1 . On March 7, 1907, the English statistician Francis Galton published a paper which illustrated what has come to be known as the “wisdom of crowds” effect. The experiment of estimation he conducted showed that in some cases, the average of a large number of independent estimates could be quite accurate.

This effect capitalizes on the fact that when people make errors, those errors aren’t always the same. Some people will tend to overestimate, and some to underestimate. When enough of these errors are averaged together, they cancel each other out, resulting in a more accurate estimate. If people are similar and tend to make the same errors, then their errors won’t cancel each other out. In more technical terms, the wisdom of crowds requires that people’s estimates be independent. If for whatever reasons, people’s errors become correlated or dependent, the accuracy of the estimate will go down.

But a new study led by Joaquin Navajas offered an interesting twist (转折) on this classic phenomenon. The key finding of the study was that when crowds were further divided into smaller groups that were allowed to have a discussion, the averages from these groups were more accurate than those from an equal number of independent individuals. For instance, the average obtained from the estimates of four discussion groups of five was significantly more accurate than the average obtained from 20 independent individuals.

In a follow-up study with 100 university students, the researchers tried to get a better sense of what the group members actually did in their discussion. Did they tend to go with those most confident about their estimates? Did they follow those least willing to change their minds? This happened some of the time, but it wasn’t the dominant response. Most frequently, the groups reported that they “shared arguments and reasoned together”. Somehow, these arguments and reasoning resulted in a global reduction in error. Although the studies led by Navajas have limitations and many questions remain, the potential implications for group discussion and decision-making are enormous.

Jean’s dream was to be a great chef, so when she was 20, she travelled to France, which has the most famous cuisine in the world, to learn to cook. After twelve years, she was among the best.

Her father, Bob, was getting old, and she wanted to be near him. Jean accepted an offer from one of Washington’s top restaurants. The manager offered her a handsome salary, and 30% ownership of the restaurant. The next day, Jean went to sign the contract. As she got out of the car, she caught sight of a green sunshade. Instead of going to meet the manager, she crossed the street towards the old restaurant, Fargonetti’s. She pushed open the door and the memories came flooding back.

Jean’s mum died when she was just 11, and her father lost his job and was forced to freelance (从事自由职业). Money was very short. When Jean turned thirteen, Bob had made a reservation at Fargonetti’s, the capital’s best restaurant.

“I’m not hungry, baby girl. I had a huge breakfast,” Bob said. “This is all for you!” “Oh,” Jean cried. “Daddy was so silly! He’s been saving to come here for lunch for MONTHS and now he ruined his appetite with breakfast!” The waiter, Carl Bader, immediately realised what was going on and went to Mr Fargonetti, the restaurant owner, and told him about Jean and Bob.

An hour later, surprisingly, the waiter brought wonderful dishes and set them before the father and daughter. “Lunch is on the house with Mr Fargoneti’s compliments (致意),” Carl said. For Bob and Jean, it was a free but magical meal. They were on cloud nine when they walked out. “Jean,“ said Bob happily. “I feel our luck has changed!” And it did! The next day, one of Bob’s old friends called and offered him a job at a new magazine, and Jean believed Fargonetti’s had made it all happen. That was when she decided to become a chef!

Twenty years later, the old restaurant looked run-down and sad, but Jean recognised the waiter immediately. “Carl?” she asked delightedly.

The man looked surprised.

Jean was staring at Carl and a brilliant idea was taking shape in her mind.

I was invited to a cookout on an old friend’s farm in western Washington. I parked my car outside the farm and walked past a milking house which had apparently not been used in many years. A noise at a window caught my attention, so I entered it. It was a hummingbird (蜂鸟), desperately trying to escape. She was covered in spider-webs (蛛网) and was barely able to move her wings. She ceased her struggle the instant I picked her up.

With the bird in my cupped hand, I looked around to see how she had gotten in. The broken window glass was the likely answer. I stuffed a piece of cloth into the hole and took her outside, closing the door securely behind me.

