Ratiocination

Reason is the capacity for consciously making sense of things, applying logic, establishing and verifying facts, and changing or justifying practices, institutions, and beliefs based on new or existing information. It is closely associated with such characteristically human activities as philosophy, science, language, mathematics, and art and is normally considered to be a definitive characteristic of human nature. Reason, or an aspect of it, is sometimes referred to as rationality.

Reasoning is associated with thinking, cognition, and intellect. Reasoning may be subdivided into forms of logical reasoning (forms associated with the strict sense): deductive reasoning, inductive reasoning, abductive reasoning; and other modes of reasoning considered more informal, such as intuitive reasoning and verbal reasoning. Along these lines, a distinction is often drawn between discursive reason, reason proper, and intuitive reason, in which the reasoning process—however valid—tends toward the personal and the opaque. Although in many social and political settings logical and intuitive modes of reason may clash, in other contexts intuition and formal reason are seen as complementary, rather than adversarial as, for example, in mathematics, where intuition is often a necessary building block in the creative process of achieving the hardest form of reason, a formal proof.

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Wikipedia