credulus

Credulus is a Latin adjective meaning believing, credulous, or trusting. In classical Latin it described a person inclined to believe readily or without sufficient evidence. The term is the source of the English adjective credulous and of the noun credulity, both sharing the sense of a readiness to believe.

Etymology and grammar: Credulus comes from the verb credere, “to believe,” with the common Latin suffix -ulus forming an adjective. It belongs to the second-declension class of adjectives and has the regular endings credulus (masculine), credula (feminine), and credulum (neuter). In use, it can modify a noun directly (vir credulus, “a credulous man”) or appear predicatively (puer est credulus, “the boy is credulous”).

Usage and cognates: In English, credulus yields credulous, with its related noun credulity to denote the tendency to believe without sufficient evidence. In Romance languages, descendants include Spanish crédulo/creíble and credulidad, Italian credulo/credulezza, and Portuguese crédulo/credulidade, all retaining the core meaning of readiness to believe. The term is often discussed in contexts related to belief, skepticism, and critical thinking, where credulity denotes a tendency to accept statements too readily.

See also: Credo, from the verb credo “I believe,” shares the broader semantic field of belief. Credulity and related terms appear in philosophy and psychology when examining justification, evidence, and trust.

Note: While credulus is primarily a Latin descriptive term, its influence persists in modern languages through related words referring to belief and gullibility.