Clichés, stock phrases, adherence to conventional, standardized codes of expression and conduct have the socially recognized function of protecting us against reality, that is, against the claim on our thinking attention that all events and facts make by virtue of their existence.

Hannah Arendt (1906-1975) German-American philosopher, political theorist

Lecture (1971), “Thinking and Moral Considerations,” Social Research (1971 Fall)
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Referring to Adolf Eichmann's use of "cliché-ridden language" as a sign of his "thoughtlessness."

Collected in The Life of the Mind, Part 1 "Thinking," Introduction (1974).