ARNOLD Schwarzenegger is back, once again taking on his iconic killer robot role, the T-800, in August's new movie Terminator Genisys. While the T-800 model—even if it can be evil—has a fond place in moviegoers' hearts, the reality of autonomous machines is no joke, according to scientists.

    Autonomous weapons use artificial intelligence (AI) to choose targets without human help. They were described as “the third revolution in warfare, after gunpowder and nuclear arms” in an open letter signed by over 1,000 important technology figures in July. The list included British scientist Stephen Hawking and Apple co-founder Steve Wozniak. They asked governments around the world to ban autonomous weapons, warning that killer robots could start ethnic cleansings and an arms race.

     “They will look like tanks. They will look like battleships. They will look like jet fighters,” UK robotics professor Noel Sharkey told CNET, a leading technology website.

    But unlike these machines, which require a human hand in their action, so-called “killer robots” would have some decision-making abilities and the ability to act on their own.

     “If any major military power pushes ahead with AI weapon development, a global arms race is almost inevitable,” said the letter released at the 2015 International Joint Conference on Artificial Intelligence in Buenos Aires, Argentina.

    The idea of an automated killing machine was made famous by Schwarzenegger's first Terminator movie in 1984. While no red-eyed robots have been sent after human beings, the idea of AI being used as a weapon has gotten much more likely in the years ever since. The US military is already developing autonomous flying vehicles that can carry out all the steps of a strike mission without a human controlling them, according to a May report in Nature magazine.

    Scientists have even painted a destructive picture of autonomous weapons falling into the hands of terrorists or warlords hoping to carry out ethnic cleansings.

     “The development of full artificial intelligence could lead to the end of the human race,” Hawking said to the BBC in 2016.

Authorities are gradually waking up to the risk of robot wars. Last May, for the first time, the United Nations brought governments together to begin talks on autonomous weapons systems.

    Still, a ban on autonomous weapons is “easier said than done”, commented The Guardian. The dual (双重的) uses of the AI technology—for harm and for good—is difficult to manage. This is because the exact same technology can be used in a wide range of ways, the paper said.

    Whether you are young or young at heart, it is never too late to change, or take in some new and better practices into your daily life. Here are some wise lessons that I wish I knew when I was younger.

    I used to be worried about what others thought of me. Finally, I changed. Remember that if you're wasting too much time looking for respect(尊重) from others, then you will not have time to finish all you desire(期望).Everyone has an opinion, but in fact others' opinions about you are based more on their history and perceptions(观念) than anything you're actually doing. So depend on your own assessment(评估) of you rather than others'.

    Enjoy every moment of today. Don't wait to do or enjoy anything. Don't tell yourself you will do it tomorrow. If it is important to you, then do it today. Pay attention to what is happening now, the task at hand and all the choices you make today, big and small. Our future is set by what we decide and do today.

    What happened yesterday is over. You can not change it. So let it go. Don't waste your energy considering anger or unhappiness. It only stops you from moving forward in life.

    Look for the good in people. Celebrate the happy moments, big and small. Search for the chances for growth. Give helpful encouragement rather than unwanted criticism (批评). Be helpful whenever possible.

    In a word, life is serious but you can still be delighted and hopeful. Otherwise, what's the point?

    If you have spent any time living in or visiting a big city in China, you have most likely used the service that Didi provides. The convenient ride-sharing company, now known as Didi Chuxing, was praised last month by Fortune magazine. According to the magazine, it is changing the world with its environmentally friendly solution to getting around in major cities. As the magazine reported: “Didi concluded that last year its car-pooling services helped reduce total car trips in the country by 1 million a day, which saved 500 million liters of gas, cutting 13.5 million tons of carbon emissions (排放) per day.” The transport service was the only Chinese company to make the important magazine's list, and its influence can be felt in many parts of Chinese society.

    Didi is just one example of what is being called the “sharing economy”. The sharing economy is one in which regular people exchange goods and services, usually using an online marketplace. Other similar companies include companies that allow people to rent out their homes to strangers like Airbnb and Couchsurfing, and similar ride sharing services like Uber and Lyft.

    All of these services are possible partly because many people are realizing that they have underused assets in their lives. Millions of people around the world have started renting them out online to earn extra money. They rent their apartments while they are away for the weekend, lend people their cars for money and even sell their spare time.

    The sharing economy is the latest example of the Internet's value to customers. This model is now big enough for regulators and companies to have woken up to it. That is a sign of its great potential. It is time to start caring about sharing.

    The American Academy of Pediatrics (AAP) (儿科学) just released its updated guidelines for children's media use.

    The recommendations reflect what all parents know: children need less screen time, which indicates that they desperately need more free time to develop their imagination, a sense of wonder and discover their passion and purpose.

    Our children are over-stimulated, over-scheduled and under pressure to perform academically and beyond school. This weakens their ability to build creative thinking skills essential to self-discovery. Creativity occurs when kids have time for curiosity and exploration. With children spending up to eight hours a day on media devices and additional hours engaging in scheduled activities, opportunities for growth disappear.

