Rationality

Part of speech: noun

Definitions

1. The quality of forming judgments based on logic and reason ; the ability to understand and consider things clearly and sensibly
2. Capacity to think in a coherent, reasonable way without emotional bias ; the skill to analyze situations using clear and sensible thought
3. The trait of applying logical principles and sensible judgment ; the mental faculty that enables clear, rational thinking and decision-making

Etymology: "Rationality" is a plain formation: the adjective "rational" with the suffix "-ity", which turns an adjective into a noun of quality, as in "sanity" from "sane" or "brevity" from "brief". The base goes back to Latin "rationalis", "reasonable", built from "ratio", "reckoning" or "reason", a word rooted in the idea of calculating and counting. The suffix came into English through French "-ité", which itself descends from Latin "-itas". The noun passed through French "rationalité" and Late Latin "rationalitas", which meant "reasonableness" and was already a noun of quality in the late Roman period. English took it from French, so the word carries the older Latin sense of a faculty of reckoning rather than a modern notion of scientific method. Its meaning today, the capacity for clear, unbiased thinking, grows directly from that root.

Synonyms: reasonableness, logic, sanity, judgment, clarity

Antonyms: irrationality, foolishness, insanity