Thomas Talhelm is a PhD candidate at the University of Virginia and co-founder of Smart Air, a company that specializes in DIY air filters. He talked with us about his commitment to clean air and the difference between northerners and southerners in China.

Tell us about your first trip to China.

To be honest, I didn’t choose to come to China. I was a Spanish major in college and wanted to study abroad in Spain or South America but the program fees were ridiculous. So I applied to this fellowship program that actually paid people to be research assistants on research projects in other countries. I applied for a project in Chile.

A few weeks later, I got an acceptance letter that said, “Congratulations, you’re going to China!” I’m now convinced that some of the best things in life come when we don’t have complete power to choose what we do.

That first trip showed me how fun and crazy it is to live in China—so many opportunities, so much change. It’s quite different from the boring, stable U.S. suburb I grew up in. In the four years I lived in China, I taught at a Chinese high school, studied ancient Chinese, wrote as a freelance journalist and did psychology research on a Fulbright scholarship.

What projects are you working on now?

I’m actually finishing up my PhD at the University of Virginia but this summer I started publishing my experiments showing that a simple DIY air filter can remove over 90% of PM2.5 in your home. Several people told me not to publish it (“Don’t publish it! Use it to make money!”) but I thought being open about data and methods could actually be consistent with creating a business, so I published it anyway.

In September, my collaborators Gus Tate and Anna Guo helped turn that data into a business called Smart Air. We now host workshops where we teach people how filters work and show them how to make their own DIY filter, which we test on the spot with a particle counter. We also ship units from our website and we just started selling filters from our Taobao store.

What gave you the idea to make a DIY filter?

I had always worn a mask, but the airpocalypse really made me start to worry about the air in my home. After researching filters, I concluded that they really could clean the small particles from the air in your home, but when I went to buy one I was shocked to find the one I wanted cost $1,000!

So I did more research and found that they’re essentially HEPA filters, which aren’t expensive at all. So I built my own and bought a particle counter to make sure it was actually getting the really small particles.

You mentioned a PhD in the works. What are you researching?

I do psychology research showing that China has two very different cultures: north and south. I call it “the rice theory of culture.”

I argue that the cultural differences between north and south exist because the north has grown wheat for thousands of years while the south has grown rice. Rice is a unique crop because it requires irrigation systems, which force farmers to coordinate their water use. It also requires about twice as much labor as wheat, so rice farmers form cooperative labor exchanges. Over time, this functional interdependence has given southern China a culture focused on cooperation and avoiding conflict—what people often think of when they think of East Asian culture.

I’ve tested the theory by giving psychological tests to thousands of people from all over China—tests of personality, individualism and thought style. While I was on the Fulbright, I took my research out of the lab and into everyday life. For example, I went to cafes in northern and southern China and counted how many people were there alone. In Beijing, about 35% of people were alone. In Shanghai and Hong Kong (rice cities), it was closer to 20%.

Tell us more about the differences between northerners and southerners.

I think one of the most surprising things about the rice theory is that it makes predictions which fly in the face of one of the most common theories—that modernized places are more individualistic. Southern China (Shanghai, Guangzhou and Hong Kong) has some of the wealthiest cities in China, yet they’re still highly collectivistic. The great cities of the East (Hong Kong, Singapore, Tokyo, Seoul) demonstrate that modernization can coexist with collectivistic culture.

What do you think is the biggest misunderstanding about China?

Gosh, that’s a big question. My light-hearted answer is I wish people in the U.S. knew that Kung Pao chicken is legitimate Chinese food (but fortune cookies and General Tso’s chicken are not).

My more serious answer is that I think the media narrative of China’s economic rise causes people to vastly overestimate how developed China is. Don’t get me wrong: China has come a crazy long way. I can’t imagine what it was like in the 60s. But if you look at GDP per capita, China is still very poor:

The U.S. and Japan are at about $40,000. China is below $5,000 (even a wealthy city like Shanghai is still at about $12,000, less than half of the U.S. average). Now, you can say that’s a bad thing but I think it also means China is far from being finished. It’s got so much more room to run! Isn’t that exciting?

What is one of your favorite or most memorable China experiences?

One of my all-time favorite stories is when my friend [and Smart Air partner] Gus’s dad came back from using the toilets at a hostel in Tiger Leaping Gorge and said, “Someone put some used toilet paper in the toilet paper bin!”

He thought the little bin by the toilet was to provide toilet paper! In other words, he went fishing through a basket of used toilet paper and then wiped his bottom with the cleanest of the already-used toilet paper. Welcome to China, Dad!

What is your favorite hangout spot in China?

If I’m in Beijing, it’s gotta be Cafe 1901. I love that old church architecture and the high ceilings.

If it’s anywhere in China, I think Dali is amazing. When I went to Yunnan, everyone said I had to go to Lijiang, but I found Lijiang really commercial and crowded. Dali was much more laidback–I ended up staying for a few more days just because I liked it so much.

Transcription by Elaine Yoo.