The Chinese began printing 600 years before Johannes Gutenberg introduced the technique in Germany. They built the first chain drive 700 years before the Europeans. And they made use of a magnetic compass at least a century before the first reference to it appeared elsewhere. So why, in the middle of the 15th century, did this advanced civilisation suddenly cease its spectacular progress?
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Needham never fully worked out why China’s inventiveness dried up. Other academics have made their own suggestions: the stultifying pursuit of bureaucratic rank in the Middle Kingdom and the absence of a mercantile class to foster competition and self-improvement; the sheer size of China compared with the smaller states of Europe whose fierce rivalries fostered technological competition; its totalitarianism.