Ronald Knox and the Rules of Detection

Ronald Knox, about whom I posted the other day, was a keen Sherlockian, and an intellectual student of the genre. He was involved with the Detection Club right from the outset, and was among the contributors to Club publications such as Behind the Screen and The Floating Admiral.

He is, however, probably best remembered by mystery fans today for his ‘Decalogue of Detective Fiction’, which began life as a lecture and later formed the preface for a volume of short mystery stories which he edited in 1928. He argued that the detective story is a tale told back to front, with the body appearing early in the story and the detective trying to establish the facts which led to the murder. He argues that the formality of the true detective story (as opposed to the thriller, which depends for effect on shock value) required a set of governing rules and he set out his own idea of the ten commandments of the genre.

The first commandment, for instance, is that the ‘criminal must be someone mentioned in the early part of the story, but must not be anyone whose thoughts the reader has been allowed to follow’. Even today, this concept seems to me to have some merit in relation to the whodunit, but like all rules it can be broken to great effect by writers of talent. Some of the other commandments (‘not more than one secret room or passage is allowable’) are a touch facetious while ‘the detective himself must not commit the crime’ is a rule which, if rigidly enforced, would have deprived us of a number of classic crime novels.

So Knox’s commandments are fun, and a historic curiosity, but not much more than that. However, I can’t help wondering - do readers of this blog have any commandments of their own for modern day writers? If so, let me know!