Thrust and parry: 1710–1713.

Keill's offensive remarks in his Philosophical Transactions paper of (officially) 1708 were too much for Leibniz's patience. He felt that the time had come to demand redress, and so raised the dispute to the level of international diplomacy by formally protesting, as a Fellow, to the Royal Society against Keill's conduct in a letter of 21 February 1711, in which he demanded that Keill should apologize for his libelous insinuations. Newton himself, Leibniz alleged, had discountenanced such “misplaced zeal of certain persons on behalf of your nation and himself” when Fatio de Duillier had first attacked Leibniz as a plagiarist; Fatio had then collapsed without support and clearly Leibniz expected that Keill would do the same, especially under pressure from the Royal Society, which would be conscious of Leibniz's dignity, distinction, and influence even if Keill himself were not. Leibniz's letter to Hans Sloane, the secretary of the Royal Society, rings with a genuine note of injured innocence; he had, he wrote, never heard “the name calculus of fluxions spoken nor seen with these eyes the symbolism that Mr Newton has employed before they appeared in Wallis's Works.” [ABSTRACT FROM AUTHOR]