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In 1978, two years after Mao Zedong’s death, a reform-minded Chinese official wrote an article in a Communist Party publication. Titled “Practice Is the Sole Criterion for Judging Truth,” it was meant as a subtle critique of Maoist ideology. Mao had prioritized ideology and obedience. The reformers wanted to prioritize empiricism: Whatever worked, China should do.

Deng Xiaoping, who became China’s leader in 1978, was part of the reform crowd and began promoting the empirical approach with a saying: “Seek truth from facts.” Under Deng, China remained authoritarian and could be brutally repressive. But it was also practical — firing incompetent local officials, admitting students to schools based on performance and opening up its economy to investment and competition. It’s no coincidence that China since 1978 has enjoyed one of the most phenomenal economic booms on record.

I thought of this history when reading the heart-rending story of Li Wenliang, the doctor in Wuhan who in late December tried to sound a warning about the coronavirus. Instead of listening to him, Communist Party officials muzzled and criticized him. Li later contracted the virus himself, from one of his patients, and died earlier today. A photo of him wearing an oxygen mask in his hospital bed flooded social media.