Nothing in oratory is more important than to win for the orator the favour of his hearer, and to have the latter so affected as to be swayed by something resembling an impulse of the spirit impetu quodam animi or emotion perturbatione, rather than by judgment or deliberation. For men decide far more problems by hate, or love, or lust, or rage, or sorrow, or joy, or hope, or fear, or illusion, or some other inward emotion aliqua permotione mentis, than by reality or authority, or any legal standard, or judicial precedent or statute.
That man is guilty of impertinence who considers not the circumstances of time, or engrosses the conversation, or makes himself the subject of his discourse, or pays no regard to the company he is in.
Everything that thou reprovest in another, thou must most carefully avoid in thyself.
[Lat., Omnia quae vindicaris in altero, tibi ipsi vehementer fugienda sunt.]