For it was a disaster quite without parallel in the history of the land, and entirely unforeseen by any of its political-economy writers who, on the contrary, were always anticipating that danger would arise from an excess of population overrunning its means of subsistence, and becoming unmanageable through its size. Polybius, however, will have nothing to do with either priest or worker of miracles in this matter. He will not even seek that 'sacred Heart of Greece,' Delphi, Apollo's shrine, whose inspiration even Thucydides admitted and before whose wisdom Socrates bowed. How foolish, he says, were the man who on this matter would pray to God. We must search for the rational causes, and the causes are seen to be clear, and the method of prevention also. He then proceeds to notice how all this arose from the general reluctance to marriage and to bearing the expense of educating a large family which resulted from the carelessness and avarice of the men of his day, and he explains on entirely rational principles the whole of this apparently supernatural judgment.

Now, it is to be borne in mind that while his rejection of miracles as violation of inviolable laws is entirely A PRIORI - for discussion of such a matter is, of course, impossible for a rational thinker - yet his rejection of supernatural intervention rests entirely on the scientific grounds of the necessity of looking for natural causes. And he is quite logical in maintaining his position on these principles. For, where it is either difficult or impossible to assign any rational cause for phenomena, or to discover their laws, he acquiesces reluctantly in the alternative of admitting some extra-natural interference which his essentially scientific method of treating the matter has logically forced on him, approving, for instance, of prayers for rain, on the express ground that the laws of meteorology had not yet been ascertained. He would, of course, have been the first to welcome our modern discoveries in the matter. The passage in question is in every way one of the most interesting in his whole work, not, of course, as signifying any inclination on his part to acquiesce in the supernatural, but because it shows how essentially logical and rational his method of argument was, and how candid and fair his mind.

Having now examined Polybius's attitude towards the supernatural and the general ideas which guided his research, I will proceed to examine the method he pursued in his scientific investigation of the complex phenomena of life. For, as I have said before in the course of this essay, what is important in all great writers is not so much the results they arrive at as the methods they pursue. The increased knowledge of facts may alter any conclusion in history as in physical science, and the canons of speculative historical credibility must be acknowledged to appeal rather to that subjective attitude of mind which we call the historic sense than to any formulated objective rules. But a scientific method is a gain for all time, and the true if not the only progress of historical criticism consists in the improvement of the instruments of research.

Now first, as regards his conception of history, I have already pointed out that it was to him essentially a search for causes, a problem to be solved, not a picture to be painted, a scientific investigation into laws and tendencies, not a mere romantic account of startling incident and wondrous adventure. Thucydides, in the opening of his great work, had sounded the first note of the scientific conception of history.