When I opened my hand, the bird did not fly away; she sat looking at me with her bright eyes. I removed the sticky spider-webs that covered her head and wings. Still, she made no attempt to fly. Perhaps she had been struggling against the window too long and was too tired? Or too thirsty?

As I carried her up the blackberry-lined path toward my car where I kept a water bottle, she began to move. I stopped, and she soon took wing but did not immediately fly away.

Hovering (悬停), she approached within six inches of my face. For a very long moment, this tiny creature looked into my eyes, turning her head from side to side. Then she flew quickly out of sight.

During the cookout, I told my hosts about the hummingbird incident. They promised to fix the window. As I was departing, my friends walked me to my car. I was standing by the car when a hummingbird flew to the center of our group and began hovering. She turned from person to person until she came to me. She again looked directly into my eyes, then let out a squeaking call and was gone. For a moment, all were speechless. Then someone said, “She must have come to say goodbye.”

A few weeks later, I went to the farm again.

I was just about to leave when the hummingbird appeared.

I needed to do something in my community (社区) in order to complete the community service hours required to graduate from high school. Some of my friends had signed up to spend time at a soup kitchen, so I did, too. It seemed like a good thing to do.

I thought that we would just be passing out dinners to those in need, but I found out we would be doing everything from preparing to serving the dinner. We began preparing the food, from mixing salad dressing to separating frozen meat. Much still needed to be done before dinner was served, but already outside the building many homeless people were gathering. It wasn’t until a couple of hours later that we opened the doors and began serving dinner.

As the line of people came toward me, I got a little scared. I’d come face to face with the homeless: How should I act? How would they treat me? Would they hate me for having more than they did? While some of the people looked very friendly, some of them looked so dangerous. I didn’t have too much time to worry about it. I was assigned (分配) to serve the salad with the lady next to me. She smiled at me and said if I needed help, she’d be right there, which I found quite comforting.

I had never seen so many people wanting food. They were of all ages and nationalities. Most of them wore clothes that were torn and dirty. Some looked like they had tally given up on life, while others seemed to be making the best of the situation, smiling and joking. Some were better off than others, but they all needed a good meal and a warm place to eat. It saddened me to think of how many people there were who didn’t have a place to call home and the only food they got came from a soup kitchen.

As they came in my direction, I put on my brightest and happiest smile.

I was so happy that I had earned my service hours in this way.

6 . Hundreds of scientists, writers and academics sounded a warning to humanity in an open letter published last December: Policymakers and the rest of us must engage openly with the risk of global collapse. Researchers in many areas have projected the widespread collapse as “a credible scenario(情景) this century”.

A survey of scientists found that extreme weather events, food insecurity, and freshwater shortages might create global collapse. Of course, if you are a non-human species, collapse is well underway.

The call for public engagement with the unthinkable is especially germane in this moment of still-uncontrolled pandemic and economic crises in the world's most technologically advanced nations. Not very long ago, it was also unthinkable that a virus would shut down nations and that safety nets would be proven so disastrously lacking in flexibility.

The international scholars’ warning letter doesn't say exactly what collapse will look like or when it might happen. Collapseology, the study of collapse, is more concerned with identifying trends and with them the dangers of everyday civilization. Among the signatories(签署者) of the warning was Bob Johnson, the originator of the “ecological footprint” concept, which measures the total amount of environmental input needed to maintain a given lifestyle. With the current footprint of humanity, “it seems that global collapse is certain to happen in some form, possibly within a decade, certainly within this century,” Johnson said in an email.

“Only if we discuss the consequences of our biophysical limits,” the December warning letter says, “can we have the hope to reduce their speed, severity and harm”. And yet messengers of the coming disturbance are likely to be ignored. We all want to hope things will turn out fine. As a poet wrote,

Man is a victim of dope(麻醉品)

In the incurable form of hope.

The hundreds of scholars who signed the letter are intent(执着) on quieting hope that ignores preparedness. “Let's look directly into the issue of collapse,” they say, “and deal with the terrible possibilities of what we see there to make the best of a troubling future.”