Art forgers have a tendency to present themselves as bohemian rebels, heroically cocking a snook at an immoral art market. Scratch a little deeper, however, and the reality is rather more mundane. Most of them are embittered or failed artists who behave no differently from credit-card fraudsters, except that they use rather more talent to swindle their victims. I met two in my time: Eric Hebborn and Tom Keating. They both struck me as disingenuous types, Hebborn particularly so, a drunk who was happy to wear the mantle of the artistic rebel to disguise an absence of principle.