Scheme for AI based CAI

[Tim Finin <Tim%upenn.csnet@CSNET-RELAY.ARPA>]

What follows is a msg from Mark Richer via the AIED digest concerning the
use of Scheme for building AI based educational systems.  I've included my
response.  Others may have relevant thoughts to share with him.

Tim
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From: Mark Richer <RICHER@SUMEX-AIM.ARPA> on Wed 11 Jun 1986 at 12:00
To:   ai-ed-outgoing@SUMEX-AIM.ARPA
Subj: 1:8 Scheme; AI-ED questionnaire

AI-ED Digest          Tuesday, 10 June 1986       Volume 1 : Issue 8

Today's Topics: Scheme, anyone?
		AI and Education questionnaire		

Date: Tue 10 Jun 86 08:29:38-PDT
From: Mark Richer <RICHER@SUMEX-AIM.ARPA>
Subject: Scheme, anyone?

I have been asked to give advice regarding the appropriateness of using
Scheme for a development effort in Intelligent Computer Assisted Instruction.
Although this is partly a research effort also, a clear goal is testing
and installing the software in high school classrooms.  The hardware available
to this project is HP workstations.

Admittedly I know little about Scheme.  However, my initial reaction is that
no advantages Scheme could provide over CommonLisp could offset the
disadvantages of using a language without a large user base for the
purposes of software development and installation.  CommonLisp
promises to offer portability (of course there are still problems, e.g.,
graphics) and a large user community, and has other obvious advantages 
because of the general acceptance of Lisp in the U.S. AI community.

I'd appreciate some feedback from people that are familiar with Scheme,
particularly if you have used it for developing a large AI-based system.
Can any argument be presented to justify the resources necessary to train
people in Scheme and build and maintain a system in this UnCommonLispLike
language? In other words, what is so special about Scheme compared to
CommonLisp?

Mark

... rest of digest deleted ...
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From: Tim Finin <Tim@upenn> on Wed 11 Jun 1986 at 12:49
To:   Mark Richer <RICHER@SUMEX-AIM>
Cc:   Bonnie Webber <bonnie@upenn>, Ai Bulletin Board <scheme@upenn>
Subj: Scheme

Here are some thought on Scheme vs. CommonLisp.  We use Common Lisp in our
research efforts (mostly) and Scheme as an instructional language.  We are
using it in both our graduate and undergraduate programs in the core
software/programming languages courses.

  Scheme is Lisp.  More precisely, Scheme is what Lisp should be modulo some
  software engineering arguments.  I think that the biggest influence on the
  development of Common Lisp was the success of Scheme as a language. The
  differences between common Lisp and scheme, as programming languages, at
  this point, are mostly surface level phenomina.  Common Lisp does have a
  much much bigger base of existing software, however.  
  
  Scheme will be the Pascal of the 90's. Scheme is fairly standardized.  There
  are a number of good implementations (CScheme, PC-Scheme, Chez Scheme,
  MacScheme) and all ashere to the unofficial standard (The Revised Revised
  Report on Scheme). I think it will be used in most of the good CS
  undergraduate programs in a few years to teach basic concepts of
  programming.  Common Lisp, I believe, will not be used in this way.  Thus,
  you can expect to see an increasing "user base".
  
  Scheme is simple. Scheme is inherently simpler and smaller than common lisp.
  There is some truth to the equation of sheme/commonlisp = pascal/ada.  I
  think Scheme will be a beter deliverey vehicle for AIED systems.  It will be
  hard to sell these systems if they need an HP Bobcat or a Vaxstation to run
  them.  It will be easy to sell them if they run on a PC or a MAC.  
  
I hope these thought are relevant.  Tim.