The Western science and technology which invaded Chinaduring the mid-nineteenthcentury, in the wake ofEuropean military and economic aggression, entered aculture witha long indigenous tradition of naturalphilosophy, formed by extraordinary figures suchasZhang Heng (78–139),Sun Simiao (581–682),Ge Hong (c. 21–341),Shen Gua (1031–1095)and Song Yingxing (c.1587–1665). Moreover, as modern research has shown,China was, at least until about A.D. 1400,moreadvanced scientifically and technologically thanWestern Europe in many respects. Thesmall minorityof late Qing scholars who showed any interest in thenatural world or intechnology could consolethemselves that they were working within a noble butneglected side-stream of Chinese culture.