    What we are not so sure about is how to get our kids to want the free, screenless time which we know will benefit them. It may sound counter-intuitive (违背直觉的) but today's kids need coaching to experience and discover the benefits of free time.

What came to parents easily a few decades ago has become a challenge for our generation. It's not that yesterday's parents knew more about child development; they simply had fewer choices. Boredom and relaxation were an inescapable part of daily life. Today, they mean, "I'm a bad parent and not doing enough to get my kid ahead."

    Recently, I had an eye-opening revelation while watching my 11-year-old daughter play in a softball game. I have six children and have attended dozens of such game. I know the drill—or thought I did. Families settled in for the day with lawn chairs, cold drinks and cousins. These brothers and sisters would gradually chat with each other. Games of catch and hide-and-seek began, and friendships were formed then. At crucial moments, the newfound friends turned their attention to the field to cheer on their teams.

    But that wasn't happening. Though there were at least 15 children by the sidelines (球场边线), I didn't hear any of them. They sat in silence using their individual tablets (平板电脑). Even with the score tied in the final inning (垒球比赛的一局), not a single child watched the game or spoke to each other. The situation was strange and revealing: Kids have more planned activities and passive entertainment at their fingertips than ever before, but less free time to dream, imagine and focus on what they truly love.

I understand that making time for "nothing" is difficult in a world where we are constantly worried our kids will fall behind if they aren't good at academics. But I refuse to sit back and watch this loss of childhood. We are taking back childhood. Imagination needs time and space to blossom.

If your kids are like mine, asking them to imagine will at the beginning be difficult. That's because they haven't developed the skills and muscle memory to make it second nature. I hope the AAP guidelines prompt all of us to set needed screen time limits for our children. Personally, I am practicing strategies to "develop imagination" in my children. Imagination, like a sport, requires practice, training, motivational speeches, rewards and extreme patience.

    Twelve years ago, I was a 19 -year-old guy living in the French A1ps. In February 2004, while skiing the back - country in Val d'Isere, I fell off the mountain, resulting in a right leg broken in several pieces. I was helicoptered to hospital, operated on immediately—and there started my adult life.

    Before the accident, I was on a path to what I hoped would be a career in rugby. After-wards, and participation in collision sport was gone. I found a replacement in cycling. Unfortunately, by late 2012, I tried to cycle up Mount Ventoux, but it was halfway up when the pain hit me and I gave up.

    A decision needed to be made on a next step. I had to have my lower right leg cut off. Several months later, I had my first proper weight - bearing prosthetic (假肢). I jumped on a train with my bike to Mount Ventoux. Though it certainly wasn't my quickest, I did it.

    Two weeks later, I was lucky enough to be given a running blade; I bounced on it that day and then raced my triathlon (三项全能) on the Monday. So, that was me, up and running - almost 12 years since I had last run.

    Along with my running coach, I complete a “make every kilometre count” programme of four runs per week alongside a busy cycle, swim and gym schedule. So far this year, I have raced a 10k with an unexpected personal best in January of 38:04. I have my first speed triathlon in late March before heading to North Korea to compete in the Pyongyang Marathon on 10 April.

    If my lifetime allows, I will attempt to race in every country in the world. In the meantime, I'll keep on running — and, when it hurts and I'm low on motivation, I'll remember how far I've come and how much further I've got to go.

    What's best to read this year?

    Secrets I Know (Random House Children's Books, ages 3-7)

    This tale written by Kallie George and pictured by Paola Zakimi follows a young girl and her little friend as they move from rain to sunshine, from pleasant loneliness to sweet friendship, and finally from adventures on earth to an exploration of the sky above. The colors of Zakimi's pencildrawings are calming and George's poetic text tells her story with simple language.

    Pandora (Clarion Books, ages 3-7)

    The award-winning author Victoria Turnbull tells the story of a little fox Pandora. Pandora lives alone. She makes herself a handsome home, but no one ever comes to visit. Then one day something falls from the sky -- a bird with a broken wing. Little by little, the bird helps Pandora feel less lonely. Turnbull's watercolor and colored pencil drawings make this story of friendship and growth an atmospheric delight.

    Prince and Pirate (G.P. Putnam's Sons Books for Younger Readers, ages 5-8)

    A different kind of friendship is described in this book, by Charlotte Gunnufson with pictures by Mike Lowery. Prince and Pirate are a pair of mismatched fish put into the same aquarium（水族馆). At first it seems that they'll never learn to be friends. It's only when both take pity on a frightened dogfish that they learn the benefits of cooperation, and soon all three fish become good friends.

    The Giant Jumperee (Dinal Books, ages 3-5)

    The story was written by the award-winning British author Julia Donaldson. When Rabbit hears a loud voice bellowing（吼叫）threateningly from inside a cave, he gathers Cat, Bear and Elephant to help him decide what to do. But it's Mama Frog who fearlessly confronts（面对）the unknown creature. Helen Oxenbury's soft watercolors creat a beautiful countryside and her characterizations of the animals are impressive.