JUS NATURALE. The name given to those rules of conduct which are universally bind ing upon men and which are sanctioned by the dictates of right reason, as opposed to rules of conduct prescribed and enforced by the sovereign power of the state which are called positive law, known to the Romans as jus civile, and in modern jurisprudence as municipal law.
The jus naturaie, or law of nature, is sim ply the jus gentium, or law of nations, seen in the light of a peculiar theory. Maine, Anc. Law 52. Sir P. Pollock refers to this as "an unhappy term," which seems to be a mere external ornament borrowed from Greek philosophers • in excess of zeal to make a show of philosophical culture, and inconsist ent with the proper Roman use of jus. Ox ford Lectures 7.
A much quoted definition of Ulpian was that which nature attaches to animals. Of this it has been said that it was peculiar, and the conception exercised little or no influence upon the judicial thought of Rome. Morey, Rom. L. 111, where also are collected many definitions of the Roman jurists.
Sanders considers the passage from Ulpian unfor tunately borrowed by Justinian and thereby re moved from the connection in which it was used, which was a subsidiary and divergent line of thought, and had nothing to do with the main the ory. Accordingly "in considering what the Roman jurists meant by jus naturele this fragment of Ulpian may be dismissed almost entirely from our notice." Sand. Inst. Just. 7.
The conception of the jus naturale came from the Stoics and has been termed "by far the most im portant addition to the system of Roman law, which the jurists introduced from Greek philosophy."
Sand. Inst. Just. Introd. sail. And Maine says of it that "the importance of this theory to mankind has been very much greater than its philosophical de ficiencies would lead us to expect." Anc. L. 71. While it is undoubtedly true that the highest con ception of law is that natural law and positive law should be entirely harmonious, it Is in the domain of international law that this conception more nearly approaches realization. The jus pentium was a system largely based upon the jus naturals, and it is due to that fact that the Roman system ao largely formed the basis upon which Grotius commenced to build, the system which has develop ed into modern international law. It has been said that while be "rejected Ulpian's definition of the jus naturals, he accepted the idea of natural law expressed in the later jus gentium of the Romans as a body of principles based upon the common reason of mankind. It was therefore possible for him to extend the equitable principles already de veloped in the Roman jus pentium to the relations existing between sovereign states. States were looked upon as moral persons—subjecta of the nat ural law, and as equal to each other in their moral rights and obligations." Morey, Rom. L. 208. See JP° GENTIUM; LAW OF NATURE; LAW.