why computer programs have great difficulty recognizing a circle and
a square in the above figures. It takes quite a lot of subtle program-
ming to circumvent this rigidity. Humans, in contrast, spontaneously
think of such cases as a combination of (1) an instance of the usual
concept and (2) a minor change added to it, that only affects some of
its properties. This is also the way that supernatural concepts are built:
by using default expectations from ontological categories.
This is important because it explains an aspect of cultural transmis-
sion that would otherwise remain mysterious—namely, that in the
domain of the supernatural, people have detailed representations even
though they are not told much. Take the example of our familiar ghosts [75]
again. You were probably told at some point that ghosts can walk
through walls. Similarly, the Fang are told that ghosts often appear in
clearings in the forest, out of nowhere, and then disappear in the same
counterintuitive way. But neither you nor the Fang were ever told that
"ghosts can see what happens when it happens" or that "ghosts
remember what has happened after it has happened." No one ever
says that, because no one needs to say it. These inferences that literally
go without saying are spontaneously produced because our minds
apply a default principle.
In this domain, then, cultural transmission is very easy because the
mind provides a lot of information to complete the fragmentary ele-
ments provided by other people. It is not too surprising that various
people have similar representations about the ghosts' thought processes,
although no one ever talks about it. The representations are similar
because the PERSON template in everybody's mind is very similar. Cul-
tural transmission is cheap; it does not require much effort at communi-
cation, as long as templates in our mind provide order for free.
WHAT IS INTUITIVE IN THE PARANORMAL
Many people think that, in some circumstances at least, perception
can extend beyond its ordinary limits. One can then guess other peo-
ple's thoughts, visualize events before they actually occur, receive
messages from dead people, travel through time, and so on. In some
form or other, such notions exist the world over. Many people like-
wise have the symmetrical belief that mere thoughts can cause real
effects. Some psychics are said to move objects at a distance or to
make them disappear by sheer willpower.
WHATSUPERNATURALCONCEPTSARELIKE