Demonstration in Chinese and Vietnamese mathematics 533
bibliographical chapters of dynastic histories, as Table 15.3 shows), whose
lifetime presumably was not too distant from that of Liu Hui, off er a slightly
narrower range of styles. Th e best-known contribution of Zhao is his jus-
tifi cation of a series of quadratic identities with the help of geometrical
diagrams, to a certain extent similar to those used by Liu Hui in his com-
mentaries on the ninth chapter of the Jiu zhang suan shu. 59
Th e actual intentions that Liu Hui and Zhao Shuang had when writing
their commentaries on the Jiu zhang suan shu and Zhou bi suan jing , respec-
tively, do not seem related to any kind of educational activity. However,
59 Gillon 1977 ; Cullen 1996 : 206–17; CG2004: 695–701.
Number
Th e extant treatises
used in the
Mathematical College
Commentators as
specifi ed in offi cial
histories
Commentator(s) of
the extant treatises
9 Qi gu suan jing
(Computational
treatise on the
continuation of
[traditions] of ancient
[mathematicians])
Li Chunfeng (?)
( Jiu Tang shu ); i^ L i
Chunfeng ( Xin Tang
shu )
Th e author (Wang
Xiaotong )
1 0 Shu shu ji yi
(Records of the
procedures of
numbering left behind
for posterity)
Zhen Luan ( Jiu Tang
shu and Xin Tang shu )
Zhen Luan
a^ Li 1977 : 269–271 quotes these and other sources mentioning the names of
commentators.
b^ Zhen Luan is mentioned as the commentator and the author ( JTS 47: 6b).
c^ Th e title is mentioned as Jiu zhang suan jing ( SS 207: 3b).
d^ Liu Xiaosun of the Sui dynasty (581–618) authored the ‘computations’, cao.
e^ Conventionally identifi ed as Zhao Junqing also known as Zhao Shuang
, the author of the commentary found in the extant edition of the treatise.
f^ Th e Jiu Tang shu mentions three diff erent editions of the treatise, two commented
upon by Zhao Ying and Zhen Luan, and one compiled by Li Chunfeng ( JTS 47: 5b).
g^ Th e Xin Tang shu mentions four diff erent editions commented upon by the three
commentators separately (Li Chunfeng is credited with the authorship of two
commentaries) ( XTS 59: 12b, 13b).
h^ In the Song shi the treatise is mentioned as authored by Wang Xiaotong ( SS 207: 3a).
i^ In the Jiu Tang shu both Wang Xiaotong and Li Chunfeng are mentioned as the
authors ( JTS 47: 6b); probably, the text of the history is corrupted and Li Chunfeng
was originally mentioned as a commentator.
Table 15.3 Continued