It was a village in India. The people were poor. However, they were not unhappy. After all, their forefathers had lived in the same way for centuries.

    Then one day, some visitors from the city arrived. They told the villagers there were some people elsewhere who liked to eat frog's legs. However, they did not have enough frogs of their own, and so they wanted to buy frogs from other place.

    This seemed like money for nothing. There were millions of frogs in the fields around, and they were no use to the villagers. All they had to do was catch them. Agreement was reached, and the children were sent into the fields to catch frogs. Every week a truck arrived to collect the catch and hand over the money. For the first time, the people were able to dream of a better future.

    But the dream didn't last long. The change was hardly noticed at first, but it seemed as if the crops were not doing so well. More worrying was that the children fell ill more often, and, there seemed to be more insects around lately.

    The villagers decided that they couldn't just wait to see the crops failing and the children getting weak. They would have to use the money earned to buy pesticides(杀虫剂) and medicines. Soon there was no money left.

    Then the people realized what was happening. It was the frog. They hadn't been useless. They had been doing an important job—eating insects. Now with so many frogs killed, the insects were increasing more rapidly. They were damaging the crops and spreading diseases.

    Now, the people are still poor. But in the evenings they sit in the village square and listen to sounds of insects and frogs. These sounds of the night now have a much deeper meaning.

    The human brain contains 10 thousand million cells and each of these may have a thousand connections. Such enormous numbers used to discourage us and cause us to dismiss the possibility of making a machine with human-like ability, but now that we have grown used to moving forward at such a pace we can be less sure. Quite soon, in only 10 or 20 years perhaps, we will be able to assemble a machine as complex as the human brain, and if we can we will. It may then take us a long time to render it intelligent by loading in the right software (软件)or by altering the architecture but that too will happen.

    I think it certain that in decades, not centuries, machines of silicon (硅) will arise first to compete and then do better than their human ancestors. Once they do better than us they will be capable of their own design. In a real sense they will be able to reproduce themselves. Silicon will have ended carbon's long control. And we will no longer be able to claim ourselves to be the finest intelligence in the known universe.

    As the intelligence of robots increases to match that of humans and as their cost declines through economies of scale we may use them to improve environments. Thus, deserts may bloom and the ocean beds be mined. Further ahead, by a combination of the great wealth this new age will bring and the technology it will provide, the construction of a vast, man-created world in space, home to thousands or millions of people, will be within our power.

    Kung fu is one of a number of Chinese martial arts designed to improve the body and the mind. It is perhaps one of the most widely known martial arts, because many films include its techniques. There are hundreds of styles taught all over the world, although they can be loosely divided into two camps: Shaolin style kung fu, and other techniques, some of which have a history that outdates the Shaolin order.

    Shaolin kung fix has its origins in the fifth century. Like some other martial arts, it began in religious temples, where the monks sought a mind and body discipline (训练方法). In addition to the fighting style, it also includes mental exercises and religious practices designed to balance the whole body.

    Shaolin temples resembled universities, integrating a wide range of subjects of study. Therefore, traditional Shaolin styles such as Wing Chun, Crane, Praying Mantis, and Hung Gar took knowledge from fields outside martial arts, such as the healing arts and meditation. Supporters for Shaolin styles believe that they are more rounded martial arts styles, and that learners will benefit from them on a whole body level.

    Other fighting styles, some of which predate the Shaolin style, are also lumped under the kung fu umbrella. They include Pa-Kua, Eagle Claw, and Eight Drunken Immortals styles. These disciplines are not considered to be Shaolin style because they did not originate in temples and are focused primarily on fighting techniques.

    Whether Shaolin or otherwise, kung fu is characterized by self defense strategies that turn the energy of an attacker against him or her. Although the techniques may vary, most styles teach throws, kicks, punches, and the use of weapons. In addition to the physical discipline, most place a great importance on respect, honor, and living a balanced life.

    The values of artistic works, according to cultural relativism（相对主义）, are simply reflections of local social and economic conditions. Such a view, however, fails to explain the ability of some works of art to excite the human mind across cultures and through centuries.

