Yanwen’s blog

7/22/2026

On Monday, I spent hours trying to resolve an issue with Verizon's customer service, but got nowhere. Frustrated, we ended up visiting a Verizon store the following day.

While standing outside the store, I noticed the neighboring stores belonged to Verizon's competitors—Spectrum and T-Mobile. That reminded me of a recent news report describing Verizon's growing challenges from rivals, especially T-Mobile.

For years, Verizon dominated the U.S. telecommunications market. With its vast customer base and extensive network, it seemed almost untouchable. T-Mobile, by contrast, was once the smaller challenger with far fewer resources.

Today, however, the roles appear to be changing. T-Mobile has been steadily gaining market share, while Verizon is facing increasing pressure. Perhaps one day T-Mobile will become the industry leader. If it does, history suggests that another ambitious challenger will eventually emerge to challenge it.

This brings to mind the old Chinese saying: 骄兵必败，哀兵必胜 (Jiāo bīng bì bài, āi bīng bì shèng)—"An arrogant army is destined to be defeated, while an army fighting with determination is more likely to prevail." Or success often breeds complacency and leads to defeat, while challengers are forced to innovate which leads to success.

There seems to be a recurring cycle: the incumbent on the top seat has more to protect, while the challenger has more to prove. Once the challenger reaches the top and becomes the incumbent, the fire that fueled its rise can gradually give way to complacency, creating an opening for the next ambitious challenger.

Perhaps this Chinese saying contains wisdom that goes far beyond the battlefield. Success can breed complacency, while adversity often fuels determination. Whether in business or in life, the greatest challenge is not reaching the top—it is continuing to learn and improve after you get there.

The saying also echoes a central idea in modern psychology: cultivate a growth mindset.

Finally, here's the enduring wisdom behind 骄兵必败，哀兵必胜. Success should be a motivation to keep growing, not a reason to stop.

7/21/2026

A college classmate shared an article with me yesterday about olfactory training, a rehabilitation method for people who have lost or impaired their sense of smell.

The original olfactory training protocol, developed by Thomas Hummel, uses four distinct scents—rose, lemon, eucalyptus, and clove—because each represents a different category of odor. The goal is to expose the olfactory system to a diverse range of chemical stimuli rather than repeatedly smelling similar scents.

Among these four, eucalyptus and clove have an additional feature. Besides stimulating the olfactory system, they also activate the trigeminal nerve, which detects sensations such as cooling, warmth, and mild irritation rather than smell itself.

One remarkable characteristic of the olfactory system is its ability to regenerate. Unlike most neurons in the central nervous system, olfactory receptor neurons are continuously replaced throughout life. This unique capacity is one reason smell rehabilitation is possible.

The most fascinating aspect of olfactory training, however, is the emphasis on conscious recall. Patients are encouraged not merely to smell a lemon, but to actively imagine it—to picture its bright yellow color, remember its fresh citrus aroma, and even recall the sensation of biting into it.

Modern neuroscience suggests that smell is much more than the simple detection of odor molecules. It is a complex cognitive process involving memory, emotion, expectation, previous experience, and focused attention. 

When you smell a cup of coffee, for example, your brain is not just recognizing airborne chemicals. It is simultaneously retrieving memories, emotions, and associations built over a lifetime.

This emphasis on active attention, rather than passive smelling, fits well with what we know about the brain. 

Whether learning a new language, recovering from a stroke, practicing the piano, or rehabilitating the sense of smell, focused and repeated practice is generally far more effective than passive exposure.

That is why many smell specialists encourage patients to do more than simply sniff an odor:

"Don't just smell it. Think about it. Imagine it vividly. Recall the memories it evokes. Pay attention to every faint sensation you experience."

This advice reflects one of the brain's most remarkable abilities—neuroplasticity, its capacity to reorganize and strengthen neural connections through repeated, purposeful practice. Although researchers are still investigating exactly how olfactory training works, the underlying principle is well supported.

What attracted me to this topic is not the treatment of smell loss but the broader insight that active mental engagement can help the brain heal and sharp.

This also makes me wonder whether olfactory training might benefit older adults in ways beyond restoring smell. Because the brain links odors so closely with memory and emotion, perhaps repeatedly recalling familiar scents helps exercise neural pathways associated with the hippocampus. Whether future research confirms this remains to be seen, but it is certainly an intriguing possibility.

So, sniff a fruit, focus your attention, imagine, and activate your hippocampus!

7/20/2026

I read a change in U.S. visa policy for international students. It makes me think a lot about America's greatest advantages. For more than a century, one of America's greatest competitive advantages has not been its natural resources or geography—it has been its ability to attract the world's brightest minds.

Briefly, the new rule is like this. The Department of Homeland Security has finalized a rule that ends the long-standing "duration of status" (D/S) system for F-1 students and J-1 exchange visitors. 

Instead, new entrants will generally receive a fixed period of stay (typically up to four years, or the program length if shorter), and students who need more time must apply for an extension.

The new rule also places additional restrictions on transfers, changes in educational objectives, and shortens the grace period after completing studies.

Many of America's most influential scientists and entrepreneurs were immigrants or international students. Albert Einstein, Sergey Brin, Jensen Huang, Satya Nadella, Andrew Grove, and Elon Musk are all well-known examples.

