logikós

Logikós (Greek: λογικός) is an ancient Greek adjective meaning “having reason” or “logical,” and by extension “rational” or “persuasive.” It describes something related to logos, the concept of reason, calculation, or argument, and can denote a person who is capable of sound reasoning or a claim that adheres to logical principles.

Etymology: The term derives from logos (reason, word, principle) with the suffix -ikos, forming Greek adjectives. It is the source of the English words logic and logical, via Latin and other languages. In Modern Greek, logikós means “logical” and logikí means “logic.”

Historical usage: In Classical Greek philosophy, logikós underlies the development of logical theory and dialectic. The related noun logikḗ refers to logic as a discipline. The word appears in discussions of argument structure and evidence-based reasoning, and it contributed to terms such as syllogistikḗ (the study of syllogisms).

Modern usage: In contemporary Greek, logikós remains the standard word for “logical,” while logikí denotes “logic” as a field of study. In English-language philosophy, logikós appears in transliterations of Greek terms and in discussions of Aristotelian logic and the broader history of logic.