A city puzzle becomes abstract mathematics

Seki's death provides an exact date for a body of independent Japanese work in algebra, determinants, elimination and numerical calculation.

Seki developed procedures for systems of equations independently of contemporary European approaches.

His notation and teaching shaped wasan, the mathematical tradition cultivated during the Edo period.

His career demonstrates simultaneous innovation in a society with restricted direct exchange with Europe.

Euler showed that the requested walk was impossible by reducing the city to land regions and connecting bridges.

The four land areas each had an odd number of incident bridges, preventing a trail that used each bridge exactly once.

Euler's publication is a conventional origin point, while continuous-line traditions in Africa and Oceania show other culturally embedded studies of paths and networks.

Richard Price presented Thomas Bayes' posthumous essay on inverse probability to the Society.

The essay considered how observed outcomes could update beliefs about an unknown probability.

The event shows that mathematical authorship and survival often depend on editors, correspondents and institutions.