Calvin and Hobbes/WMG

Calvin eventually grows up to be Edward Norton's character in Fight Club. Hobbes is Tyler Durden.
There are many pages devoted to this theory.
 * A certain Grand Unifying Guess related to this is present under Poison Oak Epileptic Trees, if you care to scar yourself.
 * This WMG has become such Fanon, I'm moving it to the head of the list.
 * And Marla's comment about Having not been umm, F'd like that since Grade school seems to point towards some thing happening between Calvin and Susie.
 * Some of us choose to believe she could have meant it even slightly metaphorically; she did, after all, always look for a moving van at his house.

Calvin grows up to be Calvin O'Keefe from A Wrinkle in Time
Freckles, light hair, and a suspicious ability to believe in things no one else can see. It's obvious.
 * Calvin is NEVER shown to have freckles in the comic. Some other (nameless) classmates are. He doesn't have freckles.
 * Besides, Calvin O'Keefe plays basketball. Calvin only plays Calvinball.
 * And Calvin's family is way too functional (and small) to be the O'Keefes.

Calvin's last name is Klein.
Self explanatory.
 * Considering how much Watterson utterly hates consumerism, this, at least, is very doubtful.

Calvin changes his name, dyes his hair, and moves when he is an adult.
To be exact, he dyes his hair black, moves to Gotham, and becomes Harvey Dent. The split personality is already there.
 * So you're implying that either Calvin or Hobbes becomes a murderous psychopath with OCD when Calvin grows up?

Calvin runs away and joins the circus.
He is adopted by the Grayson family, changes his first name to Dick and takes their last name.

All the characters suffer from a yearly Plot Relevant Age Down
In two separate strips, Calvin makes reference to the current year. In two non-consecutive years, he's six years old. Every year, after summer break, he returns to the same grade with the same classmates. It's possible that this loop has continued for longer than the series lets on, given Calvin's advanced vocabulary.
 * He attended Susie's birthday party once. Once.
 * Would YOU invite him back?
 * If any of the God/RealityWarper theories below are true, then Calvin may be keeping himself that age.

The whole world is suffering from a yearly Groundhog Day Loop.
Occam's Razor, and no one is aging up.

Calvin lives in an Alternate Universe version of Hinamizawa.
Calvin is several decades old, and Hobbes is Hanyuu as a stuffed animal.

Also, the last strip is the moments leading up to Calvin's eventual bad end; the rest of the series is less his focusing on the mystery of his constant death and more his enjoying an eternal childhood. Calvin is, after all, more self-serving than Rika, and Calvin has his True Companions limited to Hobbes and Susie. Why bother trying to figure out the mystery of his horrible death when he can just get it over with and have another year of fun and adventure?

Roz is the one who keeps killing him; hence, his utter fear of her despite her being normal 95% of the time.

Calvin's somewhat right about a parental conspiracy...
In the C&H world; parents age down their kids yearly.

The events of the comic all take place during one or two years of Calvin's life.
The comics simply jump around different parts of this time period constantly. So every Christmas-related strip, for example, takes place at the same time chronologically.
 * This theory explains the final comic. Calvin's birthday was the next day. The comic ended because he turned seven.
 * Calvin O'Keefe has come unstuck in time.
 * Im-freakin'-possible Calvin has had a first day of school many times each time different events transpire.
 * This has been my own personal canon for years.
 * This strip obviously invokes the summer vacation strip that got released year before as "last year". I wonder if this proves the guess wrong.

Hobbes is real and exactly what Calvin sees him as
He hides and replaces himself with a stuffed copy so adults don't deduce his existence and freak out.

Hobbes is Tigger.
Tiger? Check. Sentient and friendly? Check. Stuffed with lovable fluff? Check. Calvin's just a conduit for the Hundred-Acre Wood.
 * I'm starting to think Calvin's dad is Chrisopher Robin, in fact...
 * This WMG is TV Tropes Made of Win Archive.
 * Norwegian author Tor Åge Bringsværd, who wrote an introduction to the Norwegian translation of The Essential Calvin and Hobbes, claims that Hobbes is, in fact, Tigger's son. Who has inherited his father's hyperactive nature and fondness for pouncing on his friends, but is more reflective and philosophical.

