The Israeli farmers who pioneered the revolutionary technology known as drip irrigation weren't trying to solve one of the world's most urgent problems．They were just trying to survive．They lived in the desert，and they didn't have enough water to grow their crops．

    In its simplest form, it was little more than a pipe with holes in it. But behind each hole was a hi-tech dripper that let out just the right amount of water. Snaked along a row of crops so that the holes were positioned directly above the roots, the pipe could direct each precious drop of water directly to the plants, getting a bigger harvest while using a very small amount of the water．

    Over time, the farmers improved upon the technology, perfecting the drippers that regulated the flow of water, and connecting the pipelines to computers that could determine exactly how much water each plant needed and when．

    If the global population kept growing, the rest of the world would increasingly resemble their little community in the desert. So they began selling their irrigation systems in other parts of the world，eventually expanding to more than 110 countries. Netafirm, the company says it's lifting people out of poverty and conserving water at a time when the importance of doing so has never been clearer．

    The mass adoption of drip irrigation won't save the world by itself. To avoid the coming catastrophe, nearly everybody will, in some way, have to do more with less, perhaps through accepting and using other new technologies. Otherwise, it's going to get ugly．

    His Excellency

    Kim Jong Un

    Chairman of the State Affairs Commission of the Democratic People's Republic of Korea

Dear Mr. Chairman,

    We greatly appreciate your time, patience, and effort with respect to our recent negotiations and discussions relative to a summit (峰会) long sought by both parties, which was scheduled to take place on June 12 in Singapore.

    We were informed that the meeting was requested by North Korea, but that to us is totally irrelevant (不重要的). I was very much looking forward to being there with you.

    Sadly, based on the unacceptable and unfriendly statement, I feel it is not proper, at this time, to have this long-planned meeting.

    Therefore, please let this letter to serve to represent that the Singapore summit, for the good of both parties, but to the detriment of the world, will not take place.

    You talk about your nuclear capabilities (能力), but ours are so massive and powerful that I pray to God they will never have to be used.

    I felt a wonderful dialogue was building up between you and me, and ultimately, it is only that dialogue that matters. Some day, I look very much forward to meeting you.

    In the meantime, I want to thank you for the release of the hostages (人质) who are now home with their families. That was a beautiful gesture and was very much appreciated.

    If you change your mind having to do with this most important summit, please do not hesitate to call me or write. The world, and North Korea in particular, has lost a great opportunity for lasting peace and great prosperity and wealth. This missed opportunity is a truly sad moment in history.

Sincerely yours,

Donald J. Trump

    President of the United States of America

    Philosophy of Education is a label applied to the study of the purpose, process, nature and ideals of education. It can be considered a branch of both philosophy and education. Education can be defined as the teaching and learning of specific skills, and the imparting of knowledge, judgment and wisdom, and is something broader than the societal institution of education we often speak of.

    Many educationalists consider it a weak and imprecise field, too far removed from the practical applications of the real world to be useful. But philosophers dating back to Plato and the Ancient Greeks have given the area much thought and emphasis, and there is little doubt that their work has helped shape the practice of education over the millennia.

    Plato is the earliest important educational thinker, and education is an essential element in “The Republic” (his most important work on philosophy and political theory, written around 360 B.C.). In it, he advocates some rather extreme methods: removing children from their mothers' care and raising them as wards of the state, and differentiating children suitable to the various castes(社会等级), the highest receiving the most education, so that they could act as guardians of the city and care for the less able. He believed that education should be holistic(全面的), including facts, skills, physical discipline, music and art. Plato believed that talent and intelligence is not distributed genetically and thus is to be found in children born to all classes, although his proposed system of selective public education for an educated minority of the population does not really follow a democratic model.

    Aristotle considered human nature, habit and reason to be equally important forces to be cultivated in education, the ultimate aim of which should be to produce good and virtuous citizens. He proposed that teachers lead their students systematically, and that repetition be used as a key tool to develop good habits, unlike Socrates' emphasis on questioning his listeners to bring out their own ideas. He emphasized the balancing of the theoretical and practical aspects of subjects taught, among which he clearly mentions reading, writing, mathematics, music, physical education, literature, history, and a wide range of sciences, as well as play, which he also considered important.

    During the period of Middle Age, the idea of Perennialism was first formulated by St. Thomas Aquinas in his work “De Magistro”. Perennialism holds that one should teach those things deemed to be of everlasting importance to all people everywhere, namely principles and reasoning, not just facts (which are apt to change over time), and that one should teach first about people, not machines or techniques. It was originally religious in nature, and it was only much later that a theory of worldly Perennialism developed.

