What is the primary assertion of Aristotles Nicomachean Ethics?

The primary assertion of Aristotle's Nicomachean Ethics is that the ultimate goal of human life is to achieve eudaimonia, which is often translated as "happiness" or "flourishing." This is achieved through virtuous living and the cultivation of moral character. Aristotle argues that virtues lie in finding the mean between two extremes of behavior, known as the doctrine of the golden mean.