What has been said will explain the failure of all theories which consider the law only from its formal side; whether they attempt to deduce the corpus from a priori postulates, or fall into the humbler error of supposing the science of the law to reside in the elegantia juris, or logical cohesion of part with part.  The truth is, that the law always approaching, and never reaching, consistency.  It is forever adopting new principles from life at one end, and it always retains old ones from history at the other, which have not yet been absorbed or sloughed off.  It will become entirely consistent only when it ceases to grow.

The study upon which we have been engaged is necessary both for the knowledge and for the revision of the law. [37] However much we may codify the law into a series of seemingly self-sufficient propositions, those propositions will be but a phase in a continuous growth.  To understand their scope fully, to know how they will be dealt with by judges trained in the past which the law embodies, we must ourselves know something of that past.  The history of what the law has been is necessary to the knowledge of what the law is.

Again, the process which I have described has involved the attempt to follow precedents, as well as to give a good reason for them.  When we find that in large and important branches of the law the various grounds of policy on which the various rules have been justified are later inventions to account for what are in fact survivals from more primitive times, we have a right to reconsider the popular reasons, and, taking a broader view of the field, to decide anew whether those reasons are satisfactory.  They may be, notwithstanding the manner of their appearance.  If truth were not often suggested by error, if old implements could not be adjusted to new uses, human progress would be slow.  But scrutiny and revision are justified.

But none of the foregoing considerations, nor the purpose of showing the materials for anthropology contained in the history of the law, are the immediate object here.  My aim and purpose have been to show that the various forms of liability known to modern law spring from the common ground of revenge.  In the sphere of contract the fact will hardly be material outside the cases which have been stated in this Lecture.  But in the criminal law and the law of torts it is of the first importance.  It shows that they have started from a moral basis, from the thought that some one was to blame.

[38] It remains to be proved that, while the terminology of morals is still retained, and while the law does still and always, in a certain sense, measure legal liability by moral standards, it nevertheless, by the very necessity of its nature, is continually transmuting those moral standards into external or objective ones, from which the actual guilt of the party concerned is wholly eliminated.

LECTURE II.

THE CRIMINAL LAW.