In a year after Niebuhr's discovery the whole text of Gaius had been copied out by Goeschen and Hollweg, who had been sent to Verona for that purpose by the Prussian Royal Academy of Sciences, and in 1820 the first edition was published. In 1874 Studemund published an apograph or facsimile volume, the fruits of a new examination of the Veronese MS.; and in 1877 Studemund, with the assistance of Krueger, published a revised text of Gaius founded on the apograph; and I have to acknowledge the courtesy of those distinguished scholars in permitting their text to be printed by the Clarendon Press for the purpose of this edition.
Little is known about Gaius, not even his family name (cognomen), or gentile name (nomen), for Gaius is merely an individual name (praenomen). The word 'Gaius' is a trisyllable in the classical period, for instance, in the versification of Catullus, Martial, and Statius; but at a later period, e. g. in the versification of Ausonius, it is contracted into a dissyllable.
Respecting his date, we know that he flourished under the emperor Hadrian (A.D. 117-189), Antoninus Pius (A.D. 138-161), Marcus Aurelius Antoninus (A.D. 161-180), and Commodus (A.D. 180-192). Gaius himself mentions that he was a contemporary of Hadrian, Dig. 34, 5, 7, pr. He apparently wrote the First Book of his institutions under Antoninus Pius, whom he mentions, § 58, § 74, § 102, without the epithet Divus (of divine or venerable memory), a term only applied to emperor after their decease, but in the Second Book, § 195, with this epithet. The Antoninus mentioned, § 126, is either Pius or Marcus Aureleius Philosophus. Respecting the rules of Cretio, 2 § 177, Gaius appears not to be cognizant of a constitution of Marcus Aurelius mentioned by Ulpian, 22, 34. That he survived to the time of Commodus appears from his having written a treatise on the Sc. Orphitianum, an enactment passed under that emperor.
As the opinions of Gaius are not quoted by the subsequent jurists whose fragments are preserved in the Digest, it has been inferred that Gaius was a public teacher of jurisprudence (jus publice docens), who never in his lifetime obtained the highest distinction of the legal profession, the title of juris auctor (jus publice respondens). Valentinian, however, after his death raised
