Evolution and the Human Mind
Full Title: Evolution and the Human Mind: Modularity, Language, and Meta-Cognition
Author / Editor: Peter Carruthers and Andrew Chamberlain (editors)
Publisher: Cambridge University Press, 2000
Review © Metapsychology Vol. 5, No. 42
Reviewer: James Sage
“How did our minds evolve? Can evolutionary considerations illuminate
the question of the basic architecture of the human mind?” These are the
two driving questions behind this new volume edited by Peter Carruthers
and Andrew Chamberlain. This excellent collection of twelve original essays
is the culmination of a two-year series of workshops and a concluding conference
sponsored by Sheffield University’s Hang Seng Centre for Cognitive Studies.
This project is a testament to the value of the interdisciplinary study
of the human mind. By bringing together philosophers, cognitive neuroscientists,
psychologists, cultural anthropologists, archaeologists, and evolutionary
biologists, the result is a unique treatment of contemporary debates regarding
(a) the modularity and innateness of our cognitive faculties, (b) the distinctively
human capacity for natural language, and (c) the evolutionary role of meta-cognition
(cognition about cognition – thoughts about the thoughts of others). These
are among the key debates in the literature.
There are no weak essays in this collection. Each is quite readable,
mildly controversial, and thoroughly provocative. This volume opens with
an invaluable introduction that, in addition to summarizing each chapter,
provides a brilliant “get up to speed” summary of the key developments
in the fields of evolutionary psychology, anthropology, cognitive science,
and philosophy. This introduction allows the non-expert to get a sense
of the underlying context of the debates, and makes the rest of the volume
readable and engaging.
Among the topics addressed, in one way or another, include: the nature
and evolutionary origin of the human mind; the mind’s modularity, structure
and function; evolutionary approaches to psychopathology; the adaptive
origins of language; the archaeology of the mind; the evolution of knowledge;
and the evolutionary basis of consciousness and self-awareness. While my
review cannot fully capture the significance of this volume, it is highly
recommended for anyone remotely interested in the evolution of mind.
Evolutionary psychology
Several chapters address the notion of evolutionary psychology
– or, the evolutionary study of the human mind. This general approach should
be distinguished from the specific research program made popular by Cosmides
and Tooby (see, for example, The
Adapted Mind, edited by Barkow, Cosmides, & Tooby, 1992). I
shall use “Evolutionary Psychology” (capitalized) to refer to the specific
program endorsed by Cosmides and Tooby, and “evolutionary psychology” (lower-case)
to refer to the general approach that merely endorses the evolutionary
study of the human mind. One of the major tenets of evolutionary psychology
is that the mind is composed of discrete mental faculties or modules, each
of which is the adaptive response to a particular challenge presented to
ancestral humans. The human mind, in other words, is constituted by a group
of specialized modules. But just how “modular” is the mind? Is the mind
“massively” modular?
The chapter by Richard Samuels addresses this issue of massively modular
minds. He discusses and clarifies the “Massive Modularity Hypothesis” (MMH)
and concludes that the standard arguments against MMH are in fact quite
weak. As a result, Samuels effectively rebuts many of the poor arguments
against evolutionary psychology (and there are many poor arguments
in the literature). The strength of the contribution by Samuels is that
it works as a corrective measure concerning the debate over the modularity
of the mind by clarifying what it is that proponents of evolutionary psychology
actually claim about the origin and structure of the mind.
The archaeology of the mind
Among the challenges of studying the evolutionary history of mind is
the complete lack of fossilized ancient brains for study – the brains of
our ancestors are simply not preserved. While we may study cranial “endocasts”
(replicas of brains produced by the internal surface of the skull) this
can only tell us about the gross anatomy of early brains. There is little
direct evidence of the neural structure and cortical organization of early
human brains. The chapter by Thomas Wynn introduces some of the techniques
for “cognitive archaeology” (these techniques include a wide range of historical
evidence such as stone tools, cave paintings, and other symbolic expressions).
