only means that we produce inferences such as "if it is heavy it will
strike hard," "the tail is narrow and therefore affords a good grip"—
that is, our structure-function system is active.
A description of our minds as a bundle of inference systems, differ-
ently activated by different objects, is better than that of a mental
encyclopedia because it is much closer to the way a brain is actually
organized. That is, there is no general "catalogue of all things" in the
brain with their different characteristics; nor is there a division in the
brain between the bits that deal with animals, those that deal with per-
sons, those that only consider artifacts, etc. Instead, there are many
[102] different functional systems that work to produce particular kinds of
inferences about different aspects of our surroundings. This is not just
theoretical speculation: that there are different systems, and that they
are narrow specialists, is made manifest both by neuro-imaging and by
pathology.
Consider for instance the domain of man-made objects. This
would seem to be a straightforward ontological category. Many
objects in our world were made by people and many were not. If our
brain had been designed by philosophers, it would certainly differen-
tiate between man-made and non-man-made stuff in general. But
the brain is subtler than that, because it was designed by evolution.
When people are presented novel artifact-like and animal-like pic-
tures, their brains do show different activation. In the case of arti-
facts, there seems to be enough activity in the pre-motor cortex
(involved in planning movements) to suggest that the system is try-
ing to figure out (forgive the anthropomorphic tone: the system is of
course not aware of what it is doing) some way of handling this new
object. But this only applies if the object is tool-like. In other words,
there may not be a category of "artifacts" in the brain, but there is a
system for "finding out how to handle tool-like objects," which is far
more specific.^4
The specificity is even more obvious in the handling of complex
domains such as animacy and intentionality. In my interpretation of
the story above, I simplified matters a great deal when I said that we
have a system that computes mental states like knowing, hoping, perceiv-
ing, inferring, etc., and produces descriptions of these states in other
people's minds, as an explanation for (and prediction of) their behav-
ior. My description was simplified in that this intuitive psychological
system is in fact composed of a variety of subsystems. The whole scene
with the thief—especially the spectaculardenouement—made sense
RELIGION EXPLAINED