When I worked in Tian Jin, China, in the seventies, most of the professors were very skinny. Professor Jin, who spoke excellent English, was a veritable skeleton. He was very worried about the high prices of the apartments in China, and interrogated me about the Israeli situation. He was shocked by the prices here, and that was forty years ago when the prices were a quarter of today's. He was worried by the poverty of China, and I told him that the Chinese are so hardworking that in no time China will be a middle class country. I was right. I also told him that the one child policy then imposed was a big mistake, but he said that "We are too many". That inhuman policy was a big mistake, an irreversible big mistake.
Today China is providing incentives for a second child. Currently the Liaoning province has a TFR of 0.9 which is among the lowest and most unsustainable among the peoples of the world. 20.6% or the population are over sixty: this northern population is dying off. The province was formerly known as Manchuria and is among the most industrialized.
Being a Jew, my Chinese hosts were curious why we are so smart. I told them that we underwent the most severe selection in history, expulsions and mass murders, so only the fittest survived and did not abandon their identity. In my case, Jews in Hungary (and Bohemia and Germany) had no permanent residence permits and for hundreds of years they lived as ambulant illegal small salesmen, from one fair to the other, barely tolerated in trades that did no compete with the natives, such as money-changing and unsecured credit. One had to be a genius to survive in those trades. And my parents, among the few survivors of Auschwitz and the forced labor brigades. The Chinese left it at that, but without understanding, because in those post Cultural Revolution, intellectuals were incredibly limited and "provincial", and there was nothing in Chinese recent or imperial history resembling anything like the Jewish experience that they could even remotely compare.
Pic: A propaganda painting "National Harmony" commissioned by the Japanese regime in Manchukuo, with dancing girls of five nationalities Chinese, Manchu, Korean, Mongol and Japanese.