Dalrymple begins:
In my career as a doctor in prison, I met a few swindlers in my time and on the whole I liked them. They had charm and intelligence, which perhaps is unsurprising. It isn’t easy to imagine a charmless swindler, after all; it is almost a sine qua non of the trade. Whether their charm preceded their swindling or they developed it in order to practice their swindling is hard to say, though the former is more likely. Be that as it may, their charm was their stock-in-trade and human gullibility the market in which they sold their wares.