It was reported that Mattei began a tradition which later took hold among Italian noblemen and carried on through the 17th century. Upon meeting his social "superior", Cardinal Alessandro Farnese (both were in carriages) in a public street, Mattei ordered his carriage stopped as a mark of respect. The cardinal then ordered his carriage to come alongside Mattei's so that the two could converse. The practice became a standard part of interactions between the various sub-classes of Italian nobility. History of the popes; their church and state (Volume III) by Leopold von Ranke (2009, Wellesley College Library)
