The best-known work on ethics by Aristotle is The Nicomachean Ethics, as it is known in English. The ten books, which were originally independent scrolls, make up the work, which is said to be based on notes from his Lyceum lectures and is crucial in defining Aristotelian ethics.Aristotle's friend and teacher Plato earlier addressed the Socratic topic of how men should live in his writings as the work's central theme. Many people agree that The Nicomachean Ethics is among the most significant historical philosophical writings. It was a key text of mediaeval philosophy and had a significant influence on the European Middle Ages. As a result, it played a crucial role in the formation of European law and religion as well as all modern philosophy.