The makers of fortunes have a second love of money as a creation of their own, resembling the affection of authors for their own poems, or of parents for their children, besides that natural love of it for the sake of use and profit.
Until philosophers rule as kings or those who are now called kings and leading men genuinely and adequately philosophise, that is, until political power and philosophy entirely coincide, while the many natures who at present pursue either one exclusively are forcibly prevented from doing so, cities will have no rest from evils,... nor, I think, will the human race.
For just as poets love their own works, and fathers their own children, in the same way those who have created a fortune value their money, not merely for its uses, like other persons, but because it is their own production. This makes them moreover disagreeable companions, because they will praise nothing but riches.
... for this discovery of yours will create forgetfulness in the learners' souls, because they will not use their memories; they will trust to the external written characters and not remember of themselves.
What the expression is intended to mean, I think, is that there is a better and a worse element in the character of each individual, and that when the naturally better element controls the worse then the man is said to be "master of himself", as a term of praise. But when - as a result of bad upbringing or bad company one s better element is overpowered by the numerical superiority of one s worse impulses, then one is criticized for not being master of oneself and for lack of self control.