The answer to this question is
Conservation.
Conservation in psychology means the
ability to know that even you change the size or shape of a container the
mixture inside it still have the same volume. Conservation is the theory of the
psychologist Jean Piaget. The lack of conservation in kids is always been
observed when kids chooses the tallest glass of juice because they thought that
it has more juice even if the glass is the thinnest from the glasses.
