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1580s, earlier dialatik (late 14c.), from Old French dialectique (12c.), from Latin dialectica, from Greek dialektike (techne) "(art of) philosophical discussion or discourse," fem. of dialektikos "of conversation, discourse," from dialektos "discourse, conversation" (see dialect). Originally synonymous with logic; in modern philosophy refined by Kant, then by Hegel, who made it mean "process of resolving or merging contradictions in character." Related: Dialectics.
originally a form of logical argumentation but now a philosophical concept of evolution applied to diverse fields including thought, nature, and history.