That robots, automation, and software can replace people might seem obvious to anyone who's worked in automotive manufacturing. But MIT business scholars Erik Brynjolfsson and Andrew McAfee's claim is more troubling and controversial. They believe that rapid technological change has been destroying jobs faster than it is creating them.

    They believe that technology increases productivity and makes societies wealthier, but it became clear to them that the same technologies making many jobs safer, easier, and more productive were also reducing the demand for many types of human workers. Technologies like the Web, artificial intelligence, and big data are automating many routine tasks. Countless traditional white-collar jobs, such as many in the post office and in customer service, have disappeared.

    As evidence, Brynjolfsson and McAfee point to a chart on which separate lines represent productivity and total employment in the United States. For years after World War II, the two lines closely tracked each other, with increases in jobs corresponding to increases in productivity. Then, beginning in 2000, the lines diverge; productivity continues to rise steadily, but employment suddenly shrinks. By 2011, a significant gap appears between the two lines, showing economic growth with no parallel increase in job creation.

United States Productivity and Employment

    But are these new technologies really responsible for a decade of lackluster (无生气) job growth? David Autor, an economist at MIT who has studied the connections between jobs and technology, doubts that technology could account for such a sudden change in total employment. Moreover, he also doubts that productivity has, in fact, risen steadily in the United States in the past decade. If he's right, it raises the possibility that poor job growth could be simply a result of a depressed economy. The sudden slowdown in job creation “is a big puzzle,” he says, “but there's not a lot of evidence that it's linked to computers.” “To be sure, computer technologies are changing the types of jobs available, but that is very different from saying technology is affecting the total number of jobs,” he adds. “Jobs can change a lot without there being huge changes in employment rates.”

    Lawrence Katz, a Harvard economist, says that while technological changes can be painful for workers whose skills no longer match the needs of employers, no historical pattern shows these shifts leading to a net decrease in jobs over an extended period. Still, Katz doesn't dismiss the notion that there is something different about today's digital technologies. Though he expects the historical pattern to hold, it is “genuinely a question,” he says. “If technology disrupts enough, who knows what will happen?”

    This may be music to your ears.

    Researchers P Jason Rentfrow and Samuel Gosling gave 3, 500 people a personality quiz. Then they asked them to name their favourite kind of music. "We found that the musical styles people like are closely linked to their personalities," Gosling says.

    RAP/HIP－HOP

    Known for their quick speech, some rappers can say more than 700 syllables (音节)a minute! If you like rap/hip－hop, you are energetic(精力充沛的)and have a way with words. You put a fresh spin on things, whether it's new moves on the dance floor or your hip style.

    CLASSICAL

    In the 18th century, classical musicians were like rock stars. Beethoven and Mozart, for example, played to packed concert halls.  If you like classical, you are open to new ideas and like debating with friends. Creative and imaginative, you can easily spend many hours scrapbooking, writing or painting.

    COUNTRY

    Country music came from the folk songs of English, Scottish, and Irish settlers of the southeastern United States. If you like country, you express your opinions well, which makes you the ideal class president or team captain. Traditional and loyal, you enjoy spending time with your family.

    POP

    Pop music is designed to appeal to(吸引)almost everyone, and it does. Each year, the industry brings in about 30 billion dollars! If you like pop, you are attractive to your friends. You can make big things happen, like planning for a huge party or inspiring your team to victory.

    ROCK/ALTERNATIVE

    In the 1950s, rock music created a brand－new culture. Teenagers, for the first time, had an identity(身份)separate from adults and children.

    If you like rock/alternative, you are a risk－taker who never accepts no for an answer. You rise to any challenge, like doing very well in a big exam or in the school play.

    If these personality profiles don't match you, that's OK. These are just for fun.

    The annual World Economic Forum took place in Davos, Switzerland, in Jan. 23-26, 2018. What did Chinese entrepreneurs （企业家）speak in the forum? Are there some quotable quotes for you?

