Elroy is horrified by the terrorist acts of september 11, 2001. but while he completely disagrees with the actions of the terrorists, he is able to logically sort how their beliefs led to their behaviors and accurately hypothesize what was probably going through their minds as they carried out their acts. to be able to do this, he would have to be in piaget's

To be able to do this, he would have to be in Piaget's "stage of formal operations".

The formal operational stage is the fourth and last phase of Jean Piaget's theory of cognitive development. It starts at around age 12 and keeps going into adulthood. 
Now being developed, thinking turns out to be substantially more refined and progressed. Children can consider conceptual and hypothetical ideas and utilize rationale to think of innovative answers for issues. Abilities, for example, legitimate idea, deductive thinking, and precise arranging additionally develop amid this stage.

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