+1 for knowing your history

March 30th, 2011

“+1” is a convention that arose on the Apache Software Foundation mailing lists. The ASF still has the best, most functional process for mailing list based collaboration which has ever been evolved of which -1/0/+1 is only the thin wedge. (the whole vocabulary of lazy consensus, commit-then-review, etc is incredibly important when trying to implement a diversity of tactics over email, as we ran into time and time again with Indymedia). Worth exploring their process in depth.

Anyway, Google launched a “+1” product today, and there was some discussion as to where the “+1” convention came from. The first place I ever encountered it was this email from Rob Hartill, on Wed, 15 Mar 1995, as part of one of the early patch voting rounds on Apache 0.7.x (the Apache foundation having formed the previous month to turn NCSA httpd into Apache).

I'll use a vote of 
  -1 have a problem with it
  0 haven't tested it yet (failed to understand it or whatever)
  +1 tried it, liked it, have no problem with it.

Rob might have adapted it from an earlier source, but I’ve never seen it.

19 responses to “+1 for knowing your history”

  1. Matt McClure says:

    I always associate “plus one” with the usage for concerts or events:

    “A friend or date whom one brings along to an event.” [1]

    So in a voting usage, the person saying “+1” is saying I’m the one going along with you.

    [1] http://en.wiktionary.org/wiki/plus_one

  2. And every software org (e.g. OSGeo) that based their setup on the ASF’s have adopted it, as well.

  3. Matt Haughey says:

    Huh, I always thought it was a Slashdot-ism, from their circa-1999 implementation of karma voting. It seemed like everyone after that used to say “+1” in agreement on geek mailing lists as a sort of slashdot shorthand for “I agree”.

  4. I remember the Slashdot +1 convention Matt talks about but I also remember it from tech/geek mailing lists from the mid-1990s.

  5. Kellan says:

    It would be interesting to track the first non-Apache open source project to adopt the +1 convention. As I imagine that it was through that diffusion that it arrived in the /. comments.

  6. Nelson Minar says:

    I believe the +1/-1 convention dates back to at least 1993 with the voting for creating Usenet groups. I’m confident the voting mechanism was people voting “yes” or “no”; the yes votes needed a supermajority. I’m less confident about the +1 notation, but I recall using it in conversations. One lead on researching further: http://www.livinginternet.com/u/ua_create.htm

  7. Greg Stein says:

    I used it occasionally on the Python development lists, then formally introduced it here:


  8. Greg Stein says:

    oh, and I should note that Python did end up adopting the mechanism: http://www.python.org/dev/peps/pep-0010/

  9. R. T. says:

    Am I the only one who associates +1 with Dungeons and Dragons? This has been a nerd meme since the 70’s.

  10. @Nelson_Minar +1 (Usenet voting)

  11. Roger Weeks says:

    +1 was also widely used in IRC. I am fairly certain, although I have no IRC logs to prove it, that I was using +1 in IRC and Usenet at least by 1995, if not earlier.

  12. Stefano says:

    The legend I know says that the +1 meme was brought over from the FreeBSD community over to Apache but some of the original founders (which used to hang out in FreeBSD land). But I believe it’s fair to say that it was the ASF that first codified the notion of lazy consensus.

  13. rocky says:

    yep. +1 has long been applied to concerts and clubs, for the guest list. 1985 was when i started going out, and heard it. the computer biz just co-opted the term.

  14. R. says:

    RT, you’re not the only one. I also think it comes from D&D.

  15. MSchienle says:

    I’m with R. T. on the D&D reference, with an Apple II text adventure game called Wizardry from about 1984. It was used for upgrading your armor/weapon, as in Sword+2.

  16. Leonard Lin says:

    Yeah, I remember +1 well underway on various FidoNET echos and mailing lists when I got online in the early 90s.

    That being said, +1 for RSVP and guest lists is probably what I most associate it with.

    Works both ways I guess.

    For agreement (that includes a bit more ego/authorship implications) I like the IRC name++ convention.

  17. Kaleberg says:

    According to Google’s ngrams database, the phrase “plus one” grew increasingly popular in the late 19th century and peaked in the 1980s. It has since been in decline. (Interestingly, the phrase “plus four”, referring to men’s golfing knickers, seems to have followed a similar trajectory. “Plus two” and “plus three” seem to have gone a similar route, though with much less usage.)

    Granted, the phrase “plus 1” actually peaked at the end of World War II. I’ll leave the interpretation of all this to Randall Munro.

  18. Insomniac says:

    Kaleberg, Is that a typo and you mean 20th century or is there a non tech longer term usage from the 1800’s/19th century?


  19. dru says:

    I still instinctively use +0 to connote ambivalence, usually resulting in confusion amongst those I’m talking to.