Concerning mental development,
Piaget (1969) felt that children from the ages of 3-6 years old
encountered certain limitations that prevented them from having
something called operational thought (the thought needed to operate
effectively in society).
During these years, a child goes through the process of overcoming
these limitations. In particular, the problem that most children
have is their sense of "one-sidedness" or "egocentric"
ways of thinking. They cannot consider two points of view at the
same time (i.e., their own and someone elses) as they consider
the world only from their point of view. For example, children
between these ages have difficulty imagining what an object looks
like from another persons perspective, their conversations are
usually lacking in the information that would help the listener
understand (they assume the listener knows what they know) and
they cannot take the mental perspective of another person.
& Prosocial Behaviour
of Children & Teens