If we need to amplify our arguments to arouse our hearers, and if we need to arouse our hearers to win the war of words, we next need to know what specific rhetorical techniques enable this crucial process of amplification to be carried out. It was widely accepted in the first place that a mastery of inventio can help us to stretch the truth in the required ways. As Cicero in particular stresses, we can often invoke a number of loci communes not merely as forms of rhetorical proof but as means of exciting an audience, especially if we draw on such topoi as those which emphasise the weakness of humanity, the fickleness of fortune and so forth. It was also agreed that, in the case of spoken oratory, the element of pronuntiatio can likewise be used to engender powerful emotional effects. On the one hand, as Cicero observes in De partitione oratoria, ‘it is possible to rouse a judge to feelings of hatred merely by adopting a tone of indignant complaint’. And on the other hand, as Quintilian later adds, ‘we can seek to rouse a judge's compassion as well as indignation simply by using a particular modulation of the voice’.

It was generally accepted, however, that the power to amplify, and hence to arouse emotion, depends above all on effective elocutio, and especially on the apt use of ornatus. This is not to say that a desire to excite emotion was taken to be the sole reason for speaking in the Grand Style.