“I should regard it as a great misfortune if you were to allow yourself to be deterred by the 'clamors of the Bœotians' from explaining your views of geometry. From what Lambert has said and [Ferdinand Karl] Schweikart orally communicated, it has become clear to me that our geometry is incomplete and stands in need of a correction which is hypothetical and which vanishes wher. the sum of the angles of a plane triangle is equal to 180°. This would be the true geometry and the Euclidean the practical, at least for figures on the earth.”
FO