The Curious Incident of the Dog in the Night-Time | Study Guide

Mark Haddon

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The Curious Incident of the Dog in the Night-Time | Chapters 139–151 | Summary



Chapter 139

Christopher describes why he likes Sherlock Holmes but dislikes the author, Sir Arthur Conan Doyle. He asserts Doyle shouldn't be trusted because he believes in the supernatural, such as when he tried to use a medium to speak with the spirit of his dead son. He likens Doyle's "stupid" belief in the supernatural to the many people who believed in little woodland fairies in the infamous 1917 "Case of the Cottingley Fairies." He concludes, "sometimes people want to be stupid and they do not want to know the truth."

Chapter 149

On Monday Siobhan is alarmed to see the bruise on Christopher's face and questions how it happened. Christopher tells the truth but says he isn't afraid of going home, so Siobhan drops it. After school Christopher searches the house to see if he can find his book, which his father took away during the fight. He searches the house methodically, and although he knows not to "mess around" in his father's room, he decides that if he cleans up afterward, he wouldn't really be "messing." He finds the book in a shirt box in his father's closet on top of a stack of letters addressed to Christopher. Christopher immediately recognizes his mother's handwriting and becomes confused. When his father comes home Christopher omits the book search from his summary of the day. Later he sits in his room and reads the first letter in which his mother describes a new job in a steel factory in London. While she was alive Christopher's mother never worked in a steel factory and never lived in London, so he convinces himself the letter belongs to another Christopher and was mistakenly sent to his address.

Chapter 151

Many things in life are mysteries, Christopher explains, but many "mysteries" can actually be solved by using logic and research. He gives an example of the frog population in his schoolyard pond. The number of frogs fluctuates every year leaving many to marvel at the "mystery" of population explosions or depletions. Christopher lays out the science behind the population rise and fall, proving it's no mystery after all.


Again, this section focuses primarily on the theme of truth, not necessarily the definition of truth as has been the focus of other sections, but how one recognizes truth when faced with multiple explanations. Christopher harshly judges Doyle and followers of the Cottingley fairies for being "stupid" in the face of clear evidence to refute their beliefs; yet when faced with his mother's letters, Christopher wracks his brain for possible explanations that would prevent him from facing the obvious truth: his mother is alive and his father lied to him. In Chapter 139 Christopher explains the theory of Occam's Razor, which states the simplest explanation is likely the truest. While Christopher understands the theory, he doesn't embrace it regarding his mother.

Christopher also establishes a paradox for his reader in his discussion of Doyle. Christopher himself likes Doyle's main character, Sherlock Holmes, but dislikes his author. In the case of The Curious Incident of the Dog in the Night-Time, Christopher has led us to believe he is both the main character and the author. Is the reader supposed to believe that Christopher is Sherlock Holmes, the main character, indifferent and detached? Or is the reader supposed to believe that Christopher is Doyle, creating a plot with a crime and suspects and red herrings, and having a more complicated and flawed personality than his main character?

Christopher also, probably unknowingly, foreshadows his own plot while disparaging Doyle, when he says, "you can't talk to someone who is dead." Christopher theorizes science will one day reveal the truth behind ghosts and then gives an elaborate mathematical explanation for the fluctuating frog population, proving when things seem complicated and unpredictable, they are following simple rules. With his mother's possible return, the truth of Christopher's world is being called into question.

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