At what stage do individuals typically develop the ability for abstract thinking and hypothetical reasoning according to Piaget?

Individuals typically develop the ability for abstract thinking and hypothetical reasoning during the Formal Operational stage, which is the fourth stage in Jean Piaget's theory of cognitive development. This stage generally begins around the age of 12 and continues into adulthood.

In the Formal Operational stage, individuals can think logically about abstract concepts, engage in systematic planning, and consider hypothetical situations. They move beyond concrete reality to reason about possibilities, making it possible to formulate hypotheses and systematically test them. This advanced cognitive ability leads to more complex problem-solving skills, the capacity for moral reasoning, and an ability to think critically.

The previous stages, like the Preoperational stage, focus on symbolic thinking but lack the ability for logical reasoning about abstract concepts. Similarly, the Concrete Operational stage allows for logical thinking but is limited to tangible, concrete information. The notion of "Preoperational Introspection" isn’t a recognized stage in Piaget's framework, so it doesn't align with his theory. Thus, Formal Operational is the correct and appropriate stage where abstract thinking and hypothetical reasoning emerge.