Computing Revievs · May 1996
FRANKLIN, STAN (Univ. of Memphis. Mcmphis. TN)
Artificial minds.
MIT Press. Cambndge, MA. 1995. 449 pp., $30. ISBN 026206 1783.
As artificial intelligence (Al) has matured, it has provided a unified home
for approaches to intelligence that manipulate symbolic xpresentations of
knowledge. Research into other, nonsymbolic approaches to computational
intelligence is much less accessible, scattered thmugh a dozen disciplines
and hundreds of different conferences, joumals, and books. Franklin seeks
to pull these scattered threads together to understand how one might implement
intelligence on a machine. His approach is unabashedly infortnal and conversational.
Though a mathematician and a researcher, he assumes the role of an amateur
toward most of the technologies he discusses. and explicitly pt~sents the
book as a tour of various research projects that he has found of interest.
The first three chapters set the tone. Chapter I, "Mechanisms of Mind,"
descnbes the domain that Franklin proposes to cover. He class)fies existing
approaches as topdown versus bottomup and analytic versus synthetic. His
focus includes AI and a bottomup synthetic group that he calls "mechanisms
of mind." Chapter 2, "The Nature of Mind and the MindBody Problem,"
reviews mentalist, dualist, and matenalist theories of the relationship
between mind and body. Franklin explicitly assumes the matenalist position
without proof and seeks thmughout the book to exhibit a wide range of work
that, on the matenalist assumption. is interesting and promising. The reader
is also invited to consider whether the question "Can a computer have
a mind?" might better be phrased. "How much of a mind can a computer
have?" Chapter 3. "Animal Minds," illustrates this continuum
approach by explonog how much mind can be ascnbed to various animals, based
on observations of their behavior.
Franklin organizes thc body of his book around three debates conceming Al.
Chapter 4 is a brief introduction to symbolic Al. Chapter S outlines "The
First Al Debate": whether we can expect computers to think as humans
do. Chapter 6, "Connectionism." shifts the focus from the classic
Al model of mindascomputer to a model that relies on networks of computational
elements that bear some formal resemblance to neurons in the brain. Chapter
7, "The Second Al Debate." reviews arguments between symbolic
Al and connectionists. namely, whether a connectionist approach provides
any capability beyond what can be achieved by direct symbol manipulation.
At the end of these two debates, Franklin is guardedly optimistic about
the possibility of machine minds, and favorably inclined toward connectionist
models.
The next six chapters set the stage for the third Al debate: whether representation
is necessary to implement artificial minds. Chapter 8, "Evolution.
Natural and Artificial.' reviews computer models of natural selection. Chapter
9. "Artificial Life." shows how these algorithms contribute to
the emergence of complexity from a community of individually simple organisms
in Wilson's Animat. Chapter 10. "Multiplicity of Mind," applies
this model to the mind. following suggestions that consciousness emerges
from the interaction of many simple parts. Chapter 11 attempts to answer
the question. "What Do I Do Now?" To decide an organism's next
step, a mind needs access both to external information and to internal memories.
Chapter l2. "What's Out There." expounds Freeman's model of concepts
and argues that ontological categories do not exist absolutely out ;n the
world, but are imposed on the world by the mind. Chapter 13 explains "Remembering
and Creating." Chapter 14. "Representation and the Third Al Debate."
engages the question of whether minds require explicit representations of
concepts. Franklin believes that much situated activity can be done without
representations, but that manipulation of abstract concepts probably requires
them.
Chapter 15, "Into the Future." discusses a few leftover paradigms,
including quantum models of consciousness and
Moravec's bush robot. Chapter 16. "An Emerging New Paradigm of Mind,"
gives Franklin's synthesis, which he teems 'the action selection paradigm
of mind." "Mind" in this sense is the selection of the next
action by an autonomous agent, so any agent that makes such a selection
exhibits some degree of "mind." The mind creates information out
of inputs. rather than processing preexisting concepts. Memories are recreated
from partial clues rather than stored and retrieved as units. The mind is
essentially modular, emerging from the interactions of many simple modules.
Franklin repeatedly emphasizes that he is an amateur leading a tour and
not an expert. As a result. he has achieved a breadth of coverage for which
an expert in a specific discipline could hardly claim credibility. and provides
fellow travelers with a road map of how various approaches relate to one
another and where work remains to be done. This volume will serve students
and researchers alike as an entertaining and accessible pointer to the diversity
of work available on artificial minds. The bibliography contains more than
250 references.
-H. Van Dyke Parunak Ann Arbor, MI