Nicomachean Ethics

...to follow authority in this regard. For Nicomachus is not said to have been of such great learning that he could have composed such a book, which seems rather to be equal to his father’s powers. Moreover, the order of this teaching, if it be compared to other sciences and faculties, as we have received from the Peripatetics and Platonists, seems to be as follows: for after grammar and rhetoric, if we wish to ascend to Philosophy, labor must be given to the art of disputation, which is called Logic; then moral philosophy is immediately to be perceived, so that by its doctrine, as by a kind of cultivation, the mind—with vices torn out by the roots and desires repressed—may be left free, not only for always acting according to right reason, but also fit for speculating and contemplating. Furthermore, if active philosophy is ordered toward the speculative, as they say, undoubtedly moral philosophy itself ought to precede any speculative science; whence it follows that after the doctrine of arguing and disputing, which seems to precede both parts of philosophy like a certain path, this faculty is to be embraced by us, if we wish to preserve perfectly the order of the sciences. Once this has been grasped and perceived, the doctrine of Economics and then finally that of Politics itself is to be taken up. For just as the book of the Physics is to the remaining books of natural philosophy, so moral doctrine seems to be to the remaining parts of active philosophy, for it contains the first elements and the first principles. Therefore, the moral discipline precedes in order; then follow the economic and finally the civil disciplines; and once those things which comprise active philosophy are known, one approaches by degrees thereafter to the speculative itself. A summary division of the Ethics. This work, however, is divided into ten books, as is clearly evident; but what is contained in each book, we shall see more conveniently in other places. Yet we can say most briefly that in the first book the Philosopher proposes to us the ultimate human end...