This will only make sense if you've read Calvin & Hobbes as a kid. Basically metaphilm.com analyzes the parallels between the comic and the movie, Fight Club. Is it a stretch? Does it add up? It's for you to decide. I just thought it was an interesting tie-in. Here's an excerpt:
Just as Calvin has an imaginary jungle-animal friend named Hobbes, whom everyone else believes to be nothing but a stuffed toy, "Jack" in Fight Club has an imaginary cool-guy friend named Tyler, whom no one but Jack can see.
In both cases, the entity that began as the ideal companion soon took on a more realistic, three-dimensional quality. In other words, they became real. This is evident in that both Hobbes and Tyler also began to function as scapegoats for their creators. For instance, consider that Calvin often blames broken lamps and other assorted household mischief on Hobbes, and that Jack is inclined to believe that Fight Club and other various anti-society mischief is brought about by Tyler, not himself. Calvin claims Hobbes pounces on him every day after school; Jack believes Tyler beats him up next to 40 kilotons of nitroglycerin in a parking garage—the list goes on and on. The relationships between the two sets of friends are the exact same. Is this mere coincidence?