‘All human beings, by their nature, desire understanding.’ The first sentence of Aristotle's Metaphysics is paradigmatically true of its author. He sought to understand, and to help others to understand, logic, mathematics, the nature of reality, physics, knowledge, the mind, language, biology, physiology, astronomy, time, theology, literature, rhetoric, the nature of human happiness, and much else. A full translation of his works – of which only one fifth has survived – runs to over one-and-a-half million words.

Aristotle was born in Stagira, in Macedonia (now northern Greece), in 384 bce. His father was a doctor, and this may partly explain his fondness for medical analogies in the Ethics (see, e.g., 1138b). Aristotle arrived in Athens in 367, and spent the next twenty years there as a member of Plato's Academy. Plato died in 347, and Aristotle left Athens for thirteen years, during some of which he was tutor to Alexander. In 334 he founded the Lyceum in Athens, remaining there till shortly before his death in 322.

The Nicomachean Ethics (NE, or the ‘Ethics’) is almost certainly the product of Aristotle's developed intellect, consisting in a revision of around 330 of his earlier Eudemian Ethics (though some scholars believe the Eudemian to be later, and indeed better). NE contains ten books, of which three – books V–VII – are shared with the Eudemian Ethics, and usually thought to belong to that earlier work.