But what is the twenty-fifth century in comparison with the thirtieth, the fortieth, the hundredth!
Everyone knows the legend of the Arab of Kazwani, as related by a traveller of the thirteenth century, who at that time, moreover, had no idea of the duration of the epochs of nature. “Passing one day,” he said, “by a very ancient and very populous city, I asked one of its inhabitants how long a time it had been founded. ‘Truly,’ he replied, ‘it is a powerful city, but we do not know how long it has existed, and our ancestors are as ignorant upon this subject as we.’
“Five centuries later I passed by the same spot, and could perceive no trace of the city. I asked a peasant who was gathering herbs on its former site, how long it had been destroyed. ‘Of a truth,’ he replied, ‘that is a strange question. This field has always been what it now is.’ ‘But was there not formerly a splendid city here?’ I asked. ‘Never,’ he answered, ‘at least so far as we can judge from what we have seen, and our fathers have never told us of any such thing.’
“On my return five hundred years later to the same place I found it occupied by the sea; on the shore stood a group of fishermen, of whom I asked at what period the land had been covered by the ocean. ‘Is that question worthy of a man like you?’ they replied; ‘this spot has always been such as you see it today.’
“At the end of five hundred years I returned again, and the sea had disappeared. I inquired of a solitary man whom I encountered, when this change had taken place; and he gave me the same reply.
“Finally, after an equal lapse of time, I returned once more, to find a flourishing city, more populous and richer in monuments than that which I had at first visited; and when I sought information as to its origin, its inhabitants replied: ‘The date of its foundation is lost in antiquity. We do not know how long it has existed, and our fathers knew no more of this than we do.’”
How this fable illustrates the brevity of human memory and the narrowness of our horizons in time as well as in space! We think that the earth has always been what it now is; we conceive with difficulty of the secular changes through which it has passed; the vastness of these periods overwhelms us, as in astronomy we are overwhelmed by the vast distances of space.