Surprise (emotion)

Surprise is a feeling of shock due to something perceived as unexpected. It is one of the basic emotions. There is pleasant and unpleasant surprise. (TS Eliot said, good poetry was continuous slight surprise. It is probably a misquote since surprise is not continuous but exists in the instant - it may be continual.) There is also non-emotional, intellectual surprise such as, “I was surprised to learn that he had worked on the Manhattan Project."

In information theory, it is customary to refer a measure on events called the self-information of an event, specifically, the logarithm of the reciprocal of the probability of the event, as the surprisal of the events in question.