Institutio Oratoria

Finally, they urge that all the earliest orators spoke according to the dictates of nature, but that subsequently there arose a class of speakers resembling poets rather than orators, who regarded false and artificial methods of expression as positive merits; they were, it is true, more sparing than the poets in their use of such expressions, but none the less worked on similar lines. There is some truth in this contention, and we should therefore be careful not to depart from the more exact usage of ordinary speech to the extent that is done by certain orators.