Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
They will perhaps produce a long list of orators who are most effective in the courts but have never sat under a geometrician and whose understanding of music is confined to the pleasure which their ears, like those of other men, derive from it. To such critics I reply, and Cicero frequently makes the same remark in his Orator, that I am not describing any orator who actually exists or has existed, but have in my mind's eye an ideal orator, perfect down to the smallest detail.
For when the philosophers describe the ideal sage who is to be consummate in all knowledge and a very god incarnate, as they say, they would have him receive instruction not merely in the knowledge of things human and divine, but would also lead him through a course of subjects, which in themselves are comparatively trivial, as for instance the elaborate subtleties of formal logic: not that acquaintance
horn[*]( You have what you have not lost: you have not lost horns: therefore you have horns. ) or
crocodile[*]( A crocodile, having seized a woman's son, said that he would restore him, if she would tell him the truth. She replied, You will not restore him. Was it the crocodile's duty to give him up? ) problems can make a man wise, but because it is important that he should never trip even in the smallest trifles.