Conflicts over the censorship of humor go back at least to the fifth century B.C.E., when Plato expressed the idea in his Republic that jokes and humorous incidents should be removed from stories about the gods before they are presented to young people. Plato's idea was that if children were amused by the gods, they would feel themselves superior and hence would lose respect.
Several centuries later the English philosopher Thomas Hobbes spelled out more clearly the idea that humor is an expression of superiority. In his 1651 Leviathan, he defined humor as "the sudden glory arising from the sudden conception of some eminency in ourselves, by comparison with the infirmity of others." In the seventeenth century Blaise Pascal, a French scientist and philosopher, proposed, "Nothing produces laughter more than a surprising disproportion between that which one expects and that which one sees." In 1750 the Scottish philosopher Frances Hutcheson further developed what has come to be known as the incongruity theory. In his Reflections upon Laughter, Hutcheson pointed out that people do not go to asylums to laugh at the "inferior" beings, nor do they laugh at animals except when they resemble human beings. Even when someone slips on a banana peel, observers laugh not because they feel superior but because of the incongruity between expectations and reality.