BOOK REVIEW
Dualists from Birth
Ethan Remmel
Descartes' Baby: How the Science of Child Development Explains
What Makes Us Human. Paul Bloom. xvi + 271 pp. Basic Books,
2004. $26.
When I teach about the mind/body issue, I am often struck by how
many of my students are dualists. I'm not talking about modern
hedged positions such as property dualism or explanatory dualism;
I'm talking about good old–fashioned Cartesian substance
dualism, which maintains that our physical bodies/brains are
inhabited by immaterial souls/minds and that body and soul are
intimately linked, yet distinct and dissociable (at death, for
example, when the soul may depart the body). And these students are
not wild–eyed religious evangelists; they are
sober–minded science majors. I pose what seem to me to be
serious problems with this position: For example, how could material
and immaterial substances interact? But many of these students seem
unable even to see the problem. I end up perplexed by their lack of perplexity.
Paul Bloom has an explanation. In his new book, Descartes'
Baby, he maintains that dualism is innate—that is, not
learned. We naturally see the world as containing both material
objects, which are governed by physical laws, and mental entities,
whose behavior is intentional and goal–directed. Some things
in the world, such as people, can be seen either way, as physical
bodies or as intentional agents. However, as Bloom describes, we
tend toward the latter interpretation whenever possible, even
attributing intentions to animated shapes on a computer screen if
they move in certain ways. According to Bloom, dualism is the
product not of nurture but of nature—specifically, evolution
by natural selection. It was adaptive for our ancestors to be able
to predict the behavior of physical objects and social creatures
(especially conspecifics).
This much of Bloom's argument is not new. What is
new—and makes for fascinating reading—is his argument
that many phenomena that we think of as uniquely and essentially
human, such as art, morality, humor and religion, can be explained
as by–products of our innate dualism.
To say that dualism is innate is not to say that it is correct. In
fact, Bloom makes it clear that he is a materialist, not a dualist.
However, he simply states his position without attempting to prove
that materialism is correct—which is probably a good thing,
considering that philosophers have gone around in circles for
centuries on the mind/body issue. Bloom escapes this trap by
changing the question slightly, from whether belief in dualism is
justified to why belief in dualism is so prevalent (the question I
have about my students).
Bloom marshals evidence from cognitive developmental psychology to
show that infants have expectations about the behavior of inanimate
objects that differ from their expectations about the behavior of
animate beings. Furthermore, these expectations appear too early in
life, he argues, to have been learned. The claim that some knowledge
is "built in," however, does not preclude its revision
with age and experience. We are born dualists, but we can learn to
be materialists. Just as training in modern physics may radically
alter our understanding of the physical world, training in modern
cognitive science may lead us to believe that the mind is simply an
emergent property or functional state of the brain. Such beliefs may
be correct, Bloom argues, but they are fundamentally unnatural.
Apparently I'm the one who has the weird ideas, not my dualistic students.

Paul Bloom is an excellent ambassador for cognitive developmental
psychology. He shows how seemingly simple, even trivial, studies
(such as ones that measure how long infants look at one display
versus another) can actually reveal something important about human
nature. He is certainly not the first to claim that children's
cognition is domain–specific. Developmental psychologists such
as Henry Wellman, Susan Gelman, Susan Carey and Alison Gopnik have
described how children use different naive theories to reason about
different types of phenomena (physical vs. psychological vs.
biological). But Bloom is the first to explore the implications of
this insight for a broad range of human characteristics and
activities in a way that is accessible to readers outside the field.
The bulk of Descartes' Baby is an exploration of those
implications for areas as diverse as autism, racism, modern art,
psychopathy, altruism, genocide, disgust, slapstick humor, cloning
and creationism. Some of these sections feel like detours from the
main road of his argument, but they are detours through interesting
terrain with an entertaining guide. Bloom is one of those
frighteningly erudite writers, with an encyclopedic grasp of the
research literature and the ability to throw in the perfect Jorge
Luis Borges quote to illustrate his point. In fact, in his chapter
on art, some of the references may go over the head of the less
well–versed, especially because there are no accompanying illustrations.
Among current popularizers of cognitive psychology, Bloom has no
peer except Steven Pinker. Pinker calls Bloom "the wunderkind
of cognitive science," and their biographies are eerily
similar. Both were born in Montreal (Bloom nine years after Pinker),
both attended McGill University, both did time at MIT (Bloom as a
doctoral student, Pinker as a professor), and both have settled at
the Iviest of the Ivy League schools (Bloom at Yale, Pinker at
Harvard). Both write well, but I found Descartes' Baby to
be an easier read than most of Pinker's books, and it's certainly
shorter (under 300 pages vs. more than 600 for Pinker's How the
Mind Works). But Pinker has much cooler hair.
Descartes' Baby covers a number of different points
relatively quickly—a welcome difference from many academic
books, which tend to dwell on the same point ad infinitum.
Inevitably, in a book of such scope there are a few false notes. For
example, Bloom sets up a dichotomy between naive physics and naive
psychology but is unclear as to whether children's naive biological
concepts fall on one side or the other. He contrasts biological
identity with physical appearance in his discussion of children's
essentialism, but then he contrasts biological functioning with
mental functioning in his discussion of children's beliefs about
death. Many authors consider naive biology to be a separate core
cognitive domain, but Bloom does not mention this possibility.
A few examples fall flat. To illustrate the point that genetic
variability is greater within racial groups than between them, Bloom
makes an analogy between races and families. So far, so good. But
then he asks, rhetorically, "Is my child more genetically
similar to every other Bloom than to every other non–Bloom,
including his mother?" He seems to be saying that the genetic
similarity between child and mother is evidence of similarity
between different groups. In other words, his child's mother is not
a member of the same family because she has a different last name
(Bloom's wife is the developmental psychologist Karen Wynn). I'm not
sure he wants to say this, especially when he goes home.
Nevertheless, a few false notes do not spoil the symphony.
Descartes' Baby incorporates the most recent and
provocative theoretical ideas in cognitive science, such as Simon
Baron–Cohen's hypothesis that people with autism suffer from
"extreme maleness." And Bloom's theoretical points are
leavened with amusing and illuminating anecdotes, such as the story
of the autistic boy who tried to climb him like a ladder to reach a
toy on a high shelf.
Bloom, demonstrating the typical human tendency to interpret the
behavior of others psychologically, initially mistook the contact as
an expression of affection. The boy, however, was demonstrating the
tendency of autistic individuals to view other people as physical
objects rather than as intentional agents. As Bloom notes, "It
would have been simpler if he had just asked me to get him the
toy."—Ethan Remmel, Developmental Psychology,
Western Washington University, Bellingham