Wynn focuses on issues of symmetry in order to defend a form of domain-general
account of human cognitive abilities. The presence of symmetry in the archaeological
record suggests that spatial abilities found in modern humans appeared
some 300,000 years ago, and did not require language. From this, Wynn argues
that early hominid cognitive structure included some central domain-general
organization, which employs a more peripheral visual-spatial capacity (which
is itself highly specialized). While the overall conclusion of this chapter
is in some sense ambitious, the attempt to defend a view of the mind as
domain-general is not entirely incompatible with leading proponents of
evolutionary psychology, especially those who reject a strong version of
the Massive Modularity Hypothesis. In other words, even if we grant Wynn
the claim that there are at least some central domain-general cognitive
processes, this by no means refutes the notion that the human mind is largely
constituted by domain-specific modules. It is, however, a valuable addition
to the overall discussion regarding the evolutionary trajectory of mind.
Theory of mind
Speaking of minds, evolutionary psychologists and other scholars studying
the mind from an evolutionary point of view propose specific mental modules,
including a “Theory of Mind Module” (ToMM). Roughly, the idea behind this
module is that early hominids developed specialized “mind reading” abilities
(say, by employing various facial and behavioral cues, eye direction, tone
of voice, etc.) and as a result, we’re able to generate a concept of other
people’s minds, thus allowing us to better predict their behavior (and,
in some cases perhaps, manipulate their behavior to benefit ourselves).
Thus, by emplying a sophisticated concept of other minds, this allows us
to better cope with growing group size, cooperation with others, and the
increased demand on cheat detection.
The chapter by Robin Dunbar explores the adaptive purpose of a ToMM
abilities. Drawing on his previous work linking cognitive development and
group size, Dunbar argues that the demands placed on cognitive sophistication
due to increased group size is what explains the development of various
human cognitive functioning, including the employment of a ToMM. Related
to this, the chapter by Adam Morton focuses on strategic thinking in competitive
and cooperative settings. Morton explores the thorny issue of rationality
(specifically, strategic thinking) in evolutionary contexts. He argues
that the connection between evolutionary pressures in early hominids and
stable strategic thinking yields accurate predications (already found amongst
apes and thought to apply to early hominids) regarding group size and coalition-building
within groups.
Psychopathology
The chapter by Dominic Murphy and Stephen Stich, “Darwin in the Madhouse,”
is an excellent essay touting the strength of evolutionary psychology when
applied to psychopathology. Murphy and Stich present a proposal for the
classification of mental disorders based on the basic tenets of evolutionary
psychology. Specifically, they propose a computational systems approach
in order to provide a diagnosis of mental disorders which allows psychopathologists
to abandon the vague clinical phenomenology characteristic of the Diagnostic
and Statistical Manual of Mental Disorders (DSM). This alternative evolutionary
framework permits classification of psychopathologies based on the underlying
malfunction of cognitive systems. For example, some mental illnesses may
be due to a malfunctioning module, or produced by a properly functioning
module that receives tainted input from other modules further “upstream”.
(Note: the clinical phenomenology found in DSM deals solely with manifestations
of the cognitive system, offering no insight as to the underlying causes
of illness. Hence, use of the DSM fails to penetrate the deeper malfunction
associated with mental illness.) Another way in which an evolutionary framework
identifies mental illness is in terms of a mismatch between mind and world
– our Pleistocene minds are just not equipped to handle many features of
post-industrial society. For example, the fear of heights might well be
a perfectly adaptive response in early human development, but it is debilitating
for those required to work in high-rise office buildings. As such, Murphy
and Stich claim that such “disorders” due to a mismatch between mind and
environment really aren’t mental disorders at all, and this is because
the mind is functioning normally, given the environmental input. Murphy
and Stich are also careful to point out that some of our current classifications
(as per typical psychological DSM diagnoses, such as antisocial behavior)
might not be mental disorders at all. While anti-socials may be problems
for us, their minds are nevertheless functioning exactly as nature intended
(playing the odds, as it were, between manipulating others and maintaining
“sincere” relationships). So, the approach suggested by Murphy and Stich
provides a clear, principled way of distinguishing when someone has a mental
disorders and when someone is simply annoying to the rest of us.
Taken as a whole, this collection of essays is an outstanding contribution
to the evolutionary understanding of mind. It is also a model of successful
interdisciplinary study in what seems to be an ever-specializing academic
environment.
© 2001 James Sage
James
Sage is a graduate student in Philosophy at the University of Utah,
Salt Lake City.
This review first appeared online Sept 1, 2001.
Categories: Philosophical, Genetics
Tags: Neuroscience and Neuropsychology, Science (General)