1 . Ariel Procaccia has thought a lot about how to cut a cake over the last 15 years. As the father of three children, he knows how hard it is to divide a birthday cake to everyone’s satisfaction. But it’s also because Procaccia’s work focuses on exploring the mathematical rules for dividing stuff up fairly. One way to do that is to think abstractly about dessert.

For decades, researchers have been asking the seemingly simple question of how to cut a cake fairly. The answer reaches far beyond birthday parties. A mathematical problem at its heart, cake cutting connects strict reasoning to real-world issues of fairness, and so attracts not only mathematicians, but also social scientists, economists and more. “It’s a very elegant model in which you can distill what fairness really is, and reason about it,” Procaccia says.

The simplest approach is called the “divider-chooser” method, where one person cuts the cake into two equal pieces in his view, and the other person picks first. Each receives a piece that they feel is as valuable as the other’s. But when personal preferences are taken into account, even the easiest rule becomes complicated. Suppose Alice and Bob are to divide a cake, and Alice knows Bob prefers chocolate, she may knowingly divide the cake unequally so the smaller piece contains more chocolate. Then Bob will choose according to his preference, and Alice will get the larger piece. Both of them are satisfied with what they get, but the meaning of fairness changes in this situation.

The cake is a symbol for any divisible good. When cake-cutting principles are employed to settle disagreements, they are potentially helping the world find solutions. Procaccia has used fair division algorithms (算法) to model food distribution. Social scientist Haris Aziz is exploring situations ranging from how to divide up daily tasks to how to best schedule doctors’ shifts in hospitals.

Even after decades of investigation, cake cutting isn’t like a simple jigsaw puzzle (拼图) with a well-defined solution. Instead, over time, it has evolved into a kind of mathematical sandbox, a constructive playground that brings together abstract proofs and easy applications. The more researchers explore it, the more there is to explore.

3 . Hiring processes can be thought of as a battle between integrity and dishonesty. You might imagine this is a simple fight between truth-seeking firms and self-promoting candidates, and to a certain extent it is. But companies themselves are prone (有倾向的) to bend reality out of shape in ways that are self-defeating.

Start with the obvious wrongdoers: job applicants. When it comes to writing the resume (简历), they tend to massage (美化) reality into the most appealing shape possible. Everyone beyond a certain level of experience is a transformational leader personally responsible for generating millions income; the world economy would be about 15 times bigger than it actually is if all such claims were true. The average British spends four and a half hours a day watching TV and online videos. But each average job candidate is an enthusiast for public welfare, using their spare time only for worthy purposes, like volunteering in soup kitchens.

But the tendency to stretch the truth infects companies as well as applicants. The typical firm will write a job description that invariably describes the work environment as fast-paced and innovative, and then lays out a set of improbable requirements for the “ideal candidate”, someone who almost by definition does not exist. Sometimes, the requirements include an ability to go back and change the course of history.

Too few firms offer an accurate account of what a position actually involves in their job previews, which are supposed to give prospective employees a genuine sense of the negatives and positives of the job, as well as a clear idea of the company’s corporate culture. One effective strategy is to lay out in text or video, what a typical day in the role would look like.

Such honesty can be its own reward. Research has long suggested that realistic job previews lead to lower turnover and higher employee satisfaction. A paper in 2011 by David Eamest of Towson University and his co-authors concluded that favourable perceptions of the organisation’s honesty are the best explanation for why. So a process designed to uncover the truth about job applicants would run a lot more smoothly if firms were also honest about themselves.

5 . Nowadays, people are increasingly interacting with others in social media environments where algorithms control the flow of social information they see. People’s interactions with online algorithms may affect how they learn from others, with negative consequences including social misperceptions, conflict and the spread of misinformation.

On social media platforms, algorithms are mainly designed to amplify (放大) information that sustains engagement, meaning they keep people clicking on content and coming back to the platforms. There is evidence suggesting that a side effect of this design is that algorithms amplify information people are strongly biased (偏向的) to learn from. We call this information “PRIME”, for prestigious, in-group, moral and emotional information.

In our evolutionary past, biases to learn from PRIME information were very advantageous: Learning from prestigious individuals is efficient because these people are successful and their behavior can be copied. Paying attention to people who violate moral norms is important because punishing them helps the community maintain cooperation. But what happens when PRIME information becomes amplified by algorithms and some people exploit (利用) algorithm amplification to promote themselves? Prestige becomes a poor signal of success because people can fake prestige on social media. News become filled with negative and moral information so that there is conflict rather than cooperation.

The interaction of human psychology and algorithm amplification leads to disfunction because social learning supports cooperation and problem-solving, but social media algorithms are designed to increase engagement. We call it functional mismatch. One of the key outcomes of functional mismatch is that people start to form incorrect perceptions of their social world, which often occurs in the field of politics. Recent research suggests that when algorithms selectively amplify more extreme political views, people begin to think that their political in-group and out-group are more sharply divided than they really are. Such “false polarization” might be an important source of greater political conflict.

So what’s next? A key question is what can be done to make algorithms facilitate accurate human social learning rather than exploit social learning biases. Some research team is working on new algorithm designs that increase engagement while also punishing PRIME information. This may maintain user activity that social media platforms seek, but also make people’s social perceptions more accurate.

6 . Humanities departments(人文院系)in America are once again being cut down. Earlier this month, the State University of New York(SUNY)StonyBrook announced a plan to abandon several of the college’s well-known departments for lack of fund. The University of Pittsburgh has cut its German and classics.     1    In the UK, Middlesex University decided to gradually get rid of philosophy department. In June 2015, the Japanese minister of education sent a letter to the presidents of the national universities of Japan, suggesting they close their graduate and undergraduate departments in the humanities and social sciences and focus on something more practical.

