Italian poet Dante Alighieri’s description of Aristotle as “the master of those who know” has an appropriate ambiguity: It suggests Aristotle’s mastery of his predecessors’ knowledge and also his influence, paralleled only by Plato’s, on his philosophical descendants. Both aspects of this mastery are prominent in Nicomachean Ethics. It is to Aristotle’s credit that he gives full recognition to the contributions of other philosophers, and it is to his glory that so many basic ethical ideas of later philosophers are found in this great seminal work. Although scholarly explanations of the work differ, it is generally agreed that the work was not intended for publication in its present form; it is a version of Aristotle’s ethics as stated by his son, Nicomachus. The Eudemian Ethics, a record composed by one of Aristotle’s pupils, Eudemus, supplements this work.
Nicomachean Ethics is part of a vast scientific and philosophical system to which a teleological view of the universe is basic: All things are to be understood in terms of their purposes, the ends toward which they tend and which are inherent in their forms and integral to their natures. Defining the end or good of humanity by reference to its nature, Aristotle’s ethics is a kind of naturalism, but not a reductionism failing to distinguish a higher sense of “nature” from one meaning simply “whatever is or occurs.” It thus suggests (though it does not fully develop) the crucial difference between the factual and the ideal. The normative element, the “oughtness,” of virtue is determined by the end or good by which virtue is understood. There is thus no nonnatural, self-subsistent, or supernatural source of obligation, but this is no loss to an ethics grounded firmly in the Aristotelian psychology and metaphysics.