There was a marked difference between the development of law and that of the other subjects so far treated by Isidore in the _Etymologies_. The latter were of Greek origin, and, with the exception of rhetoric, they appeared as strangers in the Roman environment and never formed an integral part of Roman culture. Instead, they suffered from continuous decay, and by the time of the disintegration of the Roman state they were reduced to such a condition that the “fall of Rome” meant nothing to them. On the other hand, law was an indigenous product of Roman society, upon which the Roman intellect had expended its greatest and most successful efforts, and although it inevitably shared in the general intellectual deterioration of the time, and showed a marked decline after the period of the great jurists, the beginning of its rapid decay is coincident in each section of western Europe with the close of Roman rule. Thus “the fall of Rome” played much the same part in the history of law as the transition from a Greek to a Roman environment had done for the bulk of the intellectual possession of the ancient civilization. After this event law was on terms of equality with the other branches of knowledge, and within two centuries, as judged by its presentation in the _Etymologies_, it was reduced to as low an estate as they. Isidore’s _De Legibus_ is divided into two distinct parts. The first is of a general nature, and embraces such topics as law-givers, _jus civile_, _jus gentium_, _jus naturale_, why laws are made, and what character a law ought to have. The second part is more specific; it treats of legal instruments, the law of property, crimes, and punishments. The whole forms a scholastic conglomerate of elements derived from every stage in the development of Roman law and exhibits a point of view that is philological and Christian as much as legal. Because of its importance in the history of law, this book of the _Etymologies_ has been subjected to more detailed study than any other, but in spite of this its sources have not been clearly determined. In addition to the Scriptures and Isidore’s authorities on word derivation, he is believed to have drawn on the _Breviarium Alaricianum_, the Theodosian code, the text-books of Gaius and Ulpian, and the _Sentences_ of Paulus. Although the Justinian code was issued a century before the compilation of the _Etymologies_, it seems improbable that Isidore made any use of it, or had even heard of it.[292]