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Reflections of a working writer and reader



The Sins of Father Knox

Ronald A. Knox (1888-1957) was a British clergyman and detective story writer. In 1929 he issued the following “ten rules” that guided detective fiction in its so-called Golden Age:

1. 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.

2. All supernatural or preternatural agencies are ruled out as a matter of course.

3. Not more than one secret room or passage is allowable.

4. No hitherto undiscovered poisons may be used, nor any appliance which will need a long scientific explanation at the end.

5. No Chinaman must figure in the story.

6. No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.

7. The detective must not himself commit the crime.

8. The detective must not light on any clues which are not instantly produced for the inspection of the reader.

9. The stupid friend of the detective, the Watson, must not conceal any thoughts which pass through his mind; his intelligence must be slightly, but very slightly, below that of the average reader.

10. Twin brothers, and doubles generally, must not appear unless we have been duly prepared for them.

If you are a writer in the 21st century your main task is to break all these rules on a regular basis. Though you may find that someone got there before you.

12 Responses to “The Sins of Father Knox”

  1. Simon says:

    Must read post for all film directors and story writers! Good tips! – Simon

  2. Jim Murdoch says:

    I think Watson would take great offence to being labelled as ‘stupid’ and I’d like to think Holmes would be equally offended on his friend’s behalf.

    jb says: The sins of Father Knox, eh, Jim?

  3. Angeline @ marcus evans scam says:

    These 10 rules were written from a detective’s mind. All these 10 rules interests the reader. I wish the detective writers to write based on these 10 rules.

  4. Bayushi Kaukatsu says:

    I support 1, 4, 8, and 10 wholeheartedly. I think secret passages and magic should be used sparingly. 7 is best when the detective is either obviously the villain or when he’s nuts (see the movie Fight Club or the manga Higurashi no Naku Koro ni: Onisarashi). 9 and 5 are pretty worthless, in my opinion.

  5. Michael Valada says:

    #5 is misinterpreted nowadays, and it references a cultural aspect that is mostly gone from society today, but still has a slight undertone prevailing. It refers to the one person that comes from a significantly different culture, usually speaking with a severe accent, placed into the story only for the sake of being the murderer. At the time Knox wrote these rules, almost every time it happened in a story, it was ALWAYS a Chinaman, but it does not have to be one to violate this trope. Think of it as synonymous to “The Butler did it” and you understand how common this particular offense really was.

  6. Corey says:

    I see someone referencing Higurashi, so I would like to point out the visual novel Umineko no Naku Koro ni by Ryukishi actually talks about these rules directly, and the purpose to them. It was interesting to see how the rules were used in the 5th entry to the series, and how the characters explained them.

    Personally, I think these rules should be ignored to an extent. In real life you can’t be guaranteed knowledge of certain aspects, and as such I think mystery novels should be the same. As a matter of fact, Higurashi has an example of this by showing the story through two point of views, and explaining how the killer changes all on perception.

  7. RJ says:

    His brand of detective writing is still applicable today. However, some of his guidelines may be obsolete. Yet, this so called “Golden Age” is one good era.

  8. maggie says:

    Hi there! Fiction writing should be made apt to the thinking and technology of the 21st century. J.K.Rowling and Stephanie Meyer would oppose number 2.

  9. john baker says:

    Hi Maggie, As I said in the article, if you are a writer in the 21st century your main task is to break all these rules on a regular basis. Though you may find that someone got there before you.

  10. LC says:

    I think these rules can still be used effectively to some extent. The times change and so adaptations must be made. however, I support the essence behind the 10 laws for a mystery. I believe i saw it in the higurashi series, that they referenced the ‘fun’ of reading a mystery, whose goal is to make you try to deduce the culprit, only to find it some undiscovered person ‘X’. that makes a puzzle you have 0 chance to solve it, thus taking the fun of the mystery out. At least that is my opinion. also, no offense to the guy that generalized with fiction, but these rules where made for mystery. I don’t see Harry potter solving a crime =p

  11. Zamora Lanz says:

    Some the the rules that were stated above are still used at this moment. Though, there are some people who take this for granted because they thought that this will not help them to live a healthy and peaceful life. However, every individual has their own certain beliefs which guides and assist them with their daily living. For me, these are the rules that should be remembered and cherished everyday.

  12. Jessica says:

    “No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.”

    That’s hilarious because I can’t remember a mystery movie made since I was born that doesn’t involve intuition or accidental discoveries. Yeah I Know this post is about books, but we’re currently living in the Silver Screen Era 🙂