    History has witnessed the endless productions of Shakespearean plays in every major language of the world. It is never rare to find that Mozart packs Japanese concert halls, as Japanese painter Hiroshige does Paris galleries. Unique works of this kinds are different from today's popular art, even if they began as works of popular art. They have set themselves apart in their timeless appeal and will probably be enjoyed for centuries into the future.

    In a 1757 essay, the philosopher David Hume argued that because “the general principles of taste are uniform（不变的）in human nature,” the value of some works of art might be essentially permanent. He observed that Homer was still admired after two thousand years. Works of this type, he believed, spoke to deep and unvarying features of human nature and could continue to exist over centuries.

    Now researchers are applying scientific methods to the study of the universality of art. For example, evolutionary psychology is being used by literary scholars to explain the long-lasting themes and plot devices in fiction. The structures of musical pieces are now open to experimental analysis as never before. Research findings seem to indicate that the creation by a great artist is as permanent an achievement as the discovery by a great scientist.

    Nola (August 21, 1974 -November 22, 2015) was a northern white rhino who lived at the San Diego Zoo Safari Park near Escondido, California. At her death, she was one of only four remaining northern white rhinos in the world. The other three lived in Kenya. World Rhino Day, held on September 2, is to raise awareness(意识) of the less than 30,000 other rhinos left on Earth.

    “Rhinos need our help today, not tomorrow,” Nola's lead keeper Jane Kennedy said. “Last year we lost over 1,200 rhinos just in South Africa. If we continue to lose more than 1,000 rhinos a year, in 10 to 20 years all the rhinos on the planet will be gone.”

    “Unfortunately, most animals are in danger of dying out because of humans,” Kennedy says.“ Humans have either poached animals, or because there are over seven billion of us, we've taken up too much of the world's resources”. Poachers illegally hunt rhinos for their horns. They sell the horns for thousands of dollars per pound, to be used for art, jewelry, and decorations. Experts believe that one rhino is poached every eight hours.

    In 1975, the San Diego Zoo Institute for Conservation Research started the Frozen Zoo, a program through which researchers have collected cell (细胞) samples from more than 8,000 different types of animals, including the northern white rhino. Scientists hope that by studying the rhino cells, they will get greater understanding of it, and will find ways to increase its numbers.

    Jane Kennedy describes World Rhino Day as “a celebration of rhinos along with an awareness campaign for everybody across the world to know that rhinos need our help.”At the San Diego Zoo, children and adults are welcome to visit and speak with zookeepers to learn about rhinos. But you don't have to live in San Diego to celebrate World Rhino Day. It is observed around the world, with zoos and wildlife parks holding special events and programs to teach people about rhinos, and enable them to see the animals up close. For more information, go to www.worldrhinoday.org.

    Crossing your legs is an extremely common habit. While you may find it comfortable to sit with one knee crossed over the other, it might be causing health problems that you are not aware of.

    A study published in Blood Pressure Monitoring stated that sitting with your legs crossed can increase your blood pressure. The reason is that crossing one leg over the other increases resistance, making it even harder for the blood to circulate and increase your blood pressure. Thus, you shouldn't have your legs crossed for more than 15 minutes, and it's important that you get up and walk around at least once every hour.

    Crossing your legs can also lead to neck and back pain. Ideally, it's best for our bodies to sit with our feet planted flat on the floor. When you sit with your legs crossed your hips are in a twisted position, which can cause pressure on your lower and middle back and neck.

    You also might notice that when you sit with your legs crossed for long periods of time your feet and legs get painful. This is because when one leg sits on top of the other, it causes pressure on the veins and nerves in your legs and feet. While the feeling of discomfort may only last a minute or two, repeatedly crossing your legs until they feel numb can cause permanent nerve damage.

    So next time you sit down, try to get yourself in the habit of sitting with both of your feet on the floor. Not only will it help your posture and stability, but it will also save your health in the long run.