Historedia
Episode 1 of 2

Communication to De Morgan

When
1852
Where
unspecified
Part of
Francis Guthrie conjectures the four color theorem at University College London

Guthrie inquired with his brother Frederick, who then took the question to Augustus De Morgan.

Francis Guthrie inquired with his brother Frederick regarding the coloring problem. Frederick then took the question to Augustus De Morgan. De Morgan recorded the inquiry, noting that Francis Guthrie had posed the question. This communication established the link between Guthrie's observation and the mathematical community's awareness of the problem.

Sources

  1. Four color theorem Wikipedia, revision of 2026-09-20

Machine-drafted from the cited Wikipedia passages and checked by a reviewing model, not by a human editor. Every passage cites the revision it was written from; dates and places follow those passages.