Quomodo historia conscribenda sit

If a person has to be introduced to make a speech, above all let his language suit his person and his subject, and next let these also be as clear as possible. It is then, however, that you can play the orator and show your eloquence.

Eulogy and censure will be careful and considered, free from slander, supported by evidence, cursory, and not inopportune, for those involved are not in court, and you will receive the same censure as Theopompus, who impeached nearly everybody in a quarrelsome spirit and made a business of it, to the extent that he was a prosecutor rather than a recorder of events.

Again, if a myth comes along you must tell it but not believe it entirely; no, make it known for your audience to make of it what they will—you run no risk and lean to neither side.