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The addition of "spy" to Defoe's professions seems a good one, but someone has rushed in to take it out saying (a) it is not mentioned in the main text (it is--"[the] leading Minister and spymaster in the English Government. Harley accepted Defoe's services" --though certainly more could be said) and (b) it is open to debate (it is not).

Does anyone know a repectable source that denies Defoe was a spy? To offer a few that do not doubt it:

Oxford Dictionary of National Biography: "Defoe became one of Harley's agents and an opinion sampler. Over the next three years he extended the possibilities of counter-insurgency, invented practices that survive to the present day, and earned the reputation of master spy"