“The first question he had been concerned with—a long time now—was why most crimes were so easily discovered and solved, and why nearly every criminal left so clear a trail. He arrived by degrees at a variety of curious conclusions, and, in his opinion, the chief cause lay not so much in the material impossibility of concealing the crime as in the criminal himself; nearly every criminal, at the moment of the crime, was subject to a collapse of will-power and reason, exchanging them for an extraordinary childish heedlessness, and that just at the moment when judgment and caution were most indispensable.”