Here is a record of the discussion about AI (artificial intelligence) conducted by several scientists:

    Scientist A: I would say that we are quite a long way off developing the AI, though I do think it will happen within the next thirty or forty years. We will probably remain in control of technology and it will help us solve many of the world's problems. However, no one really knows what will happen if machines become more intelligent than humans. They may help us, ignore us or destroy us. I tend to believe AI will have a positive influence on our future lives, but whether that is true will be partly up to us.

    Scientist B: I have to admit that the potential consequences of creating something that can match or go beyond human intelligence frighten me. Even now, scientists are teaching computers how to learn on their own. At some point in the near future, their intelligence may well take off and develop at an ever-increasing speed. Human beings evolve biologically very slowly and we would be quickly substituted. In the short term, there is the danger that robots will take over millions of human jobs, creating a large underclass of unemployed people. This could mean large-scale poverty and social unrest. In the long term machines might decide the world would be better without humans.

    Scientist C: I'm a member of the Campaign to Stop Killer Robots. Forget the movie image of a terrifying Terminator stamping on human skulls and think of what's happening right now: military machines like drones, gun turrets and sentry robots are already being used to kill with very little human input. The next step will be autonomous “murderbots” following orders but finally deciding who to kill on their own. It seems clear to me that this would be extremely dangerous for humans. We need to be very cautious indeed about what we ask machines to do.

    A young man was walking through a supermarket to pick up a few things when he noticed an old lady following him around. Thinking nothing of it,he ignored her and continued on. Finally, he went to the checkout line, but she got in front of him. “Pardon me,” she said, “I'm sorry if my staring at you has made you feel uncomfortable. It's just that you look just like my son who just died recently.”

    “I'm very sorry,” replied the young man, “Is there anything I can do for you?”

    “Yes,” she said, “As I'm leaving, can you say ‘Goodbye mother'? It would make me feel much better”. “Sure,” answered the young man.

    As the old lady was leaving the counter, he called out from behind her, “Goodbye mother!” As he stepped up to the checkout counter and put what he bought on the counter, he saw that his total was $127.5. “How can that be?” he asked, “I only bought a few things!”

    “Your mother said that you would pay for her.” said the clerk.

    Although the idea of "zero emission net carbon-positive, sustainable (可持续)" development was promoted worldwide, most cities are at a loss what to do or even some have objected to it. But in Liuzhou, a city in southern China, attitudes could not be more different.

    The Liuzhou Municipality Urban Planning Bureau has signed up Italian architect Stefano Boeri, the father of the forest city movement, to build a self-contained community for up to 30, 000 people. He is the go-to man for such projects thanks to the success of his "vertical forests", two residential (住宅的) towers. Completed in 2014, they remove up to 17.5 tons of soot (煤烟) from the air each year, and a year later one of them was named Best Tall Building Worldwide.

    The Liuzhou project is a much more ambitious undertaking, however. Its homes, hospitals, hotels, schools and offices will be built on a 340-acre site in what Boeri calls the first attempt to create an "urban environment that is really trying to find a balance with nature". Its 100 species of plant life are expected to absorb almost 10, 000 tons of carbon dioxide and 57 tons of pollutants per year, while at the same time producing 900 tons of life-giving oxygen.

    Although the architects haven't published the cost of the forest city, the Milan towers cost only five percent more than traditional skyscrapers.

    The construction of his forest city at Liuzhou is set to begin in 2020, and there is still a great deal of planning and research required before a projected completion date can be set. However, Boeri remains optimistic about the project and has confidence in the soundness of his vision: "I really think that bringing forests into the city is a way to deal with global warming."

    The view you adopt for yourself significantly affects the way you lead your life. It can determine whether you become the person you want to be and whether you achieve the things you value. How does this happen? How can a simple belief have the power to transform your psychology and, as a result, your life?

    Believing that your qualities are carved in stone­the fixed mindset­creates an urgency to prove yourself over and over. Some of us are trained in this mindset from an early age. Even as a child, I was focused on being smart, but the fixed mindset was really stamped in by Mrs. Wilson, my sixth­grade teacher. She believed that people's IQ scores told the whole story of who they were. We were seated around the room in IQ order, and only the highest­IQ students could be trusted to collect homework, or take a note to the principal. She was creating a mindset in which everyone in the class had one consuming goal­look smart, don't look stupid.

