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From: weiss@theory.lcs.mit.edu (Paul G. Weiss)
Newsgroups: comp.lang.prolog
Subject: Re: origin of "arity"
Message-ID: <WEISS.91Jun20144107@toucan.lcs.mit.edu>
Date: 20 Jun 91 18:41:07 GMT
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	<1991Jun20.005326.17063@athena.cs.uga.edu>
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In-Reply-To: mcovingt@athena.cs.uga.edu's message of 20 Jun 91 00:53:26 GMT

I also don't know who first coined it (I'm ashamed to admit), but I do
remember back in college I took a combinatorics course and we were
discussing polynomials.  A polynomial was classified as an n-ary p-ic,
where n was the number of variables and p was the degree, for example
a binary cubic (2-ary 3-ic) has 2 variables and degree 3.  The nouns
arity and degree were used to refer to n and p, i.e. 
"an n-ary p-ic polynomial" = "a polynomial of arity n and degree p".

This branch of mathematics and (I believe) this terminology goes back
to the nineteenth century.  A related question is when did the noun
"degree" receive the above meaning?

-Paul Weiss
-Arity Corp.