Rules of law are in fact the institution of conditions under which persons make their arrangements with one another. They are structures which canalize action; they are active forces only as are banks which confine the flow of a stream, and are commands only in the sense in which the banks command the current. If individuals had no stated conditions under which they come to agreement with one another, any agreement would either terminate in a twilight zone of vagueness or would have to cover such an enormous amount of detail as to be unwieldy and unworkable. Each agreement, moreover, might vary so from every other that nothing could be inferred from one arrangement as to the probable consequences of any other. Legal rules state certain conditions which when met make an agreement a contract. The terms of the agreement are thereby canalized within manageable limits, and it is possible to generalize and predict from one to another. Only the exigencies of a theory lead one to hold that there is a command that an agreement be made in such and such a form.2 What happens is that certain conditions are set such that if a person conform to them, he can count on certain consequences, while if he fails to do so he cannot forecast consequences. He takes a chance and runs the risk of having the whole transaction invalidated to his loss. There is no reason to interpret even the “prohibitions” of criminal law in any other way. Conditions are stated in reference to consequences which may be incurred if they are infringed or transgressed. We can similarly state the undesirable results which will happen if a stream breaks through its banks; if the stream were capable of foreseeing these consequences and directing its behavior by the foresight, we might metaphorically construe the banks as issuing a prohibition.
This account explains both the large arbitrary and contingent element in laws and their plausible identification with reason, dissimilar as are the two considerations. There are many transactions in which the thing of chief importance is that consequences be determinate in some fashion rather than that they be determined by some inherent principle to be just such and such. In other words, within limits it is indifferent what results are fixed by the conditions settled upon; what is important is that the consequences be certain enough to be predictable. The rule of the road is typical of a large number of rules. So is the fixing of sunset or of a specified hour as the exact time when the felonious entering of the premises of another takes on a more serious quality. On the other hand, rules of law are reasonable so that “reason” is appealed to by some as their fount and origin on the ground pointed out by Hume.3 Men are naturally shortsighted, and the shortsightedness is increased and perverted by the influence of appetite and passion. “The law” formulates remote and long-run consequences. It then operates as a condensed available check on the naturally overweening influence of immediate desire and interest over decision. It is a means of doing for a person what otherwise only his own foresight, if thoroughly reasonable, could do. For a rule of law, although it may be laid down because of a special act as its occasion, is formulated in view of an indefinite variety of other possible acts. It is necessarily a generalization; for it is generic as to the predictable consequences of a class of facts. If the incidents of a particular occasion exercise undue influence upon the content of a rule of law, it will soon be overruled, either explicitly or by neglect. Upon this theory, the law as “embodied reason” means a formulated generalization of means and procedures in behavior which are adapted to secure what is wanted. Reason expresses a function, not a causal origin. Law is reasonable as a man is sensible who selects and arranges conditions adapted to produce the ends he regards as desirable. A recent writer, who regards “reason” as that which generates laws, says, “A debt does not in reason cease to be a debt because time has passed, but the law sets up a limitation. A trespass does not cease in reason to be a trespass because it is indefinitely repeated, yet the law shows a tendency to admit an unresisted trespass in time to the status of right. Time, distance and chance are indifferent to pure reason; but they play their part in the legal order.”4 But if reasonableness is a matter of adaptation of means to consequences, time and distance are things to be given great weight; for they effect both consequences and the ability to foresee them and to act upon them. Indeed, we might select statutes of limitation as excellent examples of the kind of rationality the law contains. Only if reason is looked upon as “pure,” that is as a matter of formal logic, do the instances cited manifest limitation of reason.
A third mark of
