“Nobody.” He shook his head. Then, rather anxiously, as though he were afraid there might be something wrong about drawing squares, he went on to apologise and explain. “You see,” he said, “it seemed to me so beautiful. Because those squares”--he pointed at the two small squares in the first figure--“are just as big as this one.” And, indicating the square on the hypotenuse in the second diagram, he looked up at me with a deprecating smile. I nodded. “Yes, it’s very beautiful,” I said--“it’s very beautiful indeed.” An expression of delighted relief appeared on his face; he laughed with pleasure. “You see, it’s like this,” he went on, eager to initiate me into the glorious secret he had discovered. “You cut these two long squares”--he meant the rectangles--“into two slices. And then there are four slices, all just the same, because, because--oh, I ought to have said that before--because these long squares are the same, because those lines, you see....” “But I want a train,” protested Robin. Leaning on the rail of the balcony, I watched the children below. I thought of the extraordinary thing I had just seen and of what it meant. I thought of the vast differences between human beings. We classify men by the colour of their eyes and hair, the shape of their skulls. Would it not be more sensible to divide them up into intellectual species? There would be even wider gulfs between the extreme mental types than between a Bushman and a Scandinavian. This child, I thought, when he grows up, will be to me, intellectually, what a man is to a dog. And there are other men and women who are, perhaps, almost as dogs to me. Perhaps the men of genius are the only true men. In all the history of the race there have been only a few thousand real men. And the rest of us--what are we? Teachable animals. Without the help of the real men, we should have found out almost nothing at all. Almost all the ideas with which we are familiar could never have occurred to minds like ours. Plant the seeds there and they will grow; but our minds could never spontaneously have generated them. There have been whole nations of dogs, I thought; whole epochs in which no Man was born. From the dull Egyptians the Greeks took crude experience and rules of thumb and made sciences. More than a thousand years passed before Archimedes had a comparable successor. There has been only one Buddha, one Jesus, only one Bach that we know of, one Michelangelo.