About Wasan / Timeline
How one book led to the next question.
TThis timeline follows selected works and turning points. Dates identify publications, manuscripts, tablets, or policy changes—not a claim that mathematical practice changed everywhere at once.
- 1299China
Zhu Shijie, Suanxue qimeng
A major Chinese introduction to arithmetic and algebra. Its later circulation in Japan helped shape early Edo study of equations and computational methods.
- 1627Japan
Yoshida Mitsuyoshi, Jinkoki
A remarkably successful vernacular arithmetic book whose many editions carried practical calculation and recreational problems to a broad readership.
- 1641edition
Twelve unanswered problems
An edition of Jinkoki ended with twelve problems but no solutions. This practice of leaving idai helped turn publication into an exchange of challenges.
- 1674book
Seki Takakazu, Hatsubi sanpo
Seki answered the fifteen challenge problems left by Sawaguchi Kazuyuki in Kokon Sanpōki. Solving inherited problems became a platform for new notation and procedures.
- 1685commentary
Takebe Katahiro, Hatsubi sanpo endan genkai
Takebe unpacked terse procedures step by step, showing how commentary could make advanced work teachable and preserve its reasoning.
- 1710compilation milestone
Taisei sankei
The compilation project began in 1683 and culminated around 1710 in the twenty-volume Taisei sankei. The year shown here is a completion milestone, not the discovery date of every result contained in the work.
- 1712book
Seki Takakazu, Katsuyo sanpo
Published after Seki’s death, this work includes results on power sums and circle calculations that became important reference points for later scholars.
- 1722manuscript
Takebe Katahiro, Tetsujutsu sankei
Takebe explored numerical patterns, extrapolation, circle measurement, and the practice of mathematical investigation itself. The preface is dated 1722, while an appendix in the Cabinet Library manuscript is dated 1725; the work should not be compressed into a single undifferentiated date.
- 1822sangaku
Irisawa Shintaro Hiroatsu’s six-sphere chain
A sangaku dedicated at Samukawa Shrine recorded the six-sphere-chain problem. The original tablet is lost; its content survives through later records including the 1832 Kokon Sankan.
- 1832edited collection
Uchida Itsumi, Kokon sankan
Collections and editorial work carried older problems into new contexts and helped preserve a record of practitioners and methods.
- 1872education policy
School policy turns toward Western mathematics
The new national school system adopted Western mathematics. Wasan did not disappear overnight: practitioners, manuscripts, local teaching, and later historical research continued.
A note on dates: publication, completion, copying, and dedication are different events. Where scholarship disagrees, the relevant page states the uncertainty rather than forcing a single date.