[187]
I say to them that if they are to excel in oratory or in managing affairs or in any line of work, they must, first of all, have a natural aptitude for that which they have elected to do; secondly, they must submit to training and master the knowledge of their particular subject, whatever it may be in each case; and, finally, they must become versed and practised in the use and application of their art; for only on these conditions can they become fully competent and pre-eminent in any line of endeavor.