nally characterized, affords a distinct congeries of logical subdivisions which is invariably reproduced over and over again.
It is, then, in this identity of structure of human society in every state, that law discovers for itself the basis of its constantly-recurrent methods of classification and its unchangeable conceptions. There are, however, certain other more obvious grounds for the permanence and invariability of legal ideas and methods which follow from the identity of man's physical, logical, and ethical structure in all times and in all parts of the world, within the limits to which observation has hitherto extended.
Law in its outward character consists of a body of commands addressed to individual members of the human race forming the component elements of a state. The issuing of commands involves the possibility of obedience or of disobedience, and therein supposes the presence of will, of liberty of action, and of the amount of intelligence needed to understand the purport of the commands. Attention is thereby compelled to the exceptional cases in which the terms of the command cannot be understood, whether through temporary incapacity, as infancy, error, or passing disease; or through permanent incapacity, as life-long insanity; or in which the terms cannot be complied with, through the pressure of external force, the interference of persons actuated by fraudulent motives, or the obstruction of physical facts creating the condition of impossibility.
Supposing, however, that the command can be understood and can be obeyed, there will be nevertheless cases presented in which the question has to be decided whether, as a matter of fact, the command, in a given case, was obeyed or not. Here are let in all the obstacles inherent in human nature itself to acquiring a correct knowledge of facts. All the current imperfections of human observation, all the insufficiency of language and expression, all the chicanery and double-mindedness, all the dullness of intellect, by which it becomes so hard to pass truth on unimpaired from hand to hand, are present to hamper the effort to apply and execute a single law. The several forms of these obstacles, however, are not peculiar to any one state nor to any one period, however their magnitude may vary. They are universally present, and can be classified under a comprehensive scheme.
But another and universal class of difficulties in executing a law has yet to be mentioned. It may be uncertain what are the form and intent of the law itself. If the law is written, the terms of the language in which it is written may admit of all sorts of ambiguity or vacillation in meaning, or, however certain the terms themselves, the opposed disputants may insist on different senses being put upon the whole text of the command.
If the law is unwritten, and has to be gathered either from traditional report or by reference to the rules which have been laid down on previous occasions in cases resembling the one now calling for de-
