It is no common (easy) thing to do this only: to fulfil the promise of a man’s nature. For what is a man? The answer is: a rational and mortal being. Then by the rational faculty from whom are we separated? From wild beasts. And from what others? From sheep and like animals. Take care then to do nothing like a wild beast⁠—but if you do, you have lost the character of a man; you have not fulfilled your promise. See that you do nothing like a sheep⁠—but if you do, in this case also the man is lost. What then do we do as sheep? When we act gluttonously, when we act lewdly, when we act rashly, filthily, inconsiderately, to what have we declined? To sheep. What have we lost? The rational faculty. When we act contentiously and harmfully and passionately and violently, to what have we declined? To wild beasts. Consequently some of us are great wild beasts, and others little beasts, of a bad disposition and small, whence we may say, “Let me be eaten by a lion.” But in all these ways the promise of a man acting as a man is destroyed. For when is a conjunctive (complex) proposition maintained? When it fulfils what its nature promises; so that the preservation of a complex proposition is when it is a conjunction of truths. When is a disjunctive maintained? When it fulfils what it promises. When are flutes, a lyre, a horse, a dog, preserved? (When they severally keep their promise.) What is the wonder then if man also in like manner is preserved, and in like manner is lost? Each man is improved and preserved by corresponding acts: the carpenter by acts of carpentry, the grammarian by acts of grammar. But if a man accustoms himself to write ungrammatically, of necessity his art will be corrupted and destroyed. Thus modest actions preserve the modest man, and immodest actions destroy him; and actions of fidelity preserve the faithful man, and the contrary actions destroy him. And on the other hand contrary actions strengthen contrary characters: shamelessness strengthens the shameless man, faithlessness the faithless man, abusive words the abusive man, anger the man of an angry temper, and unequal receiving and giving make the avaricious man more avaricious.

For this reason philosophers admonish us not to be satisfied with learning only, but also to add study, and then practice. For we have long been accustomed to do contrary things, and we put in practice opinions which are contrary to true opinions. If then we shall not also put in practice right opinions, we shall be nothing more than the expositors of the opinions of others. For now who among us is not able to discourse according to the rules of art about good and evil things (in this fashion)? That of things some are good, and some are bad, and some are indifferent: the good then are virtues, and the things which participate in virtues; and the bad are the contrary; and the indifferent are wealth, health, reputation.⁠—Then, if in the midst of our talk there should happen some greater noise than usual, or some of those who are present should laugh at us, we are disturbed. Philosopher, where are the things which you were talking about? Whence did you produce and utter them. From the lips, and thence only. Why then do you corrupt the aids provided by others? Why do you treat the weightiest matters as if you were playing a game of dice? For it is one thing to lay up bread and wine as in a storehouse, and another thing to eat. That which has been eaten, is digested, distributed, and is become sinews, flesh, bones, blood, healthy color, healthy breath. Whatever is stored up, when you choose you can readily take and show it; but you have no other advantage from it except so far as to appear to possess it. For what is the difference between explaining these doctrines and those of men who have different opinions? Sit down now and explain according to the rules of art the opinions of Epicurus, and perhaps you will explain his opinions in a more useful manner than Epicurus himself. Why then do you call yourself a Stoic? Why do you deceive the many? Why do you act the part of a Jew, when you are a Greek? Do you not see how (why) each is called a Jew, or a Syrian or an Egyptian? and when we see a man inclining to two sides, we are accustomed to say, “This man is not a Jew, but he acts as one.” But when he has assumed the affects of one who has been imbued with Jewish doctrine and has adopted that sect, then he is in fact and he is named a Jew. Thus we too being falsely imbued (baptized), are in name Jews, but in fact we are something else. Our affects (feelings) are inconsistent with our words; we are far from practicing what we say, and that of which we are proud, as if we knew it. Thus being unable to fulfil even what the character of a man promises, we even add to it the profession of a philosopher, which is as heavy a burden, as if a man who is unable to bear ten pounds should attempt to raise the stone which Ajax lifted.