Many people know that photography was invented in France in 1839, but the principle behind photography-- that of an image cast through a pinhole-- was known as long ago as 400 BC in China's Warring States period, when it was discovered from natural optical phenomena by Mo Di (c. 468-376 BC), the founder of the Mohist school in Chinese philosophy, and his followers.
許多人都知道，攝影術是西元一八三九年法國人所發明的，然而攝影的原理﹘﹘針孔呈像，卻早在西元前四百年、中國的春秋戰國時代，就已經由墨家創始人墨翟，和他的門徒，從大自然的光學現象中發現，並且記錄在《墨經》中，通稱「墨經光學八條」。