释谭峭的“四镜”

Explanation on Tan Qiao's “Four Mirrors”

南唐道士谭峭在其著《化书》中言及“小人常有四镜”。根据其对此四镜的成像描述，有人认为是四种反射镜，有人提出是四种透镜。该文在分析诸说、考证相关文字和比较考古文物之后，支持透镜说，并对四种透镜类型提出新看法。

In his Hua shu (Book on change), Tan Qiao, a Taoist scholar of the Five Dynasties (907-960), speaks of 'I usually keep four mirrors. M Based on Tan's description of image formation of these four mirrors, some thought them to be four reflectors while others believed them to be four lenses. After an analysis of the various statements coupled with textual research done on correlated writing and excavated archaeological objects, this paper supports the former argument and gives its new views with regard to the type of the four lenses.