8 June 2013 | NewScientist | 33of events described earlier, only with puppets
and a missing ball (see diagram, page 34).
When asked, “When Sally returns, where
will she look for the ball?”, most 3-year-olds
say with confidence that she’ll look in the
new spot, where Anne has placed it. The
child knows the ball’s location, so they
cannot conceive that Sally would think it
was anywhere else.Baby change
But around the age of 4, that changes. Most
4 and 5-year olds realise that Sally will expect
the ball to be just where she left it.
For over two decades that was the dogma,
but more recently those ideas have been
shaken. The first challenge came in 2005,
when it was reported in Science (vol 308, p 255)
that theory of mind seemed to be present in
babies just 15 months old.
Such young children cannot answer
questions about where they expect Sally to
look for the ball, but you can tell what they’re
thinking by having Sally look in differentplaces and noting how long they stare: babies
look for longer at things they find surprising.
When Sally searched for a toy in a place she
should not have expected to find it, the babies
did stare for longer. In other words, babies
barely past their first birthdays seemed to
understand that people can have false beliefs.
More remarkable still, similar findings were
reported in 2010 for 7-month-old infants
(Science, vol 330, p 1830).
Some say that since theory of mind seems
to be present in infants, it must be present in
young children as well. Something about the
design of the classic Sally-Anne test, these
critics argue, must be confusing 3-year-olds.
Yet there’s another possibility: perhaps we
gain theory of mind twice. From a very young
age we possess a basic, or implicit, form of
mentalising, so this theory goes, and then
around age 4, we develop a more sophisticated
version. The implicit system is automatic but
limited in its scope; the explicit system, which
allows for a more refined understanding of
other people’s mental states, is what you need
to pass the Sally-Anne test. >us predict other people’s behaviour, tell lies,
and spot deceit by others. Theory of mind is a
necessary ingredient in the arts and religion –
after all, a belief in the spirit world requires us
to conceive of minds that aren’t present – and
it may even determine the number of friends
we have.
Yet our understanding of this crucial
aspect of our social intelligence is in flux.
New ways of investigating and analysing it
are challenging some long-held beliefs. As
the dust settles, we are getting glimpses of
how this ability develops, and why some of
us are better at it than others. Theory of mind
has “enormous cultural implications”, says
Robin Dunbar, an evolutionary anthropologist
at the University of Oxford. “It allows you to
look beyond the world as we physically see it,
and imagine how it might be different.”
The first ideas about theory of mind
emerged in the 1970s, when it was discovered
that at around the age of 4, children make a
dramatic cognitive leap. The standard way to
test a child’s theory of mind is called the Sally-
Anne test, and it involves acting out the chain130608_F_Mindreading.indd 33 31/5/13 14:23:55