incredulity

Incredulity refers to the state or quality of being unable or unwilling to believe something, or to a reaction of strong disbelief or astonishment. It can describe both a mental stance and an affective response to claims or events, ranging from cautious doubt to outright rejection when evidence is judged insufficient.

The term comes from Latin incredulus, from in- not + credulus trusting; it entered English in the late Middle Ages. It conveys an intensity of disbelief, from mild astonishment to profound refusal to accept a proposition.

In religious contexts, incredulity has been used to describe lack of faith or skepticism toward miracles, as in historical references to the incredulity of Saint Thomas. In literature and rhetoric, incredulity can function as a narrative or argumentative device to test plausibility or to illustrate characters’ reactions to improbable events.

In contemporary discourse, incredulity is a general reaction to sensational or extraordinary claims and can accompany both skepticism and curiosity. Related terms include disbelief, doubt, skepticism, and mistrust; related phrases include the incredulity of the witness or beyond belief. Psychology studies how belief formation is influenced by biases and evidence evaluation, though incredulity itself is a reactive stance rather than a cognitive failure.