If Two Minds Are Better Than One, Then How About Two Thousand?
A Review of Marvin Minsky's The Society of MindEvery once in a while, one encounters a book so strikingly fertile and original that after reading it, one can never be quite the same. Its ideas resonate, sounding depths in one’s everyday life, clarifying what was previously obscure and raising questions that one never even knew existed. Such a book is Marvin Minsky’s The Society of Mind. In this book, Minsky, arguably the foremost researcher in the field of artificial intelligence, shares with lay audiences ideas developed through many decades of careful thinking about how minds, natural and artificial, might work. The late Carl Sagan, a friend of Minsky’s, often lamented the fact that first-rate scientists rarely condescend to explain their work to nonspecialists. We can be greatful that Minsky saw the value in letting those of us who are not specialists in AI and robotics have a glimpse of his work.
The cornerstone of Minsky’s theory is the conception of minds as collections of enormous numbers of semi-autonomous, intricately connected agents that are themselves mindless. As Minsky puts it,
I’ll call “Society of Mind” this scheme in which each mind is made of many smaller processes. These we’ll call agents. Each mental agent by itself can only do some simple thing that needs no mind or thought at all. Yet when we join these agents in societies—in certain very special ways—this leads to intelligence. (17)
EYES Two circles, high in head.
MOUTH Object centered below eyes.
BODY Large closed figure.
ARMS Two lines, attached high on body.
LEGS Two lines, attached low on body.
2. IF such a feature is already drawn, go to step 3. Otherwise draw it.
3. IF list is finished, stop. Otherwise, go back to step 1.
Minsky is at pains to point out that much of what we take for granted is really incredibly complex. Early AI researchers soon learned that it was far easier to model on computers the kind of sophisticated, conscious knowledge that experts have in a given field than it is to model simple, largely unconscious abilities that we take for granted, such as remembering how to get to our homes, balancing ourselves on a bicycle, recognizing a parent’s face, or using language. As Minsky puts it, “Easy things are hard.(29)” Minsky points out that in the 1960s, he and Seymour Papert spent several years developing a program that would have the ability to build towers out of blocks. Such a Builder agent is itself made up of subagents such as Begin, Add, and End. Add is made up of the subagents Find, Get, and Put. Get is made up of the subagents Grasp and Move. All these mindless agents are connected in bureaucracies, in which agents report to other agents, and most of this work occurs below the level of consciousness, which is why it is so difficult to think clearly about them. As Minsky puts it,
At one point in this fascinating, accessible, yet challenging book,
Minsky quotes Wolfgang Pauli as saying, “That theory is worthless. It isn’t
even wrong!” Minsky would be the first to admit that many parts of his
theory are highly speculative. Even where Minsky’s ideas prove, one day,
to have been wrong, they will have yielded powerful results, providing
us with ways to begin thinking clearly about who we are and how we work.
Minsky has spent his life in a demanding field in which a theory of a process
is as good as the program that one can write or the robot that one can
build to instantiate it. Time and time again, in reading Minsky, one has
the satisfying feeling that one has when assembling a complicated appliance
and having it operate smoothly. Ah, yes, that works. And even when it doesn’t
work, by actually attempting to build the machine that instantiates the
theory, we can learn what parts don’t operate and begin to conceptualize
alternatives. One of the reasons why artificial
intelligence is important is that it provides a testing ground for psychological
theorizing, forcing theorists to make their thinking concrete and operational.
Minsky’s book is an example of operational thinking at its best and will
doubtless serve as a roadmap for much of the work in artificial intelligence
and cognitive psychology in years to come.
ReferencesMinsky, Marvin. The Society of Mind. New York: Simon and Schuster, 1986.
Minsky, Marvin. The Society of Mind CD-ROM, Macintosh Version. New York: Learn Technologies Interactive, 1996.
Minsky, Marvin. The Society of Mind CD-ROM, Windows Version.
New York: Learn Technologies Interactive, 1997.
|Questions for Discussion and Review
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