Murder at the Margin
EVERY GREAT DETECTIVE has his or her milieu. For Sherlock Holmes it is the dingy streets and stately mansions of Edwardian England. For Miss Marple it is a British country village. For Inspector Maigret it is the boulevards of Paris. Such detectives know not only the geography of these places, they know the institutions and the people as well. They understand how things work in their milieu and how people behave there.
Henry Spearman, the detective-hero of Murder at the Margin, has a different kind of milieu, one not confined to any particular time or space. His milieu is inside the head of the rational man or woman, the person who, if given a choice between two ways of achieving a given objective, always chooses the way that costs less. By understanding how such a person would behave, and on the assumption that all the persons involved are rational in that sense, Spearman solves the mystery.
Our detective is an economist. He is a student of rational, goal-maximizing behavior. He also thinks, talks, and acts like a person for whom rationality is constantly foremost in his mind. Moreover, the author, Marshall Jevons, is also an economist. When Henry Spearman neglects to explain adequately the economic analysis that underlies his thinking, the author does it for him.
Spearman, and the author, bring to bear in the course