    I've seen so many people with this one consuming goal of proving themselves­in the classroom, in their careers, and in their relationships. Every situation calls for a confirmation of their intelligence, personality, or character. Every situation is evaluated: Will I succeed or fail? Will I look smart or stupid? Will I feel like a winner or a loser?

    But doesn't our society value intelligence, personality, and character? Isn't it normal to want these qualities? Yes, but...

    There's another mindset, the growth mindset, which is based on the belief that your basic qualities are things you can develop through your efforts. Although people may differ in every which way­in their inborn talents, interests, or characters­everyone can change and grow through efforts and experience. Did you know that Darwin and Tolstoy were considered ordinary children? That the photographer Cindy Sherman, who has been on almost every list of the most important artists of the twentieth century, failed her first photography course? That Geraldine Page, one of our greatest actresses, was advised to give it up for lack of talent?

    You can see how the belief that valuable qualities can be developed creates a passion for learning. Why waste time proving how great you are, when you could be getting better? Why hide weaknesses instead of overcoming them? And why seek out the tried and true, instead of experiences that will stretch you? The passion for stretching yourself and sticking to it, even when it's not going well, is the feature of the growth mindset. This is the mindset that allows people to achieve success during some of the most challenging times in their lives.

Anew study suggests that Medicare could spend billions of dollars on screening (拍片检查) smokers for lung cancer that would be better spent on helping them quit and keeping others from starting.

The new study indicated that screening more often supported smokers' beliefs that they could safely continue to smoke. Most participants remained smoking because they believed screening could catch cancer early before it would threaten their lives.

"They compared how hard it was to quit smoking with how easy it was to be screened," said Steven B. Zeliadt, the lead author of the study." They engaged in magical thinking that now there's this wonderful painless external test that can save lives."

He and seven colleagues conducted the study of 37 current smokers who were offered lung cancer screening at Department of Veteran Affairs. After being screened and told the results, they were interviewed about their smoking-related heath beliefs. For about half of those, cancer was not found." Screening lowered their motivation for quitting," the team reported in July in JAMA Internal Medicine. The participants focused only on lung cancer, ignoring other potential harm of smoking.

A national study published four years ago found that annual CT screening for lung cancer three years in a row could reduce deaths among heavy smokers by about 20 percent. In an interview, Dr. Russell P. Harris, a preventive medicine specialist at the UNC-Chapel Hill, noted that" Screening is being believed by people as an alternative to stopping smoking. But stopping smoking would have huge benefits for the individual and society." Furthermore, smoking causes many other cancers.

Dr. Harris agreed that rather than screening, money is better spent on smoking prevention. He suggested providing free stop-smoking aids, sponsoring anti-smoking advertising and raising taxes on tobacco products and the age at which people are allowed to buy them.

In San Francisco, a large group of sea lions move themselves out of the bay waters and hang out on PIER 39, which is a popular tourist destination. According to dock（码头）officials, this is the most sea lions seen in the region in 15 years.

"Over 1,000 sea lions have been counted this week," PIER 39 harbormaster Sheila Chandor told many different media. "The surge in sea lions is usually a good sign of their strong population and healthy living environment," said Adam Ratner, Director of Conservation Engagement at the Marine Mammal（海洋哺乳动物）Center in Sausalito, California.

"California sea lions are sentinels（哨兵）of the ocean," Ratner said. Their population to some extent reflects the health of the ocean. Therefore, seeing a large number of California sea lions is clearly a good thing.

For nearly 35 years, the slippery（滑的）residents have been a star attraction for tourists. That autumn in 1989, PIER 39 had just been repaired, but the ships had not yet been moved back. At that moment, the sea lions' unexpected arrival not only attracted fans but also created enemies. According to a website, some dock residents and workers were scared away by the strong and very unpleasant smell and noise of their new neighbors, while others saw these animals as a bright spot after the destructive Loma Prieta earthquake.

The officials sought help from the Marine Mammal Center to find a way to deal with sea lions. Ratner said that the final decision is to let the sea lions stay and coexist with humans. "The fact proves that this is really a good thing," he said. "This is just a proof of how we can truly work together and think about how we can share our coasts with marine mammals and other wildlife in a way that benefits all the parties involved."