Discourses: Book 1 4 : 3
Do you yourself show me, therefore, your own progress in matters like the following. Suppose, for example, that in talking to an athlete I said, "Show me your shoulders," and then he answered, "Look at my jumping-weights." Go to, you and your jumping-weights! What I want to see is the effect of the jumping-weights. "Take the treatise Upon Choice and see how I have mastered it." It is not that I am looking into, you slave, but how you act in your choices and refusals, your desires and aversions, how you go at things, and apply yourself to them, and prepare yourself, whether you are acting in harmony with nature therein, or out of harmony with it. For if you are acting in harmony, show me that, and I will tell you that you are making progress; but if out of harmony, begone, and do not confine yourself to expounding your books, but go and write some of the same kind yourself. And what will you gain thereby? Do you not know that the whole book costs only five denarii? Is the expounder of it, then, think you, worth more than five denarii? And so never look for your work in one place and your progress in another.