noun

rationality

rash-uh-NAL-uh-tee/ˌræʃəˈnæləti/

The quality of being based on reason and logic.

The comparison of measured evidence shows rationality in forming a judgment.

A thoughtful person compares measured evidence using a clear balance and simple records, reason-guided judgment.

Etymology

rationLatinreckoning, calculation, reason

+alLatinpertaining to

+ityLatinquality or state

Latin ratio covered both calculation and reason. Rationality names the quality of possessing reason or agreeing with it, connecting the ability to think logically with being guided by that thinking.

In context

Essential Truth3:06

your abstractions should be independent of your subjectivity and rationality and emotion are construed in that manner as enemies

Jordan Peterson: The Id, Ego, and Superego

More examples

Her explanation convinces me of the plan's rationality.
The debate loses all rationality when personal insults begin.
He values rationality over emotion when making financial decisions.

Forms

rationality

rational adjective — Based on clear reason and sound logic.

rationally adverb — In a way guided by reason.

Similar words

reasonableness: Emphasizes sensible judgment and fairness rather than strict logic.
logic: Refers to sound reasoning itself rather than the quality of reasonableness.