John watches Mary, who is grasping a flower. John knows what
Mary is doing--she is picking up the flower--and he also knows
why she is doing it. Mary is smiling at John, and he guesses
that she will give him the flower as a present. The simple scene
lasts just moments, and John¿s grasp of what is happening is
nearly instantaneous. But how exactly does he understand Mary's
action, as well as her intention, so effortlessly? A decade ago
most neuroscientists and psychologists would have attributed an
individual's understanding of someone else's actions and,
especially, intentions to a rapid reasoning process not unlike
that used to solve a logical problem: some sophisticated
cognitive apparatus in John¿s brain elaborated on the
information his senses took in and compared it with similar
previously stored experiences, allowing John to arrive at a
conclusion about what Mary was up to and why.