When Mark Twain trained as a steamboat pilot on the Mississippi River, the face of the water gradually became a book to him, one that told its secrets clearly to anyone who had learned its language. At first, he was proud of this new skill. But he soon realized that he had lost something, too. In his early days, a sunset on the river had filled him with wonder: the red glow spreading over the water, the floating logs, the soft lines of the distant forest. Later, the same scene carried only practical messages. The red sun warned that wind was coming the next day, and a slanting mark on the surface pointed to a dangerous reef. The grace, the beauty, and the poetry had gone out of the majestic river. He even wondered whether doctors suffer the same loss, seeing in the lovely blush on a person's cheek only a sign of hidden disease.

Many people assume that happiness simply happens to them, like good weather or bad luck. Yet our happiness depends far more on ourselves than on outside circumstances. Two people ①placed in exactly the same situation may feel completely different about it: one complains about every small trouble, while the other finds something to enjoy even on a rainy day. This difference is not ②what fortune decides; it comes largely from habits of mind. In fact, we have a duty to be as cheerful as we can, not only for our own sake but also for the sake of those around us, since a cheerful person ③making others happier simply by being present. A gloomy mood, on the other hand, spreads quickly through a family or a classroom. Of course, no one can avoid sorrow entirely. But we can choose ④to look for the bright side of things, and much of the unhappiness we suffer ⑤is caused by our own carelessness rather than by fate.

Teachers often complain that students cannot keep their minds on a lesson for long. But this is not simply a weakness of young people; it is a law of the mind. No one can attend continuously to an object that does not change. Try to stare at a single dot on a wall, and within a few seconds your attention will drift away, or the dot itself will seem to fade. To keep the mind on one thing, we must keep finding new questions to ask about it, turning it over and looking at it from fresh angles. The same holds true in the classroom. A teacher who repeats the same point in the same way will soon lose the class, however important the point may be. The secret of holding attention, then, is not to demand it more loudly, but to make sure that the subject .

When Benjamin Franklin was a teenager, he came across an old volume of The Spectator, a famous English magazine. He thought the writing was excellent and wished to imitate it. ( ① ) So he took a few of the essays and wrote short notes on the meaning of each sentence. ( ② ) He then put the notes aside for several days. ( ③ ) Afterward, without looking at the book, he tried to rewrite the essays in his own words, using only his notes. ( ④ ) By noticing the differences, he discovered many of his faults and corrected them. ( ⑤ ) Sometimes he even turned the stories into poems and later turned them back into prose, which forced him to search for a wider variety of words. Through this patient practice, the boy who had left school at the age of ten became one of the finest writers in America.

A carpenter carries a piece of chalk in his pocket without giving it a second thought. To him, it is merely a tool for marking wood. Yet that small white lump holds a remarkable story. Under a microscope, chalk turns out to be made largely of the tiny shells of microscopic sea creatures. When these creatures died, their shells sank and piled up on the ocean floor, layer upon layer, over countless years. Chalk, in other words, is the dried mud of an ancient deep sea, which means that the white cliffs of southern England were once covered by water. A great chapter in the history of the world is thus written in the chalk. Its language is not hard to learn; all we need is the curiosity to ask where an everyday object came from and the patience to read the evidence it carries.