But in figure II (which is no longer a perfect circle) trade has got an undue advantage at the expense of politics and art has almost entirely disappeared, while militarism shows a gain. Or make GH (militarism) the longest diameter, and the others will tend to disappear altogether. [Illustration: III] You will find this a handy key to a great many historical problems. Try it on the Greeks. For a short time the Greeks had been able to maintain a perfect circle of all-around accomplishments. But the foolish quarrels between the different political parties soon grew to such proportions that all the surplus energy of the nation was being absorbed by the incessant civil wars. The soldiers were no longer used for the purpose of defending the country against foreign aggression. They were turned loose upon their own neighbors, who had voted for a different candidate, or who believed in a slightly modified form of taxation. Trade, that most important diameter of all such circles, at first became difficult, then became entirely impossible and fled to other parts of the world, where business enjoyed a greater degree of stability. The moment poverty entered through the front gate of the city, the arts escaped by way of the back door, never to be seen again. Capital sailed away on the fastest ship it could find within a hundred miles, and since intellectualism is a very expensive luxury, it was henceforth impossible to maintain good schools. The best teachers hastened to Rome and to Alexandria. What remained was a group of second-rate citizens who subsisted upon tradition and routine. And all this happened because the line of politics had grown out of all proportion, because the perfect circle had been destroyed, and the other lines, art, science, philosophy, etc., etc., had been reduced to nothing. If you apply the circular problem to Rome, you will find that there the particular line called “political power” grew and grew and grew until there was nothing left of any of the others. The circle which had spelled the glory of the Republic disappeared. All that remained was a straight, narrow line, the shortest distance between success and failure. And if, to give you still another example, you reduce the history of the medieval Church to this sort of mathematics, this is what you will find. The earliest Christians had tried very hard to maintain a circle of conduct that should be perfect. Perhaps they had rather neglected the diameter of science, but since they were not interested in the life of the world, they could not very well be expected to pay much attention to medicine or physics or astronomy, useful subjects, no doubt, but of small appeal to men and women who were making ready for the last judgment and who regarded this world merely as the ante-room to Heaven.