[Side-note: Correction by Thrasymachus--if the Ruler mistakes, he is _pro tanto_ no Ruler--The Ruler, _quâ_ Ruler--_quâ_ Craftsman--is infallible.] Thrasymachus might have replied to this objection by saying, that he meant what the superior power conceived to be for its own advantage, and enacted accordingly, whether such conception was correct or erroneous. This interpretation, though indicated by a remark put into the mouth of Kleitophon, is not farther pursued.[18] But in the reply really ascribed to Thrasymachus, he is made to retract what he had just before admitted--that the superior authority sometimes commits mistakes. In so far as a superior or a ruler makes mistakes (Thrasymachus says), he is not a superior. We say, indeed, speaking loosely, that the ruler falls into error, just as we say that the physician or the steersman falls into error. The physician does not err _quâ_ physician, nor the steersman _quâ_ steersman. No craftsman errs _quâ_ craftsman. If he errs, it is not from his craft, but from want of knowledge: that is, from want of craft.[19] What the ruler, as such, declares to be best for himself, and therefore enacts, is always really best for himself: this is justice for the persons under his rule. [Footnote 18: Plato, Republic, i. p. 340 B.] [Footnote 19: Plato, Republic, i. p. 340 E. [Greek: e)pilipou/sês ga\r e)pistê/mês o( a(marta/nôn a(marta/nei, e)n ô(=| ou)/k e)sti dêmiourgo/s; ô(/ste dêmiourgo\s ê)\ sopho\s ê)\ a)/rchôn ou)dei\s a(marta/nei to/te o(/tan a)/rchôn ê)=|.]] [Side-note: Reply by Sokrates--The Ruler, _quâ_ infallible Craftsman, studies the interest of those whom he governs, and not his own interest.] To this subtle distinction, Sokrates replies by saying (in substance), "If you take the craftsman in this strict meaning, as representing the abstraction Craft, it is not true that his proceedings are directed towards his own interest or advantage. What he studies is, the advantage of his subjects or clients, not his own. The physician, as such, has it in view to cure his patients: the steersman, to bring his passengers safely to harbour: the ruler, so far forth as craftsman, makes laws for the benefit of his subjects, and not for his own. If obedience to these laws constitutes justice, therefore, it is not true that justice consists in what is advantageous to the superior or governing power. It would rather consist in what is advantageous to the governed."[20] [Footnote 20: Plato, Republic, i. p. 342.] [Side-note: Thrasymachus denies this--Justice is the good of another. The just many are worse off than the unjust One, and are forced to submit to his superior strength.]