Institutio Oratoria

Some say that political questions provide the material. The mistake made by these lies not in the quality of their opinion but in its limitation. For political questions are material for eloquence but not the only material.

Some, on the ground that rhetoric is a virtue, make the material with which it deals to be the whole of life. Others, on the ground that life regarded as a whole does not provide material for every virtue, since most of them are concerned only with departments of life (justice, courage and self-control each having their own duties and their own end), would consequently restrict oratory to one particular department of life and place it in the practical or pragmatic department of ethics, that is to say the department of morals which deals with the business of life.