'have' a maybe phone number, maybe cat picture etc, in the same way it actually 'has' my d.o.b?

      9:54 AM - 7 Sep 2018
      • 2 Likes
      • Simon Belak Scientific Coder
      2 replies 0 retweets 2 likes
        1. New conversation
        2. Daniel Spiewak‏ @djspiewak 7 Sep 2018
          • Report Tweet
          • Report NetzDG Violation
          Replying to @richhickey

          Fascinating perspective. Obviously this gets into coding theory (in the Gödel philosophical sense) if we treat it formally, but I'll go with the grammatical response. Your sentence: Does the license 'have' a maybe phone number. Mine: The license may have a phone number.

          1 reply 1 retweet 1 like
        3. Rich Hickey‏ @richhickey 7 Sep 2018
          • Report Tweet
          • Report NetzDG Violation
          Replying to @djspiewak

          You replaced a question with a sentence, let's fix: Is the fact that 'a license may have a phone number' reified? Must all the possible (not nonsense!) things a license might have be reified? Can I ask you questions about your license that your DMV has not yet considered?

          4 replies 0 retweets 1 like
        4. 3 more replies
        1. Daniel Spiewak‏ @djspiewak 7 Sep 2018
          • Report Tweet
          • Report NetzDG Violation
          Replying to @richhickey

          What we're playing around is sort of the meaning of "what does it mean to 'have' nonsense?" What does it mean to 'have' an answer to 1/0? What does it say about us when we believe we posses a thing that cannot exist?

          0 replies 0 retweets 0 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

        • © 2020 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info