The formula cognomen + nomen, as portrayed in Latronis enim Porcii (Sen. Controv. 1 praef. 13), the first double-name reference without praenomen in Seneca the Elder's work (henceforth referred to simply as Seneca), emerged as a result of the radical changes which the Roman onomastic system began to experience at the end of the Republic. On account of a wide variety of factors, both social and linguistic, the cognomen seized the role of diacritic name and individual signifier, having ousted praenomen from its ancient throne; the relatively limited number of praenomina in common use contributed substantially to their waning. The formulae of two constituents visibly reflected the progressive decline of praenomina; during the Early Principate double names still represented the usual formal means of reference (tria nomina being highly formal, mostly occurring in official contexts), but it mostly consisted of nomen + cognomen rather than praenomen + nomen or praenomen + cognomen. The formula nomen + cognomen, which developed once personal cognomina began to spread among the lesser classes, was primarily crafted for addressing men of ambiguous status, peregrini and freedmen. Thus, Cicero tends to avoid its use in naming members of the nobility, whom he refers to with a clear preference for the older, lustrous conjunction praenomen + cognomen.