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Explanation given by Newton to Leibniz in response to the latter's request for details about Newton's newly developed method of fluxions and fluents, in the form of an anagram for «Data æquatione quotcunque fluentes quantitates involvente fluxiones invenire, et vice versa».

Who's not shared the feeling that Leibniz must have felt at getting this response when reading obscure explanations in the literature? :P