Gaius (jurist)

Gaius (/ˈɡeɪəs/; fl. AD 130–180) was a Roman jurist. Little is known about his personal life, including his name (Gaius or Caius being merely his personal name (praenomen)).^[1] It is also difficult to ascertain the span of his life, but it is assumed he lived from AD 110 to at least AD 179, as he wrote on legislation passed within that time.

From internal evidence in his works it may be gathered that he flourished in the reigns of the emperors Hadrian, Antoninus Pius, Marcus Aurelius and Commodus. His works were thus composed between the years 130 and 180. After his death, however, his writings were recognized as of great authority, and the emperor Theodosius II named him in the Law of Citations, along with Papinian, Ulpian, Modestinus and Paulus, as one of the five jurists whose opinions were to be followed by judicial officers in deciding cases. The works of these jurists accordingly became most important sources of Roman law.^[1]

Besides the Institutes, which are a complete exposition of the elements of Roman law, Gaius was the author of treatises on the Edicts of the Magistrates, on the Twelve Tables (Ad Legem XII Tabularum), on the important Lex Papia Poppaea, and on several other topics. His interest in the antiquities of Roman law is apparent, and for this reason his work is most valuable to the historian of early institutions. In the disputes between the two schools of Roman jurists he generally attached himself to that of the Sabinians, who were said to be followers of Ateius Capito, of whose life we have some account in the Annals of Tacitus, and to advocate a strict adherence as far as possible to ancient rules, and to resist innovation. Many quotations from the works of Gaius occur in the Digest, created by Tribonian at the direction of Justinian I, and so acquired a permanent place in the system of Roman law; while a comparison of the Institutes of Justinian with those of Gaius shows that the whole method and arrangement of the later work were copied from that of the earlier, and very numerous passages are word for word the same. The Digest and the Institutes of Justinian are part of the Corpus Juris Civilis. Probably, for the greater part of the period of three centuries which elapsed between Gaius and Justinian, his Institutes had been the familiar textbook for all students of Roman law.^[1]