All human activities aim at some end that we consider good. Most activities are a means to a higher end. The highest human good, then, is that activity that is an end in itself. That good is happiness. When we aim at happiness, we do so for its own sake, not because happiness helps us realize some other end. The goal of the Ethics is to determine how best to achieve happiness. This study is necessarily imprecise, since so much depends on particular circumstances Это и многое другое вы найдете в книге Nicomachean Ethics (Аристотель)