At what stage do individuals begin thinking about multiple variables and formulating hypotheses?

The formal operational stage is characterized by the capacity for abstract thinking and the ability to logically manipulate multiple variables. Individuals in this stage, typically beginning around age 11 and extending into adulthood, can think systematically and consider hypothetical situations. They are able to formulate and test hypotheses, allowing for more sophisticated problem-solving and reasoning skills than in earlier developmental stages.

In contrast, earlier stages, such as the preoperational and concrete operational stages, do not provide the same level of abstract reasoning. During the preoperational stage, children are still primarily focused on concrete experiences and struggle with understanding the perspective of others or considering abstract concepts. The concrete operational stage allows for some logical thinking, but it is largely limited to tangible, concrete situations and specific examples rather than abstract or hypothetical reasoning. The sensorimotor stage, which occurs in the first two years of life, is focused solely on sensory experiences and motor actions, lacking any form of abstract thought or hypothesis generation.

Thus, the ability to think about multiple variables and formulate hypotheses is a hallmark of the formal operational stage of cognitive development.