Whether intentionally or unintentionally, previously published works have neglected ancient Graeco-Roman texts that either cause horror or may be said to belong to the horror genre. This may be the result of the low esteem in which any text that did not fit neatly into one of the major and traditional literary genres was held by most scholars--particularly apparent concerning texts that dealt with the supernatural or the occult, which were often relegated to specialists in ancient religions, rituals, or beliefs. Horror in Classical Literature: "On a Profound and Elementary Principle" serves as a good introduction to horror in ancient Graeco-Roman literature. It reviews the concepts of horror (literary, psychological, and biophysical), examines the current definitions for horror fiction, evaluates the current interest in the darker side of the classical world, and suggests new ways of thinking about horror as a genre.