“The dog was dead. There was a garden fork sticking out of the dog. The points of the fork must have gone all the way through the dog and into the ground because the fork had not fallen over. I decided that the dog was probably killed with the fork because I could not see any other wounds in the dog and I do not think you would stick a garden fork into a dog after it had died for some other reason, like cancer, for example, or a road accident. But I could not be certain about this.” 

The narrator, Christopher Boone, describes his encounter with the murdered dog. His dry, ironic observations bespeak a mind coolly capable of reasoning in the face of grisly tragedy.

“My name is Christopher John Francis Boone. I know all the countries of the world and their capital cities and every prime number up to 7,057.” 

Christopher introduces himself with a sampling of his knowledge; this signals that information and its acquisition are his chief concerns. Knowledge and reasoning define him. His interest in prime numbers reflects in the book’s structure. 

“I like dogs. You always know what a dog is thinking. It has four moods. Happy, sad, cross and concentrating. Also, dogs are faithful and they do not tell lies because they cannot talk.” 

He doesn’t much care for people, but Christopher likes animals, especially dogs and his pet rat, Toby. Animals are simple; they don’t have complicated faces or say complex things that he doesn’t understand. Thus, his autism isn’t an issue for animal friends.