We summarise and respond to the main points made by, the commentators on ou
r target article, which concern: (1) whether structural similarity can play
a causal role in normal object identification and in neuropsychological de
ficits for living things (2) the nature of our structural knowledge of the
world, (3) the relations between sensory and functional knowledge of object
s, and the nature of our functional knowledge about living things, (4) whet
her we need to posit a "core" semantic system, (5) arguments that can be ma
rshalled from evidence on functional imaging, (6) the causal mechanisms by
which category differences can emerge in object representations, and (7) th
e nature of our knowledge about categories other than living and nonliving
things. We also highlight points raised in our article that seem to be acce
pted.