These considerations, then, will enable us to understand first how it was that, radical and unscrupulous reformers as the Greek political theorists were, yet, their end once attained, no modern conservatives raised such outcry against the slightest innovation. Even acknowledged improvements in such things as the games of children or the modes of music were regarded by them with feelings of extreme apprehension as the herald of the drapeau rouge of reform. And secondly, it will show us how it was that Polybius found his ideal in the commonwealth of Rome, and Aristotle, like Mr. Bright, in the middle classes. Polybius, however, is not content merely with pointing out his ideal state, but enters at considerable length into the question of those general laws whose consideration forms the chief essential of the philosophy of history. He starts by accepting the general principle that all things are fated to decay (which I noticed in the case of Plato), and that 'as iron produces rust and as wood breeds the animals that destroy it, so every state has in it the seeds of its own corruption.' He is not, however, content to rest there, but proceeds to deal with the more immediate causes of revolutions, which he says are twofold in nature, either external or internal. Now, the former, depending as they do on the synchronous conjunction of other events outside the sphere of scientific estimation, are from their very character incalculable; but the latter, though assuming many forms, always result from the over-great preponderance of any single element to the detriment of the others, the rational law lying at the base of all varieties of political changes being that stability can result only from the statical equilibrium produced by the counteraction of opposing parts, since the more simple a constitution is the more it is insecure. Plato had pointed out before how the extreme liberty of a democracy always resulted in despotism, but Polybius analyses the law and shows the scientific principles on which it rests. The doctrine of the instability of pure constitutions forms an important era in the philosophy of history. Its special applicability to the politics of our own day has been illustrated in the rise of the great Napoleon, when the French state had lost those divisions of caste and prejudice, of landed aristocracy and moneyed interest, institutions in which the vulgar see only barriers to Liberty but which are indeed the only possible defences against the coming of that periodic Sirius of politics, the [Greek]