wrongly. Rather, the principle seems to be: if someone has been in percep-
tual contact with the object, then they know everything which I know.
(Perner, 1991, calls this a ‘copy-theory of belief’, since the idea seems to be
that perception gives you a copy of the object as a whole, irrespective of
which properties of it were available to you through perception.) This
principle, while false, is close enough to being true, in most cases which
matter, to be worth having – and certainly it is better than making no
allowance for perceptual contact at all.
ThenWnally, during the fourth year of life, children attain a mature
belief–desire psychology, or what Perner (1991) calls ‘a representational
theory of mind’. (This is not to say that there is no further development
thereafter, of course – on the contrary, the theory continues to be elabor-
ated, becoming considerably more subtle and sophisticated without alter-
ing its fundamentals.) At this stage children come to understand that
people may have beliefs which are false, whichmisrepresenttheir environ-
ment. And they come to work with a distinction between appearance and
reality, understanding that perception presents us with a subjective ap-
pearance of the world, which may sometimes be illusory. We shall return to
consider in much more detail the tests for belief–desire psychology devised
by developmental psychologists in section 4.1 below.
1.2 Simulation-theorySimulationism challenges the above views by proposing that our mind-
reading ability depends upon a process of simulation, rather than on the
deployment of theoretical knowledge. Roughly, the idea is that we can
pretend or imagine ourselves to be situated and motivated in just the way
that other people are, and then go on to reason for ourselves within that
perspective to see how we might then think, feel, and react. We then project
our thoughts, feelings, and decisions onto the targets of our simulations.
Simulation-theory might appear to be made plausible by the fact that we
can, of course, quite consciously and deliberately adopt the strategy of
supposing ourselves in the situation of others – or even, more dramatically,
of re-enacting some episode in their lives – in order to help us anticipate
their actions and/or appreciate their responses. But these are rather excep-
tional procedures, and simulationism needs a more low-key general ac-
count of simulation in order to deal with the mainly mundane business of
mind-reading.
The leading advocates of simulationism have been the philosophers
Gordon (1986, 1992, 1995) and Goldman (1989, 1992, 1993), and the
psychologist Harris (1989, 1991, 1992). Like theory-theory, simulation-
theory can take on a range of variations. One way in which simulationism
80 Mind-reading