X[10arg] The derivation of soror, according to Antistins Labeo, and that of frater, according to Publius Nigidius.
ANTISTIUS LABEO cultivated the study of civil law with special interest, and gave advice publicly to those who consulted him on legal questions; he was also not unacquainted with the other liberal arts, and he had delved deep into grammar and dialectics, as well as into the earlier and more recondite literature. He had also become versed in the origin and formation of Latin words, and applied that knowledge in particular to solving many knotty points of law. In fact, after his death works of his were published, [p. 437] which are entitled Posteriores, of which three successive books, the thirty-eighth, thirty-ninth and fortieth, are full of information of that kind, tending to explain and illustrate the Latin language. Moreover, in the books which he wrote On the Praetor's Edict he has included many observations, some of which are graceful and clever. Of such a kind is this, which we find written in the fourth book On the Edict: 1 “A soror, or 'sister,'” he says, “is so called because she is, as it were, born seorsum, or ' outside,' and is separated from that home in which she was born, and transferred to another family.” 2 Moreover, Publius Nigidius, a man of prodigious learning, explains the word frater, or “brother,” by a no less clever and ingenious derivation: 3 “A frater,” he says, “is so called because he is, as it were, fere alter, that is, 'almost another self.'” 4