Sarah Weinman unearths S.S. Van Dine's famous Twenty Rules, rightfully singling out #15 as the one still most important eighty years on - I am more hesitant in respect to her contention that mystery fiction having become "more about the emotional and the visceral" is "rather a good thing". Van Dine's rules for the most part were actually quite reasonable despite the bad press they've been getting for eight decades, and anyone setting to write a real mystery rather than just a mainstream novel with a criminal element should definetely take a look. The main interest of this syllabus, however, is a historical one. Not as an embodiment of Golden Age ideals of good mystery writing, which it clearly isn't: major authors of the era as well as many lesser ones either ignored or deliberately violated its most contentious ukazes. Van Dine himself broke free from his own laws on numerous occasions (Kennel Murder Case, anyone?)
The Twenty Rules are important for just the same reason as Freeman's Art of the Detective Story, Carolyn Wells' Technique of the Mystery Story, Ronald Knox's Decalogue or even - God forbid - Raymond Chandler's Simple Art of Murder. There you have authors from different stripes and backgrounds pausing one moment to think about the genre they practice and giving their own answers to some hard questions - in short, doing theory. What is this thing called mystery and what is it for? Where does it come from and where is it heading to? How does it work and how can it be made to work even better? Is it "serious" fiction, fluffy entertainment or something else? Is it about plot or character, real-life or fantasy? They were not the only ones pondering these issues: Dorothy L. Sayers, Anthony Berkeley, John Dickson Carr, Anthony Boucher, our old friend Julian Symons in the Anglo-Saxon world or Boileau-Narcejac and Jean-Patrick Manchette on this side of the pond also chimed in. Theory was a driving force in twentieth-century mystery writing, leading at times to violent wars such as the one Carr and Chandler fought for years without ever meeting each other. Yes Virginia, they took the genre that seriously back then.
Feuds of that kind are unlikely to happen nowadays. Theory is now mostly confined to fanzines, discussion groups and blogs like the one you're kind enough to pass by; most authors, critics and readers agree on the (very basic) basics of the genre and don't give a damn about the whole thing anyway. It's both fascinating and infuriating to see that many "fans" are more interested in what mystery fiction allows - social comment, psychological studies, political messages - than the genre itself, hence the proud illiteracy met in countless articles and interviews as well as the academism, both formal and thematical, of a large part of contemporary crime fare. Why bother to learn about the history of a genre, or try to make it progress, when to you it's just a convenient medium? Just keep doing what you've always done, and reading what you've always read.
No art form, and mystery fiction is undoubtedly one, can move forward if it doesn't explore, question and try to renew itself. That's why we need theoricians, and most particularly authors-theoricians, more than ever. Will the next Willard Huntington Wright please stand up?