From: colby@oahu.cs.ucla.edu (Kenneth Colby)
Newsgroups: sci.med
Subject: Colbys-Weizenbaum and Overcoming Depression 2.0
Date: 8 Jan 93 20:31:59 GMT
Organization: UCLA, Computer Science Department




	Colbys-Weizenbaum and Overcoming Depression 2.0

	One of the long-standing (and at times tedious) contro-
versies in AI involves the Colby-Weizenbaum argument over whether
it is immoral to use computers for psychotherapy.  Colby believes
computers should be used to help millions of mental sufferers who
(a) cannot afford private therapy, or (b) prefer not to consult a
mental health professional.  Weizenbaum believes using computers
for psychotherapy is simply immoral.  The argument is well-summarized
in "Paradigms Lost" by John Casti who quotes Colby (p. 327):

	"Over the past four centuries the scientific community has
	come to mistrust suppressions of inquiry, not only because
	they protect the status quo but because so often the
	finger-wagging moralist has turned out himself to be morally
	confused, piously self-serving, and irresponsibly blind to
	the consequences of his own oppresive actions".

	Casti adds - "This is the kind of sound advice that in my
opinion should flash on the screen before the appearance of every
politician and TV evangelist.  In the light of recent history, even
Jim Bakker and Jimmy Swaggart might now agree!"

	The controversy has been dormant for a few years until
recently, in an interview with Thomas J. Schult in the German
magazine c't, Weizenbaum attacks our (Peter and Kenneth Colby)
cognitive therapy program Overcoming Depression 2.0 claiming that
it is nothing but ELIZA (es wirklich nichte anderes als ELIZA)
(absolut ELIZA) and that it is a lie because it uses the pronoun
"I" (Ich) when "no one is there" ("niemand ist da").

	Overcoming Depression 2.0 consists of a text or educational
mode and a dialogue mode.  It is not "strong" AI and it is not
"weak" AI.  It is interventional AI using the computer program as a
tool to help allevaite depression.  Weizenbaum is mistaken in saying
the structure and function of the dialogue mode of Overcoming Depression
2.0 (OVD) is exactly that of ELIZA (absolut ELIZA).  He obviously
has not studied our program.  The clear differences are:

	(1) ELIZA has a data base of keywords in which each keyword
	is stored with an integer used to decide which keyword to
	respond to.  OVD uses a conceptual thesaurus, a semantic
	data base in which character strings, words, and phrasal
	expressions are assigned to semantic categories from which
	conceptual patterns are constructed.

	(2) ELIZA has no semantic deep structure.  Its pattern match
	takes place between the surface words of the input and a
	keyword pattern.  OVD creates sets of conceptual patterns
	using a combination of heuristic and grammatical rules.
	The patterns created are interpretations that serve as the
	left-hand sides of production rules.  A variety of criteria
	are used to select the conceptualization that will be
	responded to.

	(3) ELIZA uses surface words from the input as part of its
	output.  OVD does not.  Its outputs are the right-hand sides
	of the program's production rules.

	The charge that OVD is a lie (eine Luge) is based on the
weird argument that the program outputs "I" expressions ("I think
you are right") but there really is no "I" there (da ist kein ich).
The deictic pronoun "I" refers to the speaker--whoever uses it.
In the case of OVD, the "I" obviously refers to the designer of
the program, one step removed.  The computer is a stand-in proxy
for the program designer.  The computer program here is being used
as a linguistic tool, a medium through which the programmer
communicates his interests and concerns as in a high-speed
correspondence of written utterances. Weizenbaum seems to believe
there must be a person inside the box for therapeutic dialogue to
be conducted, much as small children believe there must be people
in the TV set.

Peter M. Colby
Kenneth Colby
M.A.I.W.
colby@CS.UCLA.EDU

Copies of the original Weizenbaum interview (English translation)
are available by E-MAIL.