Abel Hendy Jones Greenidge, 1911 Encyclopædia Britannica (1911)
“ Since the theory of the persistence of the republican constitution was of the essence of the Principate, the consuls necessarily lost little of their outward position and dignity under the rule of the Caesars. The consulship was the only office in which a citizen, other than a member of the imperial house, might have the princeps as a colleague, and in the interval between the death or deposition of one princeps and the appointment of another the consuls resumed their normal position as the heads of the state (cf. Herodian ii. 12) . ”
