Transitivity
In Piaget's theory of cognitive development, the third stage is called the Concrete Operational Stage. During this stage, which occurs from age 7-12, the child shows increased use of logic or reasoning. One of the important processes that develops is that of Transitivity, which refers to the ability to recognize relationships among various things in a serial order. For example, when told to put away his books according to height, the child recognizes that he starts with placing the tallest one on one end of the bookshelf and the shortest one ends up at the other end.