One of the most famous, controversial findings in psychology: 70% of adults don't reach the final stage of Piaget's cognitive development. They cannot fully separate their assumptions from truths, cannot play devil's advocate, struggle to formulate hypotheses, and don't experiment in daily life.

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One of the most famous, controversial findings in psychology: 70% of adults don't reach the final stage of Piaget's cognitive development. They cannot fully separate their assumptions from truths, cannot play devil's advocate, struggle to formulate hypotheses, and don't experiment in daily life.