The first two types are not common, for obvious reasons. Brutes are
easy to understand, but their representation generates no inferences.
Given a choice between two possible courses of action, the presence of
a brute makes no difference. So-called Aquinas agents do make a differ-
ence; but then, figuring out what they know would be costly. For every
aspect of every situation, you would have to imagine that the Aquinas
agent represents it, derives conclusions from it, etc. Very few of these
imagined thoughts would be of any consequence. (If a god knows that
my toothpaste contains peroxide, what follows?) This is why, even in
places where the official theology describes an Aquinas agent, people's
actual intuitions do not follow this complicated route, as Barrett and [165]
Keil's experiments showed. I am not suggesting that people could not
entertain the notion of a divine brute or Aquinas agent. I am just saying
that over a huge number of cycles of acquisition and transmission of
cultural material (stories, anecdotes, explanations of events, comments
about situations, etc.) the concepts of full-access strategic agents enjoy
a certain selective advantage, all else being equal, and that this is suffi-
cient to explain why they are more frequently encountered than others.
So what is this cognitive advantage?
It seems, first, that such concepts are relevant because they require
less effort to represent than possible alternatives, given the way our
cognitive systems work. Remember that we always assume that other
people's access to strategic information is imperfect and we therefore
constantly run complicated estimates of what they know, how they
came to know it, what they conclude from it, etc., given the obstacles
between facts and their knowledge of these facts. I talked to so-and-
so yesterday but perhaps you do not know that, because you did not
see the people who saw us together, or you met people who would
not tell you, etc. Conceiving of what the full-access agents know
means running all these estimates minus the obstacles, that is, going
straight from "I met so-and-so" to "The ancestors know that I met
so-and-so."
But there is more. Concepts of full-access agents do not just
require less effort but also generate richer inferences than other super-
natural concepts. To illustrate this, consider the notion, especially
widespread in the United States, that aliens from some remote galax-
ies periodically pay a visit to Earth, contact people, deliver stern warn-
ings to humankind or recruit unwilling participants in bizarre medical
procedures. Anthropologists Charles Ziegler and Benson Saler have
WHYGODS AND SPIRITS?