Claude Hersault

"The proper things, in the proper manner, in the proper order. God help us all."

- attributed to Hersault

 was an 18th-century occultist and author. He is best known for his books An Introduction to Histories, which describes the five Histories, and The Treatise on Underplaces, which describes the Mansus. He gives his name to Hersault's Nightmare, in which the dreamer hides under floorboards.

Hersault was formerly a pupil of Julian Coseley, but later had an unspecified falling-out with him. He may be the student to whom The Six Letters on Necessity were addressed. According to Teresa Galmier in The Locksmith's Dream: Stolen Reflections, Hersault held that Janus was 'all the Gods'.