    During the Renaissance(文艺复兴), the French doubter Michel de Montaigne (1533 - 1592) was one of the first to critically look at education. Unusually for his time, Montaigne was willing to question the conventional wisdom of the period, calling into question the whole structure of the educational system, and the assumption that university-educated philosophers were necessarily wiser than uneducated farm workers, for example.

    Can you imagine being able to remember every single experience of your life and every word in your favorite book? That's what Becky's life is like, and as wonderful as it sounds, it can also be quite terrifying at times.

    Three years ago  Becky was reading a newspaper article which mentioned that it was impossible for people to remember the details of their life in the first three years. "What nonsense (胡说八道)!" she thought, because she could clearly remember her life all the way back to when she was just 12 days old. Her parents had carried her to the driver's seat of their car and laid her down for a photo. But it wasn't nonsense. She was just one of only 80 known people who have a condition called HSAM(Highly Superior Autobiographical Memory).

    Becky's unusual condition was recently shown on a program called 60 minutes, where reporter Allison tested her ability by asking her questions about her favorite book series, Harry Potter. Allison would pick up a book and open a page and read her a line. Immediately Becky would name the book, chapter number, chapter name and could recite every word until Allison told her to stop.

    Being able to remember every little detail is a great ability, but as every person with HSAM will tell you, it can be very hard to deal with. Forgetting is one of the things we use to get over sad experiences in our lives, but it's something that people like Becky are unable to do. Even walking on the street and lightly bumping(撞) into somebody brings back memories from Becky's childhood, when a boy knocked her over. She's taken right back to that time, living the experience all over again. Also, like Becky, people with HSAM never do well in school, because they have problems filtering(过滤) through all the information, remembering only the important bits.

    Becky's special brain could help scientists find a way to treat people with terrible illnesses like Alzheimer's. Her condition could hold the secret to treating or even preventing Alzheimer's.

    Scientists in Britain have managed to teach bees to pull strings (线) to get to food and then pass on what they have learned to others in their colony (群体) — showing a high level of intelligence despite their tiny brains.

    Researchers at Queen Mary University of London said the experiments, often used to test the intelligence of apes (猿) and birds, showed for the first time that some insects are up to the task, and can also pass skills on through several generations.

    The findings add to the evidence suggesting the ability for "culture spread"— the ability to learn and pass on knowledge and skills — may not be exclusive to humans.

    In the research, published in the journal PLOS Biology on Tuesday, the scientists were able to train 23 out of a group of 40 bees to pull strings with their legs and feet.

    The strings were attached to discs — or artificial "flowers"— containing food at their center but placed under a transparent (透明的) screen. The bees, spotting the food beneath the screen, learned to pull the "flowers" out by pulling the string with their legs and feet to be able to get to it.

    From another group of bees given the chance to solve the task without any training, only two of 110 were successful.

    Another group of bees was then allowed to observe the trained bees pulling the strings, and 60 percent of them successfully learned the skill. Finally, trained bees were put in colonies, and the scientists found the technique spread successfully to a majority of the colony's worker bees.

    Lars Chittka, a Queen Mary University professor who guided the project, said the team is interested in figuring out the brain processes behind the bees' learning and teaching skills.

Singapore researchers say they have developed a form of electronic skin that can create a sense of touch. They hope their invention will give people with prosthetic hands (假肢手) the ability to identify different objects.

The skin device measures 1 square centimeter. The system contains 100 small sensors that attempt to recreate things like texture (质地), temperature and even pain. The researchers call the device Asynchronous Coded Electronic Skin, or ACES, which can process information faster than humans' nervous system. Machine learning methods trained the device to recognize 20 to 30 different textures. It can even correctly read Braille letters most of the time, the researchers say.

The system does not require the users' movement to work. Humans need to slide to feel texture. But in this case the skin, with just a single touch, is able to detect textures of different roughness.

A demonstration showed that the device could identify the difference between a soft ball and a solid plastic one. "When you lose your sense of touch, you essentially become numb and prosthetic users face that problem, " said Benjamin Tee, leader of the research team. "So by recreating an artificial version of the skin, for their prosthetic devices, they can hold a hand and feel the warmth and feel that it is soft."

Tee said his idea for the device came from the movie Star Wars, when character Luke Skywalker loses his right hand and it is replaced with a robotic one. In the film, the new hand is able to experience touch sensations just like the real one.

The artificial skin technology is still going through experiments and development. But Tee said there had already been a lot of interest in the system, especially from the medical community. Tee said similar inventions that his team has developed include see-through skin that can repair itself when torn and a material for wearable electronic devices that gives off light.