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From: port@iuvax.UUCP
Newsgroups: comp.ai
Subject: Re: daemons... where's the name from?
Message-ID: <119700002@iuvax>
Date: Sun, 29-Mar-87 18:10:00 EST
Article-I.D.: iuvax.119700002
Posted: Sun Mar 29 18:10:00 1987
Date-Received: Tue, 31-Mar-87 07:23:22 EST
References: <442@cord.UUCP>
Organization: Indiana University CSCI, Bloomington
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Nf-ID: #R:cord.UUCP:442:iuvax:119700002:000:1333
Nf-From: iuvax.cs.indiana.edu!port    Mar 29 18:10:00 1987


The use of daemon in Unix for a program that `wakes up' and
does some task whenever it is required is actually a
regular use of the word.  It isnt one of those typical
computing terms that has an arcane history (one thinks
of the derivation of `nroff, grep, awk, winchester,' etc).
	The word is classical Greek for any kind of spirit or
genie -- some kind of minor deity.  In Latin they borrowed
the Greek word and spelled it daemon (for Greek daimon-ion),
to descdribe such spirits.  For the Christians, of course,
all such deities were paganisms so, they were viewed
as evil.  Thus the English word demon has the strong
flavor of evil about it.  
	But we also seem to have split the word in two, 
so now the original pagan meaning has been restored in 
modern English with a more classical spelling as daemon.  
The use in `Maxwell's daemon' is in just this sense.
Similarly, in the 1950's Selfridge proposed a parallel model of
the perception of alphabetic letters that had `daemons' 
for each letter.  They were competing with each other
to `find themselves' in the incoming visual features.
The one that `shouted' the loudest was the one that
caused a `decision demon' to issue a conclusion.
	The use of this word for independent procesess
that seem to have a `will of their own' as in operating
systems is very appropriate.