Chapter 5 addresses four more substantial liaisons, all involving ‘window imitation’. Epistles 5.8 (on writing history) works closely with Institutio 10.1, and reaches through it to Thucydides’ preface. Epistles 3.13 (on the style of the Panegyricus) combines Quintilian’s attack on ‘naturalists’ (Institutio 2.11–12) with his remarks on style (Institutio 8.3) and his own point of reference in Cicero’s De oratore. Epistles 4.7 attacks Regulus as immoral orator with help from Institutio 12.5 and its model passage in De oratore. Finally and most curiously, Epistles 2.14 (attacking degenerate advocates and audiences) combines Quintilian on ‘sing-song’ performance (Institutio 11.3) with other passages from the Institutio and Cicero’s Orator in an abstruse display of wit.