People can be addicted to different things, e.g. alcohol, drugs, certain foods, or even television. People who have such an addiction are compulsive, i.e they have a very powerful psychological need that they feel they must satisfy. According to psychologists, many people are compulsive spenders; they feel that they must spend money. This compulsion, like most others, is irrational-impossible to explain reasonably. For compulsive spenders who buy on credit, charge accounts are even more exciting than money. In other words, compulsive spenders feel that with credit, they can do anything. Their pleasure in spending enormous amounts is actually greater than the pleasures that they get from the things they buy.

    There is even a special psychology of bargain hunting. To save money, of course, most people look for sales, low prices, and discounts. Compulsive bargain hunters, however, often buy things that they don't need just because they are cheap. They want to believe that they are helping their budgets, but they are really playing an exciting game: when they can buy something for less than other people, they feel that they are winning. Most people, experts claim, have two reasons for their behavior: a good reason for the things that they do and the real reason.

    It is not only scientists, of course, who understand the psychology of spending habits, but also business people. Stores, companies and advertisers use psychology to increase business: they consider people's need for love, power, or influence, their basic values, their beliefs and opinions, and so on in their advertising and sales methods.

    Psychologists often use a method called “behavior therapy” to help individuals solve their personal problems. In the same was, they can help people who feel that they have problems with money.

    Reading can be a social activity. Think of the people who belong to book group. They choose books to read and then meet to discuss them. Now the website BookCrossing.com turns the page on the traditional idea of a book group.

    Members go on the site and register the books they own and would like to share. BookCrossing provides an identification number to stick inside the book. Then the person leaves it in a public place, hoping that the book will have an adventure, traveling far and wide with each new reader who finds it.

    Bruce Peterson, the managing director of BookCrossing, says, “The two things that change your life are the people you meet and books you read. BookCrossing combines both.”

    Members leave books on park benches and buses, in train stations and coffee shops. Whoever finds their book will go to the site and record where they found it.

    People who find a book can also leave a journal entry describing what they thought of it. E-mails are then sent to the BookCrossers to keep them updated about where their books have been found. Bruce Peterson says the idea is for people not to be selfish by keeping a book to gather dust on a shelf at home.

    BookCrossing is part of a trend among people who want to get back to the “real” and not the virtual(虚拟). The site now has more than one million members in more than one hundred thirty-five countries.

    The Asian country announced yesterday that China was putting tariffs or taxes on about $3 billion worth of imports from the U.S. The tariffs are on 128 American-made products, ranging from pork and fruit to steel pipes. This will make it more expensive for America businesses to sell those products in China. And China says this was done as a response to the tariffs that the U.S. recently put on imports of Chinese steel and aluminum.

    Meanwhile, U.S. President Donald Trump says more tariffs, new ones worth as much a $50 billion are being planned by the U.S. on additional goods from China. So, one big question is, will all this cause a trade war, when countries take turns putting tariffs on each other 's goods, causing prices to rise?

    We don't know yet. The U.S. and China ship hundreds of billions of dollars of goods back and forth every year. So, the tariffs we've seen so far are a tiny part of that. And America's treasury secretary says the U.S. and China are talking behind the scenes about how to prevent a possible trade war.

    But a number of experts are concerned this could turn into one and so are some stock investors. The Chinese tariffs were a major factor in a drop of the U.S. stock market yesterday when the Dow Jones Industrial Average fell 459 points. But just like it's hard to tell if a trade war is on the horizon, it's also hard to tell what kind of effects one could have decades down the road.

    Google's new camera, called Clips, is a small, smart device. It comes with a case that has a clip (夹子), but it's not designed to be worn on your clothing. Most interestingly, it uses artificial intelligence to take photography out of your hands so it can capture moments on its own.

    This roughly 2-inch by 2-inch camera, with a three-hour battery life and Gorilla Glass for toughness, is intended for candid moments, like when a child does something cute that may happen too quickly for you to pull out your smartphone.

