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Why is natural log abbreviated as ln and not nl ?

  1. Jan 28, 2014 #1


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    Why is natural log abbreviated as "ln" and not "nl"?

    I've been taking calculus for a while now and I was just wondering why natural logarithm is abbreviated as "ln" and not "nl". I'm just curious!
  2. jcsd
  3. Jan 28, 2014 #2
    There are many languages that place adjectives after nouns.. I highly doubt the idea was first published in English.
  4. Jan 28, 2014 #3


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    Hmm... interesting. I actually heard it was from Latin, but I just randomly saw that on the internet.
  5. Jan 28, 2014 #4
    Latin has adjectives after nouns.
  6. Jan 28, 2014 #5

    D H

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    Exactly. The "natural logarithm" in English is the logarithmus naturalis in Latin. Back in the day, it was Latin rather than English that was the lingua franca of the technical community.
  7. Jan 29, 2014 #6
    That post must be your magnum opus. :tongue:

    But it's true, Latin has not much in the way of word order. Either way is usually just as good as the other.
  8. Jan 29, 2014 #7
    The idea, no. But the notation, yes. The first use of ln is attributed to New York-born Irving Stringham in 1983. This is beyond historical doubt. Nobody has ever found an earlier use of the notation. Stringham got his degree from Harvard and was a professor of math at Berkeley. The notation ln is an American invention all the way.


    The truth of the matter is that nobody knows what ln is intended to mean. Nobody ever wrote down "ln stands for logarithmus naturalis," or "ln stands for Napier's logarithm," or any other explanation. All definitive answers in this thread are idle speculation. Stringham never bothered to explain it.

    See also

    http://www.pballew.net/arithme1.html#ln for a detailed account of the terminology and notation. That page shows an excerpt from Stringham's 1893 book, in which he states that the natural logarithm is notated "ln" without providing any explanation at all. Could be Latin, could be for Napier, could be anything.
    Last edited: Jan 29, 2014
  9. Jan 29, 2014 #8


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    Typo. You mean 1893 when, as you say, his book was published. Good post though.
  10. Jan 31, 2014 #9
    In portuguese (my idioma) we speak Logaritmo natural (ln)
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