These are hard times. Instead of Shakespeare or French, there will be(perhaps there already are)college classes in how to cut corporate spending.     2    But the only opportunity has been lost if they are denied the opportunity to study foreign languages, the classics, literature, philosophy, music, theater and art in the university. When else in their busy lives will they get that chance?

    3    . Essays explain why we need these subjects, and what their loss will mean. These areas of learning provide us with the ability to think critically and independently; to see both sides of an issue;to look beneath the surface of what we are being told; to appreciate the ways in which language can help us understand one another more clearly.

I don’t believe that the humanities can make you a decent person.     4    . Studying philosophy teaches us about those who have gone before us. A foreign language brings us closer to those with whom we share the planet. The humanities touch those aspects of awareness that we call intellect and heart.     5    

8 . Danone Portugal introduced a new yogurt named Juntos. For every pack of yogurt that a person bought, he would donate yogurt to a family in need. Danone had done its research. Increasingly, people say they want to buy from brands that give them a sense of purpose. Surely a yogurt that helped the needy would be appealing. But Juntos was a failure. Despite sinking millions into a marketing campaign, Danone pulled Juntos from the market only months after it was launched. Now the same product is simply marketed as a tasty yogurt.

What happened? To find the reason behind Juntos’ failure, Lawrence Williams and his colleagues did an experiment where they showed people some products and asked these people to pick one option. They reminded some to focus on the “purposeful and valuable” aspect while others were told to “enjoy themselves” and focus on “delight and pleasure.” They found that participants who prioritized meaning preferred the less expensive product when compared with people who put pleasure in the first place.

So why were meaning-seekers cheaping out? Lawrence Williams asked participants to explain their decision-making to find out. He learned that meaning-oriented people were not thinking about how the product they might buy could bring meaning to their lives. Instead, they were occupied with what else they could do with their money.

I am all for people making wise and strategic financial choices. But cheap products can create many problems. Inexpensive options often do not last as long as the higher-end ones. As a result, we shop more often, which is ultimately worse for our wallets. Plus, that spending pattern can do a greater damage to the environment. Thanks in part to fast fashion, people buy 60 percent more clothing today than they did 15 years ago. The fashion industry alone emits more greenhouse gases than international flights and maritime (海洋的) shipping combined.

So before you dive into your wallet for some deals, try not to fix only on what you are spending or saving. Think carefully about what you are buying, too.

9 . There is no universally accepted age that is considered old among or within societies. Often disagreements exist as to what age a society may consider old and what members in that society of that age and older may consider old. Moreover, biologists are not in agreement about the existence of an internal biological cause foraging.

In general the social status of an age group is related to its effective influence in its society, which is associated with that group’s function in productivity. In agricultural societies the elderly have a status of respectability. Their life experiences and knowledge are regarded as valuable, especially in preliterate (尚无文字的) societies where knowledge is orally transmitted. The range of activities in these societies allows the elderly to continue to be productive members of their communities.

In industrialized nations, although in certain fields old age is still considered significant, particularly in the political field, older people are increasingly being forced into retirement before their productive years are over, causing problems in their psychological adaptations to old age. Retirement is not regarded unfavorably in all instances, but its economic limitations tend to further remove older people from the range of influence and raise problems in the extended use of leisure time and housing. As a consequence, financial preparation for retirement has become an increased concern for individuals and society.

Familial relationships tend to be the focus of the elderly’s attention. However, the tendency for young people in industrialized countries to be highly mobile has forced older people to decide whether to move to keep up with their families or to remain in neighborhoods which also change, altering their familiar patterns of activity. Although most older people do live within an hour from their closest child, industrialized societies are faced with formulating programs to accommodate increasing numbers of older people who function independently of their families. Adult education programs are beginning to close the generation gap; however, as each successive generation reaches old age, bringing with it its particular tendencies and preferences, new problems arise requiring new social accommodations.

10 . The UN this week launched a report urging companies to stop issuing false net-zero targets that amount to greenwashing.

Greenwashing is a term used to describe situations where companies mislead consumers by claiming to be eco-friendly or sustainable as a marketing plan rather than as a core principle of their business model. Often, these industries spend more money making themselves appear sustainable than they do taking actual sustainable measures into their company.

Cities, financial institutions, and scores of companies have announced plans to reduce their emissions to zero, which, in principle, should help the fight against climate change.

“The problem is that the criteria for these net-zero commitments have varying levels of precision and loopholes (漏洞),” said UN Secretary-General Antonio Guterres during the launch of the report.

Many net-zero plans contain far-away or unclear targets and often call for the use of unproved technologies like carbon capture and tree planting, which effectively allow companies to continue polluting the atmosphere. Studies show that most of these net-zero plans will do little to stop temperatures from rising. For example, many oil majors have announced plans to reduce emissions from their operations to zero by 2050 that do not take into account the carbon emitted by the fossil fuels they sell, which would allow them to increase production. Far from decreasing, fossil fuel production is going strong.

To close these net-zero loopholes, the UN this week released a report that includes 10 recommendations to ensure that companies, cities, regions, and other non-state actors issue credible and accountable net zero commitments. “Their plans cannot rely on cheap carbon credits instead of immediately cutting their own emissions,” Guterres said.

Financial institutions need to cut down emissions from all their investments and businesses need to bring down the carbon footprint of their supply chain, the report said. The report’s lead author, Catherine McKenna, urged companies to release new net-zero targets within a year. The updated targets must contain concrete actionable details.