Reply to a comment on earlier post

An anonymous reader of my running commentary (or blather?) in this blog has left a comment to my original post on Tana French's In the Woods. I'm reposting his comment and my reply, with a request for further discussion about the character of crime novels and/or mysteries. Here goes:
"Anonymous said...Dont you get it.....Ryan did the original murders and that is why he blocks out what happened....12:12 AM". My reply was "Anonymous thinks that the novel is a puzzle to be solved, and that the answer is Ryan as the murderer in the old case (the murder of his 2 childhood friends). I think the novel is more than a puzzle, and the obvious possibility that Ryan murdered his friends is no more certain (or essential to the novel) than the other possibilities, criminal or metaphysical. 6:52 AM". BTW, I'm not up reading blog comments at 6:52AM, that's California time and I'm on East-Coast U.S. time. But the exchange implies the question of what a crime novel or a mystery is "about," especially in the case of a complex story or a novel with literary aspirations. Is it important to know who murdered Ryan's friends? Some of the reviewers on Amazon thought so--they were disappointed by the novels conclusion. Are the metaphysical overtones that are if anything emphasized by the ambiguous conclusion a problem for a crime novel? And is the solving of a puzzle a necessary distinguishing characteristic between what we are these days calling "crime fiction" and mystery novels? Any thoughts?