Likewise, immigrants account for a disproportionately large share of U.S. Nobel Prize winners and founders of major technology companies.

We don't yet know the full consequences of this new rule. However, there are a few things we do know with confidence.

For decades, the United States has benefited from a remarkably successful talent pipeline.

First, America's world-class universities and relatively open immigration policies have attracted talented students from around the world.

Second, many of those students stay to earn advanced degrees, conduct research, or launch innovative companies.

Third, their work contributes to scientific discovery, technological innovation, economic growth, and tax revenue.

If the United States comes to be seen as a less welcoming or less predictable and uncertain place, some of the world's brightest students may increasingly choose Canada, the United Kingdom, Australia, Singapore, or other countries instead, like what happened during World War II when many scientists like Einstein ran into the U.S.

The effects may not be immediately visible. America's leading universities, research institutions, venture capital ecosystem, and entrepreneurial culture remain huge advantages.

The greater risk lies in the long term. If enough highly qualified students begin choosing elsewhere instead of the United States, the U.S. gradually lose part of the talent pipeline that has fueled its innovation for generations.

Those advantages, however, are not self-sustaining. They depend on a continuous inflow of talented people from around the world. Talent is mobile. If the United States becomes less attractive, that pipeline may gradually shrink. Over time they could affect scientific research, technological innovation, and America's global competitiveness.

In the end, people matter more than anything else. America's greatest strength lies in its human capital—its ability to attract talented people from every corner of the world.

A reader comments, “ 如果附加了移民前景的美国教育收窄移民通道，国际学生可能变少，那会带来美国大学的萎缩。” That’ll definitely force some schools to close.

7/19/2026

I recently came across an explanation on the Chinese internet for why the crime rate is so high in the United States: 缺爹 (father absence). I did some research on this. 

Here's what I found:

Father absence is a significant social issue in the United States. Approximately 1 in 4 American children (18.2 million) live without a biological, adoptive, or stepfather in the home—one of the highest rates among developed countries. 

The problem is especially prevalent in the Southern states, with Mississippi having the highest rate. Among major U.S. cities, New York, Chicago, and Newark have historically ranked among those with the highest proportions of fatherless families.

Research consistently shows that father absence is strongly associated with a wide range of social challenges. 

Children growing up without a father in the home are, on average, FOUR times more likely to live in poverty, TWICE as likely to drop out of high school, and face higher risks of behavioral problems, mental health issues, homelessness, substance abuse, juvenile delinquency, and teenage pregnancy. 

These findings suggest that father absence is an important risk factor that often intersects with all kinds of social and economic disadvantages later in life.

Overall, the research underscores the importance of having an involved father in a child's life. While no single factor determines a child's future, ultimately, an engaged father can serve as an important protection against many adverse outcomes later in life.

A reader’s comment: “… 像咱们这样的家庭， 没有父亲的陪伴可能也不会产生问题儿童。但对父亲来说是一大精神和情绪价值的损失。 我父亲就是如此，他工作忙，忽视我们，老年后很后悔，直到有了孙辈享受天伦之乐才有所弥补。 “

7/18/2026

Today I had planned to write about the relationship between father absence (缺爹) and crime. But something happening right now has disrupted my daily routine and keeps pulling my attention elsewhere. I feel compelled to write about it instead.

It's the poor air quality in New York lately. The smoke is so hazardous that I've been avoiding my usual morning walk outdoors.

Toxic smoke is drifting south from Canada, where more than 800 wildfires are burning, degrading air quality across a vast region and triggering air quality alerts as far south as New York.

One fire in northern Ontario, Canada forced residents from local First Nations to evacuate, with one chief saying that her community has been "burnt to ashes".

We are considered lucky because cities bordering Canada are clouded with a thick blanket of smoke. Non-urgent outdoor events had to be cancelled for fear of inhaling toxic fumes.

A few years ago, people tended to think of Canadian wildfires as occasional regional events. Now, they have become recurring international news because of their scale and the enormous amounts of smoke they produce.

There are probably multiple contributing factors:

• Warmer temperatures lengthen the wildfire season and dry out vegetation, making forests easier to ignite.

• Drier conditions and drought leave trees and underbrush highly combustible.

• Lightning ignites many fires in Canada's remote forests, especially during hot, dry summers.

• Forest conditions also matter. Decades of fire suppression in some regions can allow fuel to accumulate, making fires more intense once they start.

• Human activity—whether accidental or intentional—still causes a portion of wildfires, particularly near populated areas.

Most climate scientists would conclude that climate change is increasing the likelihood of the hot, dry conditions that allow large fires to spread rapidly. This changes the background conditions so that once a fire starts, it is more likely to become large and out of control.

Sadly, when disaster strikes a distant land, its consequences seldom remain local. Smoke freely crosses borders, just as pandemics, pollution, and climate do. We often think of distant disasters as someone else's problem—until they become part of our own daily lives.

Perhaps this is Mother Nature's reminder that, despite the borders we draw on maps, we all breathe the same air. When forests burn hundreds of miles away, we are reminded that we share not only one atmosphere, but also one future.