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God in all his fullness, this in spite of formal logic's indispensable role in understanding. How is
it that the human use of logic can become a barrier to understanding? To help answer this
question we will have to consider how it is that the human use of formal logic develops.
Jean Piaget, the great, Swiss, cognitive-developmental psychologist, devoted his life to
tracking the development of reason over the course of childhood and adolescence into its mature
form in adults. As a result of his studies, Piaget
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found that the ability to think logically
develops over time in fairly discrete stages of increasing complexity,
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with the ability to use
formal logic beginning to develop in adolescence.
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The first stage we could call "preformal" or
"presystemic." (Piaget actually distinguished two childhood stages he called preoperational and
concrete operational. But here we will treat them as one stage.) Presystemic thought is the
thinking of the child (and most adults when we don't need or want to think more complexly
about a topic). School-age children have a limited ability to think logically. For example, they
can draw inferences regarding material reality (the size and shape of objects) and relationships
between objects (stick A > stick B, stick B > stick C, so stick A > stick C). However,
preadolescents cannot think abstractly; they cannot think about their thoughts, they cannot relate
thoughts to each other and assess their logical consistency, and they cannot organize their
thoughts into a coherent system. Rather, their belief system contains internal contradictions,
which they are unable to recognize, because they have not developed the cognitive ability to
identify immaterial objects (like thoughts).
Piaget found that adolescents begin to develop the ability to think abstractly or
systemically--what he called the stage of "formal operations." They can think about their
thoughts (second-order mental operations), so they can organize and compare those thoughts,