The discovery in 1977 at Fuyang (Anhui province) of several mantic instruments dating from the beginning of Western Han (ca. 165 B.C.E.) marked a decisive change in modern studies of early Chinese science, divination, and religion, many of which now regard the shi 式 as the material basis for modes of thought in Warring States, Qin, and Han culture. While the examples of devices discovered to date have provided a valuable interpretative key to early Chinese schematic cosmography, the meaning of the term shi remains a source of perplexity as its connotations are imprecise and can vary from one author to the next. Whether this change is an accurate representation of ideas about the shi in pre-Han and Han is precisely the issue at stake in the present paper. The following conclusions are drawn: (1) the existence during the Han of several instruments of the shi type no longer permits the use of the term to refer to a singular and unique device, even though evidence drawn from the received texts tends to show the contrary; (2) the multiple meanings of the term shi, as well as the gradual shift between its strict sense as mantic device (shipan 式盤) and its broad sense as calendrical astrology (shizhan 式占) give rise to serious misunderstandings when it is used alone; (3) since these mantic devices are primarily offshoots of pre-Han and early Han astrographic and calendrical theories, the patterns and designs that appear on their surface (shitu 式圖) need to be considered within the larger scope of the spatial representations of calendrical time cycles, of which the excavated texts and artifacts now offer numerous examples; (4) the widespread use of the term shi-method (shifa 式法) in modern studies when referring to some mantic techniques described in the manuscripts raises the interesting question of how to delineate boundaries between the early developments in calendrical astrology and the hemerological practices in general.