When you solve a sum you go from "a" to "b" and from "b" to "c" and from "c" to "d" and so on. History on the other hand jumps from "a" to "z" and then back to "f" and next to "m" without any apparent respect for neatness and order. There is a good reason for this. History is not exactly a science. It tells the story of the human race and most people, however much we may try to change their nature, refuse to behave with the regularity and the precision of the tables of multiplication. No two men ever do precisely the same thing. No two human brains ever reach exactly the same conclusion. You will notice that for yourself when you grow up. It was not different a few hundred centuries ago. Prehistoric man, as I just told you, was on a fair way to progress. He had managed to survive the ice and the snow and the wild animals and that in itself, was a great deal. He had invented many useful things. Suddenly, however, other people in a different part of the world entered the race. They rushed forward at a terrible speed and within a very short space of time they reached a height of civilization which had never before been seen upon our planet. Then they set forth to teach what they knew to the others who had been less intelligent than themselves. Now that I have explained this to you, does it not seem just to give the Egyptians and the people of western Asia their full share of the chapters of this book? THE EARLIEST SCHOOL OF THE HUMAN RACE We are the children of a practical age. We travel from place to place in our own little locomotives which we call automobiles. When we wish to speak to a friend whose home is a thousand miles away, we say "Hello" into a rubber tube and ask for a certain telephone number in Chicago. At night when the room grows dark we push a button and there is light. If we happen to be cold we push another button and the electric stove spreads its pleasant glow through our study. On the other hand in summer when it is hot the same electric current will start a small artificial storm (an electric fan) which keeps us cool and comfortable. We seem to be the masters of all the forces of nature and we make them work for us as if they were our very obedient slaves. But do not forget one thing when you pride yourself upon our splendid achievements. We have constructed the edifice of our modern civilization upon the fundament of wisdom that had been built at great pains by the people of the ancient world. Do not be afraid of their strange names which you will meet upon every page of the coming chapters. Babylonians and Egyptians and Chaldeans and Sumerians are all dead and gone, but they continue to influence our own lives in everything we do, in the letters we write, in the language we use, in the complicated mathematical problems which we must solve before we can build a bridge or a skyscraper.