"Böhm and Wicksell and Cassel and Wieser and Clark and Walras and Hayek and other economists before and after Sraffa, all must face what the role of intertemporal pricing must be in organizing technologies that are irreducibly time-phasing. When Joan Robinson and I discussed these matters face to face, I used to get nowhere with her by babbling about supply and demand. She already had seen through that tommy-rot. Things went better if I could keep the focus on Mao’s China. "Could Mao’s 1970 China now, sans trade, produce a U.S. per capita standard of living for her near-billion population?" "Of course not. She can’t convert her few steam trains into diesels and electricfed railways. Her workers can use only few and primitive tools. Their medical care is fragmentary, their years of education limited by China’s previous despotism." "Joan, by what steps can a People’s Society move into the golden-rule plenty available to a 1970 America, or Britain or Spain?" "First they should build the higher-yield bridges, roads, and machines. Then, later, deferred and delayed projects can be ranked in their turns." Trite stuff, you will say? That is my point. Learned Aristotle couldn’t handle such trite stuff. And neither could the physicist-statistician P. C. Mahalanobis who had Premier Nehru’s ear in the decades just following India’s liberation from the British Empire."