The Nicomachean Ethics is the name normally given to Aristotle's best-known work on ethics. The work, which plays a pre-eminent role in defining Aristotelian ethics, consists of ten books, originally separate scrolls, and is understood to be based on notes from his lectures at the Lyceum. The Nicomachean Ethics is widely considered one of the most important historical philosophical works and had an important influence on the European Middle Ages, becoming one of the core works of medieval philosophy. It therefore indirectly became very significant in the development of all modern philosophy as well as European law and theology.