The Divine Institutes

To this is added, that it is not uniform; but being divided into sects, and scattered into many and discordant opinions, it has no fixed state. For since they all separately attack and harass one another, and there is none of them which is not condemned of folly in the judgment of the rest, while the members are plainly at variance with one another, the whole body of philosophy is brought to destruction. Hence the Academy afterwards originated. For when the leading men of that sect saw that philosophy was altogether overthrown by philosophers mutually opposing each other, they undertook war against all, that they might destroy all the arguments of all; while they themselves assert nothing except one thing—that nothing can be known. Thus, having taken away knowledge, they overthrew the ancient philosophy. But they did not even themselves retain the name of philosophers, since they admitted their ignorance, because to be ignorant of all things is not only not the part of a philosopher, but not even of a man. Thus the philosophers, because they have no defence, must destroy one another with mutual wounds, and philosophy itself must altogether consume and put an end to itself by its own arms. But they say it is only natural philosophy which thus gives way. How is it with moral? Does that rest on any firm foundation? Let us see whether philosophers are agreed in this part at any rate, which relates to the condition of life.