This, then, is the second essential difference between the Hesperian and the Terrestrial conditions of life. The first being the fact of Non-reproduction, the second may be called the Law of Cyclical Organism. A third still remains for our investigation. This third essential difference was known, during the period of the ancient history of Hesperos, as the Law of Evanescence. But, before proceeding to explain it, I must premise that, since the commencement of the modern history, it has been ascertained that the real significance of this law was entirely misconceived in the earlier period. Though the facts, so far as they had been then observed, were sufficiently accounted for by it, the observations had been very far from complete. The reader has, of course, already noticed, as an obvious consequence of the fact of non-reproduction, that all the now existing rational inhabitants of Hesperos are contemporaneous with the sudden manifestation of rational life on her surface. Whatever appearances might seem to indicate, not one of them is under twenty thousand years of age. Even the lovely girl who made notes of my conversation was not a day under it, though, at that time, I should have found it very hard to believe the fact. I have already mentioned that there is no such thing as death from disease or other natural and necessary cause. Still other causes may exist, and to these a portion of the original population may have fallen victims, so that the present Hesperians may be only the survivors of the original creation. These, too, some day or other may in like manner disappear, and rational life may thus be ultimately obliterated from the face of the planet. Such indeed was for ages the prevailing belief. How the belief was found to be based on an erroneous view of the actual facts will appear when we come to the history of the wonderful discovery which marks the commencement of the modern history. But, as for the belief itself in the likelihood of extinction of life in the planet, its origin may be easily explained. Soon after the sudden creation, or manifestation, of the Hesperians, the people in contiguous districts began to fraternise with each other. By degrees small communities were formed; rude languages were invented; private property began to be acquired; the advantages of co-operation and division of labour were dimly discerned. But, side by side with these marks of progress, many discouraging symptoms appeared. These, perhaps the inseparable companions of advancing civilization, were simply envy, hatred, jealousy, and all kinds of malice, too often resulting in energetic quarrelling, blows, and wounds.