    Jack Ma, founder and executive chairman of Alibaba Group

    "I think globalization cannot be stopped — no one can stop globalization, no one can stop trade. If trade stops, the world stops. Trade is the way to dissolve (结束) the war not cause the war," said Ma in Davos, "Google, Facebook, Amazon and Alibaba — we are the luckiest companies of this century. But we have the responsibility to have a good heart, and do something good."

    Richard Liu, founder and chief executive officer of JD

    "Business is not only a way to make money but also a way to contribute yourself, to help people," Liu said in a speech in Davos. "How can we face the fractured (分化的) world? That's the topics of the Davos this year. I think a very important thing in business is cooperation. If we can unite, work together, if we work very closely, I think we can bring more hope to the people and we can build more trust between the people, countries and companies and partners," he said.

    Jane Sun, CEO of Ctrip

    "Tourism is a sunrise industry. Since I entered Ctrip, every year there are new comers, which, first of all, shows that tourism is booming." Sun told Sina.com in Davos. "We invested heavily in ABC. A refers to AI, B is big data, and C is cloud computing. As we continue to expand overseas, these three will be very good weapons for us. So we think those mean opportunity," she said.

    Hu Xiaoming, president of Aliyun

    "In 2018, people will see the development in various countries more closely connected with cloud computing. More manufacturing enterprises and financial institutions will start to use ‘cloud', and cloud computing will increase the efficiency of technology and finance," Hu told Xinhua in Davos.

    When you think back to the blackboard from your school days, what color is it? Chances are that it's green. So what's up with the name? Originally, blackboards were really black. Before wall-sized blackboards existed, late 18th-century students used their own mini boards made of slate (石板) or painted wood, according to Concordia University, Those first boards were, in fact, black, and they paved the way for the larger ones.

    In 1800 when a Scottish headmaster named James Pillans wanted his students to draw maps, the students couldn't draw the maps their teacher wanted on their tiny boards, so Pillans put several slates together to create a large board. Problem solved! From there, the idea spread quickly as teachers could finally show a concept to the whole class at one time. By 1815, the massive writing spaces were common enough to earn their own name: blackboard.

    The color change came in the 1960s when companies sold, steel plates, coated with green enamel (漆) instead of the traditional dark slate. The new material was lighter and less fragile than the first blackboards, so they were cheaper to ship and more likely to survive the journey. Teachers weren't complaining either. After all, the new "greenboards" made the chalk powder easier to erase. Plus, the enamel left less of a glare and the color was nicer to look at. At that point, people started using the word "chalkboard "as a more accurate descriptor, but "blackboard" still stuck around.

    For some people, music is no fun at all. About four percent of the population is what scientists call "amusic." People who are amusic are born without the ability to appreciate music or recognize musical notes (音调). Amusic people often cannot tell the difference between two-songs. Amusics can only hear the difference between two notes if they are far apart on the musical scale.

    As a result, songs sound like noise to an amusic. Many amusics compare the sound of music to pieces of metal hitting each other. Life can be hard for amusics. Their ability to enjoy music sets them apart from others. It can be difficult for other people to identify with their condition. In fact, most people cannot begin to understand what it feels like to be amusic. Just going to a restaurant or a shopping mall can be uncomfortable or even painful. That is why many amusics intentionally stay away from places where there is music. However, this can result in withdrawal and social isolation. "I used to hate parties," says Margaret, a seventy-year-old woman who only recently discovered that she was amusic. By studying people like Margaret, scientists are finally learning how to identify this unusual condition.

    Scientists say that the brains of amusics are different from the brains of people who can appreciate music. The difference is complicated, and it doesn't involve defective hearing. Amusics can understand other nonmusical sounds well. They also have no problems understanding ordinary speech. Scientists compare amusics to people who just can't sec certain colors.

    Many amusics are happy when their condition is finally diagnosed (诊断). For years, Margaret felt embarrassed about her problem with music. Now she knows that she is not alone. There is a name for her condition. That makes it easier for her to explain. "When people invite me to a concert, I just say, 'No thanks. I'm amusic,'" says Margaret. "I just wish I had learned to say that when I was seventeen and not seventy."