Except where the context shows that it is not so, we shall use the term in the first of these senses.
[107]. A composite state may be of a mixed nature, being partly imperial and partly federal. A federal state may have dependencies, over which it exercises an imperial government—the foreign conquests, for example, of the United States of America. So an imperial state may have dependencies, which are themselves federal states. The Commonwealth of Australia is a federal union which is a dependency under imperial government.
[108]. D. 50. 17. 207.
[109]. In addition to the formal, historical, and legal sources of the law, it is necessary to note and distinguish what may be termed its literary sources, though this is a Continental, rather than an English use of the term source. The literary sources are the sources of our knowledge of the law, or rather the original and authoritative sources of such knowledge, as opposed to later commentary or literature. The sources of Roman law are in this sense the compilations of the Emperor Justinian, as contrasted with the works of commentators. So the sources of English law are the statute-book, the reports, and the older and authoritative text-books, such as Littleton. The literature, as opposed to the sources of our law, comprises all modern text-books and commentaries.
[110]. In the succeeding chapters we shall consider more particularly three of the legal sources which have been already mentioned, namely legislation, custom, and precedent. Professional opinion as a source of law pertains to the Roman, rather than to the English system, and does not call for special examination here. For an account of it see Bryce, Studies in History and Jurisprudence, II. pp. 255–269. Agreement will be considered later, in its aspect as a title of rights, instead of here as a source of law.
[111]. Austin, p. 538.
[112]. Austin, p. 531.
[113]. Constat autem jus nostrum aut ex scripto aut ex non scripto.... Ex non scripto jus venit, quod usus comprobavit. Just. Inst. 1. 2. 3.; 1. 2. 9.
“The municipal law of England may with sufficient propriety be divided into two kinds: the lex non scripta, the unwritten or common law; and the lex scripta, the written or statute law.” Blackstone, I. 63.
[114]. Blackstone, I. 161.