 Hasdai, who soon perceived that the letter could not be delivered to the caliph in its present form, persuaded the envoys to send for another letter which should contain no objectionable matter.John of Gorze said that he had "never seen a man of such subtle intellect as the Jew Hasdeu" ("Vita Johannis Gorziensis," ch.cxxi., in G. H. Pertz, "Monumenta Germaniæ", iv.