Drexel dragonThe Math ForumDonate to the Math Forum

Ask Dr. Math - Questions and Answers from our Archives
_____________________________________________
Associated Topics || Dr. Math Home || Search Dr. Math
_____________________________________________

The Symbol for Natural Log


Date: 06/28/2000 at 23:57:20
From: Adam Abrams
Subject: Natural law

Why is natural log abbreviated as "ln" and not "nl?" Please, I am just 
curious.

Adam Abrams


Date: 06/29/2000 at 12:56:17
From: Doctor Rick
Subject: Re: Natural law

Hi, Adam.

According to Jeff Miller's "Earliest Uses of Various Mathematical 
Symbols" (which you can find from our Dr. Math FAQ page) at:

   http://jeff560.tripod.com/mathsym.html   

the symbol "ln" first appeared here: "ln (for natural logarithm) was 
used in 1893 by Irving Stringham (1847-1909) in _Uniplanar_Algebra_."

His name doesn't sound French, but my theory is that there is a French 
influence in this and other naming conventions. In French, the 
modifier "natural" would follow the noun "logarithm." In the same way, 
the International System of Units is called the SI, not the IS, 
because in French it's Systeme International d'Unites.

French influence or not, the way we use subscripts follows the same 
pattern. A subscript modifies the meaning of the main variable, and we 
put it *after* the variable. For instance, Avogadro's number is called 
N_A (N-subscript-A), not A_N; the A for Avogadro qualifies the N, and 
it is put after the N.

This way of writing is very natural to mathematicians; it makes sense 
to put the more general first, and the qualifiers or the more specific 
after. 

     "What are you talking about?" 
     "Logarithms!" 
     "What KIND of logarithm?" 
     "Natural!" 

So the notion of writing "nl" seems very odd to me, and "ln" is more 
natural (no pun intended).

- Doctor Rick, The Math Forum
  http://mathforum.org/dr.math/   
    
Associated Topics:
High School Definitions
High School Logs

Search the Dr. Math Library:


Find items containing (put spaces between keywords):
 
Click only once for faster results:

[ Choose "whole words" when searching for a word like age.]

all keywords, in any order at least one, that exact phrase
parts of words whole words

Submit your own question to Dr. Math

[Privacy Policy] [Terms of Use]

_____________________________________
Math Forum Home || Math Library || Quick Reference || Math Forum Search
_____________________________________

Ask Dr. MathTM
© 1994-2013 The Math Forum
http://mathforum.org/dr.math/