In recent years a number of studies have detailed young children's enr
iched, domain-specific, and theory-like understanding in several cogni
tive domains, including naive biology, naive psychology, and reasoning
about physical objects. With few exceptions, students of cognition ha
ve not considered the possibility that the acquisition and representat
ion of social categories may also be governed by a specialized faculty
for understanding. Rather, most accounts of children's social categor
ization assume that the classification of the human realm is derived f
rom observations of superficial differences in appearance and does not
include expectations of deeper commonalities among category members.
Five experiments are reported that challenge this view. The results in
dicate that young children's inferences about human racial variation i
nvolve domain-specific reasoning that parallels but is distinct from c
ommon sense understanding of naive biology. These findings have implic
ations for our understanding of the transfer of knowledge across domai
ns and for determining the appropriate level of description of domain-
specific devices.