    Onboard the Clips device, it uses machine learning algorithms ( 计 算 程 序 ) to help capture scenes. Those algorithms include face recognition. "Once it learns that there's a face you see frequently, it'll try to get nice photos of those faces," said Juston Payne, the device's product manager. And they also want it to recognize facial expressions, which involved "training it to know what happiness looks like". The Google team also trained it to recognize what not to shoot—like when a child's hand is over the lens, or if it is tossed in a dark purse.

    The only way to see the images is by connecting the camera with your phone, as it has no screen for viewing or editing.

    Were people concerned it could seem strange? Yes, Payne admitted. But they said they addressed that by making it obvious what it is. A green light on the front signals that it is on. Besides, unlike a camera meant to monitor your home, it is not connected to the Internet.

    "This product is only possible because of the way that silicon has advanced," Payne said, noting that it was only in the past year or so that they could squeeze the technology down into a device this size. Going forward, we're likely to get more assistance from the artificial intelligence packed into our apps and gadgets.

    Samuel Osmond is a 19-year-old law student from Cornwall, England. He never studied the piano. However, he can play very difficult musical pieces by musicians such as Chopin and Beethoven just a few minutes after he hears them. He learns a piece of music by listening to it in parts. Then he thinks about the notes(音符) in his head. Two years ago, he played his first piece Moonlight Sonata（奏鸣曲）by Beethoven. He surprised everyone around him.

    Amazed that he remembered this long and difficult piece of music and played it perfectly, his teachers say Samuel is unbelievable. They say his ability is very rare, but Samuel doesn't even realize that what he can do is special. Samuel wanted to become a lawyer as it was the wish of his parents, but music teachers told him he should study music instead. Now, he studies law and music.

Samuel can't understand why everyone is so surprised. "I grew up with music. My mother played the piano and my father played the guitar. About two years ago, I suddenly decided to start playing the piano, without being able to read music and without having any lessons. It comes easily to me —I hear the notes and can bear them in mind—each and every note," says Samuel.

Recently, Samuel performed a piece during a special event at his college. The piece had more than a thousand notes. The audience was impressed by his amazing performance. He is now learning a piece that is so difficult that many professional(专业的) pianists can't play it. Samuel says confidently, "It's all about super memory—I guess I have that gift."

    However, Samuel's ability to remember things doesn't stop with music. His family says that even when he was a young boy, Samuel heard someone read a story, and then he could retell the story word for word.

    Samuel is still only a teenager. He doesn't know what he wants to do in the future. For now, he is just happy to play beautiful music and continue his studies.

    A while back I caught a news report on something called -couch surfing‖ and the network of trusting souls who make this phenomenon possible. They offer to put up travelers free of charge and help them on their ways. At first, it sounded unbelievable. I mean, inviting strangers into one's home for one or two nights? Give me a break.

    However, I was intrigued. I decided to investigate. The only way to truly learn about this phenomenon was to dive in. So I planned a trip to Finland, a country I've always wanted to explore. I would couch surf at every stop there.

    If ever any anxiety existed when stepping into the unknown, it disappeared when my first host met me at the train station. Ari looked like my idea of a typical Finn: tall and blue-eyed. Finns were also supposed to be famously reserved (寡言少语的). Ari was anything but. He was a live wire, giving me an enthusiastic welcome and hiking with me to his apartment, where he showed me the sleeper sofa, served me tea, and engaged me in warm conversations. He also handed me a key to come and go as I pleased.

    If this was what couch surfing was all about－trust and friendship－then I had gotten off to a good start. As I boarded my next train to continue my journey, I began to think about this couch-surfing idea. What urged these people to open their homes to strangers? I concluded that there was a desire to lend a hand to like-minded folks who might enrich their own lives.

    Seven cities in 14 days. Seven hosts. Seven new friends. If couch surfing taught me anything, it's this: Most people are good and generous. Where will couch surfing take me next? Who knows? But I can't wait to find out.