Discourses: Book 4 12 : 2

What are the things, then, to which I ought to pay attention?—First, these general principles, and you ought to have them at your command, and without them neither go to sleep, nor rise up, nor drink, nor eat, nor mingle with men; I mean the following: No man is master of another's moral purpose; and: In its sphere alone are to be found one's good and evil. It follows, therefore, that no one has power either to procure me good, or to involve me in evil, but I myself alone have authority over myself in these matters. Accordingly, when these things are secure for me, what excuse have I for being disturbed about things external? What kind of tyrant inspires fear, what kind of disease, or poverty, or obstacle?—But I have not pleased So-and-so.—He is not my function, is he? He is not my judgement, is he?—No.—Why, then, do I care any longer?—But he has the reputation of being somebody.—He and those who think so highly of him will have to see to that, but I have one whom I must please, to whom I must submit, whom I must obey, that is, God, and after Him, myself. God has commended me to myself, and He has subjected to me alone my moral purpose, giving me standards for the correct use of it; and when I follow these standards, I pay heed to none of those who say anything else, I give not a thought to anyone in arguments with equivocal premisses. Why, then, in the more important matters am I annoyed by those who censure me? What is the reason for this perturbation of spirit? Nothing but the fact that in this field I lack training. For, look you, every science is entitled to despise ignorance and ignorant people, and not merely the sciences, but also the arts. Take any cobbler you please, and he laughs the multitude to scorn when it comes to his own work; take any carpenter you please.