That a historian should not record trifles, that he should confine himself to what is important, is perfectly true. But many writers seem never to have considered on what the historical importance of an event depends. They seem not to be aware that the importance of a fact, when that fact is considered with reference to its immediate effects, and the importance of the same fact, when that fact is considered as part of the materials for the construction of a science, are two very different things. The quantity of good or evil which a transaction produces is by no means necessarily proportioned to the quantity of light which that transaction affords, as to the way in which good or evil may hereafter be produced. The poisoning of an emperor is in one sense a far more serious matter than the poisoning of a rat. But the poisoning of a rat may be an era in chemistry; and an emperor may be poisoned by such ordinary means, and with such ordinary symptoms, that no scientific journal would notice the occurrence. An action for a hundred thousand pounds is in one sense a more momentous affair than an action for fifty pounds. But it by no means follows that the learned gentlemen who report the proceedings of the courts of law ought to give a fuller account of an action for a hundred thousand pounds, than of an action for fifty pounds. For a cause in which a large sum is at stake may be important only to the particular plaintiff and the particular defendant. A cause, on the other hand, in which a small sum is at stake, may establish some great principle interesting to half the families in the kingdom. The case is exactly the same with that class of subjects of which historians treat. To an Athenian, in the time of the Peloponnesian war, the result of the battle of Delium was far more important than the fate of the comedy of The Knights. But to us the fact that the comedy of The Knights was brought on the Athenian stage with success is far more important than the fact that the Athenian phalanx gave way at Delium. Neither the one event nor the other has now any intrinsic importance. We are in no danger of being speared by the Thebans. We are not quizzed in The Knights. To us the importance of both events consists in the value of the general truth which is to be learned from them. What general truth do we learn from the accounts which have come down to us of the battle of Delium? Very little more than this, that when two armies fight, it is not improbable that one of them will be very soundly beaten, a truth which it would not, we apprehend, be difficult to establish, even if all memory of the battle of Delium were lost among men. But a man who becomes acquainted with the comedy of The Knights, and with the history of that comedy, at once feels his mind enlarged. Society is presented to him under a new aspect. He may have read and travelled much. He may have visited all the countries of Europe, and the civilised nations of the East.