On the open roads of America, Yifei Xu has conducted an experiment on humanity.

Far from his home in Shanghai, he cycled across the United States for more than four months, enduring rain, rugged terrain, and uncertainty in a foreign land, all to demonstrate what he believes to be a universal truth.

“I want to show that human nature is good!” Xu said.

The 33-year-old relied solely on the kindness of strangers for every meal, addressing ordinary Americans with the same tone: “Hello, I’m a cyclist from China, can you offer me something to eat?”

Xu previously traveled by bicycle through Russia, England and France. And while not all of his encounters in the United States were positive, Xu said the vast majority of the responses he received (in places like Catawissa, Pennsylvania, and Bennington, Nebraska) proved him right, lifting his spirit and keeping him spending endless hours in the path. road and uncomfortable nights sleeping in his tent.

“To be honest, before I came here I had a different, and you could even say, slightly negative, perception of the United States,” Xu said in Mandarin, speaking to NBC News. “But a lot of people here have offered to help me without expecting anything in return and that has really touched me.”

Throughout his trip, Xu shared hours-long meals with dozens of families. And although many people offered him something other than food (maybe cash or transportation), he said he refused both. For Xu, the opportunity to spread goodwill seems to be his only reward.

David Hatker was at home having dinner with his family in Davis, California, when Xu knocked on the door.

“I feel like I got more out of it than he did,” she said. “I offered him a meal; “He gave me a great lesson in the generosity he experienced during this trip.”

With U.S.-China relations at their coldest point in decades, Xu sees his bike ride as an ongoing diplomatic mission, breaking down barriers one meal at a time.

This story first appeared in NBCNews.com. More from NBC News: