go over to the second point. To consider Japanese history as a miniature of the world's history is rather a new assertion, so that it requires conclusive justification. It is now generally believed or assumed that every nation continues to evolve as an individual does, till it reaches its climax of growth and begins to decay. Hence many modern historians have successively tried to extract certain principles by the process of induction from kindred historical events which took place in different countries and ages, and thus to raise the study of history to the rank of a science in the same sense as that in which the word is used when we speak of natural phenomena. It is a great pity, however, that every historical event is of a very ephemeral nature, never to be repeated in exactly the same form in which it once occurred. And if it passes away, it passes away forever, not to be retarded in the midst of its course by the will of an investigator. Often one can contribute with full consciousness to the happening of an event, or can alter the course of it, but one cannot undo by any means the event itself and wash the ground as if nothing had taken place. Moreover, historical facts are very difficult to detach from their environment entirely, however isolated they seem to be, and on that account they are not fit to be made objects of laboratory experiments. In a school classroom the pupils are taught to solve an algebraic equation of a binomial expression by supposing the value of x and y alternately to be equal to zero. How much the task of historians would be lightened, if we could for some time trace the effect of a certain cause exclusively, setting at naught other concurrent causes, as if those causes might be supposed to be standing still for a moment of observation or hypothetically cancelled for a necessary time! Strictly speaking, the above device is out of the question in the case of any historical investigation. Setting that aside, there is still another greater difficulty to encounter in the study of history. Every school-boy knows that there is a fundamental law in physics, that when a body is set in motion by a certain impetus, it will move on continuously in one direction with the same momentum, so long as it is left uninfluenced by any other new force. It is true, however, that such a case exists very rarely even in natural phenomena, and it would be quite absurd to look for the like in the domain of history. More than one cause acts conjointly upon individuals, families, tribes, or nations, and before those causes cease to influence, other new causes generally come into play, so that the influences of the latter are interwoven with those of the former causes or groups of causes, and make discrimination between them exceedingly difficult.