Via Sully, I see that "Ferris Bueller is a figment of Cameron Frye's imagination" thing is taking off, despite the fact that it makes no sense whatsoever.
It's telling that the write up on Cracked.com has to point out that Sloane is, indeed, a figment of Cameron's imagination too. She has to be, of course; I mean, there she is, talking with Ferris, interacting with him, making out with him! So Sloane isn't real. Of course, if Ferris isn't real, can Ferris's family be real? Probably not, right? So what's the half of the movie that is devoted to his parents and sister about? All of that screen time, the imaginations of Cameron? Does Cameron really sit around his house, imagining Ferris breaking the fourth wall to describe how he fakes being sick to his imaginary mother? That's some serious goddamn psychosis.
Who is the secretary and Principal Rooney talking to on the phone when they are talking to Mrs. Bueller? I'm presuming that Mooney and his secretary are real. Somebody is running that high school. So what's going on? Are these conversations that Rooney is having with Cameron's absentee parents? When the secretary is upbraiding Jeannie, who is she talking to? Who gets arrested for making a phony emergency call to the cops from the imaginary Buellers' imaginary house? (Did Rooney get bitten by an imaginary dog? By Cameron's dog? Would the Frye's really have a dog?)
Does Cameron go to lunch by himself? How does he get into the fancy restaurant without a reservation? Does he pretend to be Abe Froman? If he's pulling the Abe Froman trick, then who is on the other end of the phone call that, in fact, makes the trick possible? When they leave the restaurant, who are they hiding from, if not from Ferris's father? (Are the businessmen sharing a cab with him imaginary too?) Is it Cameron's father? Who the hell is Edward Rooney chasing throughout the Chicago suburbs? Who is drugged up Charlie Sheen hitting on? Whose name is Ben Stein calling out? Is it Cameron Frye's? That would mean that a student is telling him that it was Cameron who supposedly passed out at 31 Flavors last night, right? If so, then why would Ben Stein move on to calling out Frye immediately after that? Or is that interaction, too, all in Cameron's mind? Is there a Ben Stein economics teacher character? Is there a high school?
None of this makes any sense. For it to make a semblance of sense, you've got to imagine that fully ninety-some-odd percent of what appears onscreen is just one of Cameron's many-layered delusions, several of which involve completely quotidian, boring logistics like an imaginary girl having her imaginary boyfriend fake the death of an imaginary (including to the imaginary characters, mind) grandmother. So okay, let's roll with that. My question is why you would bother with the movie at all. If the large majority of interactions involve illusory characters, and we necessarily have to imagine that the presumably real characters are having imaginary interactions with imaginary characters, and we're left with a narrative where almost nothing survives that is real... what the hell is the point?
Some of these theories can indeed be fun, but there's got to be some semblance of internal logic or consistency. Otherwise, the "theory" is as imaginary as, well, this theoretical Cameron Frye's internal world.