Calvin is a god in training.
He animated his stuffed tiger; he has created many, many realities; he even erased his "uncle" Max from existence. No sensible person would allow a being with all this power to do anything without learning how to control the power first, would they? Therefore, Calvin's (unnamed) town must be a training ground for him to learn to control his powers so that when the time comes, Calvin alone will be able to decide who lives and who dies. Considering that the one time Calvin imagined that he was a god, he demanded human sacrifices and smote those who disobeyed him, he has a long way to go.
 * This opens up the possibility that Calvin was not the only god-in-training in his neighborhood. We only ever saw Calvin reshaping reality, but that doesn't necessarily mean the other children in the neighborhood didn't. Or, in another universe, another version of Calvin serves as a supporting character to another god-in-training. This, combined with certain similarities between the two characters, suggests that Susie Derkins eventually grows up to become Haruhi Suzumiya.
 * Alternatively, Calvin is Kyon.
 * But the strip takes place in America, probably in Ohio. Haruhi and Kyon are from the Kansai region of Japan. This would explain the fact that they don't have the accents they should. It isn't beyond the realm of possibility that both Calvin and Suzie are Asian in heritage, given the simple art of the strip. Haruhi is in fourth grade or so when she attends the fateful baseball game, and three years is plenty of time to move to Japan. And neither series follows reality in the strictest sense.
 * If Hobbes is reincarnated as the talking cat Shamisen, then this theory becomes even more scarily believable.
 * OR Calvin ISN'T Kyon, and Haruhi merely warped into the C&H universe, turning herself into Susie. She acts the way she does as Susie because her genre-saviness tells her that when he gets older, Calvin will be attracted to her, she'll then rope him in and have another reality warper to play with.
 * You guys are blinded by gender. Haruhi is the imaginative one, and Kyon the sensible one. therefore Suzie = Kyon, and Calvin = Haruhi.
 * Calvin is actually explicitly identified as white. "You rate especially low among tigers and six year old white males." in one of his polls to Dad. So unless Calvin is biracial and somehow looks Asian yet identifies with his European-descended side, I don't see how it would work.
 * The problem with this is that Haruhi is insane, while Susie is much more mature than Calvin.
 * We DO see Susie reshape reality in the strips where she plays house with Calvin. We know it's not Calvin doing it, because he protests endlessly. She may be better at it then he is, considering how much better the art gets when she does it.
 * Not better art than Calvin's dinosaur fantasies. So, dinosaur attacks: The way of the future?
 * As Calvin himself once pointed out, it WOULD keep the human population in check...as would people-hunting deer.
 * The Noodle Incident is where Calvin caused the birth of another god, namely the Flying Spaghetti Monster.

Mr. Bun is the only real character.
In case you've forgotten, Mr. Bun appears only once or twice in the entire run of the comic; he's Susie Derkin's stuffed rabbit. Unlike Hobbes, Mr. Bun shows no sign, within the comic, of ever being "real." ("Mr. Bun seems comatose," comments Hobbes, after attending a tea party with Susie and Mr. Bun.) Naturally, this is strong evidence that Mr. Bun is the only "real" character, and everything else is occurring in Mr. Bun's imagination. If Mr. Bun doesn't actively participate in his expansive fantasy world, it's only because he prefers to just sit back and admire his work.

Mr. Bun is Roosevelt.
Coinciding with the directly above theory, Mr. Bun is how Roosevelt personifies himself in his own imaginary world; similarities: he has the appearance of a stuffed toy, he never moves, and the main characters know literally nothing about him. He projects his own ideologies (admittedly, in dumbed-down versions) of "everyone is either a loser, a fool or a corpse, except me" onto Calvin. In doing this, he is fantasising about how he thinks he would behave if he were a human child. Calvin's rants about consumerism and the stupidity of people are Roosevelt projecting onto Calvin.

Calvin is Frazz.
You look at that hair and tell me they aren't the same person.
 * It all makes sense. Calvin has picked up his dad's love of cycling, and he works at his school so he can maintain some connection to his youth.
 * Also, Frazz's girlfriend is clearly Susie. Obviously, things picked up for him after first grade, and now he plays Hobbes to Holden.
 * Frazz's personality is in some ways an amalgam of Calvin's (fun-loving anarchist) and Hobbes's (wise laid-back observer). Depending on your view of Hobbes, either Hobbes' viewpoint rubbed off on Calvin, or Hobbes was an aspect of Calvin's psyche which was later reintegrated as he grew up.
 * We know that Mrs. Olsen was Frazz's teacher when he was in school; Miss Wormwood could have been younger than she looked, married and become Mrs. Olsen.
 * Or maybe Mrs. Olsen was one of Calvin's other teachers
 * Frazz's name is given as Edwin Frasier, but it could actually be Calvin Edwin Frasier; he uses his middle name to distance himself from his childhood exploits.
 * That, or he changed it when he first tried to break into songwriting and just stuck with it.
 * One problem: a Sunday strip implies that Frazz grew up on a farm (Holden wishes we could go back to an agrarian society for longer summer breaks. Frazz starts giggling and his girlfriend basically says he spent his summers "bailing hay"). Calvin's parents live in the suburbs and never go into the country much less own a farm... unless they move there after the strip ended. Ooh, that gives me an idea!
 * Also, Fazzverse seems to have the same sort of Groundhog Day Loop as Calvin and Hobbes. Furthermore, if Ms. Olsen/Ms. Wormwood was Frazz/Calvin's teacher, then the school is the same, therefore the school is what prevents kids from growing ups, and so Calvin only satrts to age when his parents move to the farm. It all makes sense!
 * After I saw this strip, I decided that this is definitely the case. I mean, sledding?
 * This one seems to indicate that SOMEONE on that sled has had past experiences with busting up a sled or two.

Calvin (age 6) moves to the country and becomes the Boy (~10) from Cow And Boy
...then moves back to the suburbs and becomes Jeremy (15-16) or Jeremy's brother (15-19), and finally Frazz (20s). If he makes purely selfish decisions in life he becomes Slick and never grows physically/mentally/emotionally, although I think he's trying to get better emotionally at least. Hobbes is replaced by Cow because he got lost during the move, which Calvin/Boy rationalizes as Hobbes going feral.

Calvin is Jeremy Duncan from the comic strip Zits.
Hey, kids change a lot between ages six and fifteen... (Apparently, they stop being funny.)
 * Jeremy Duncan has a brother who's a few years older than him (he doesn't appear often in Zits, because he's attending college). Calvin is quite obviously an only child. So how does Jeremy's brother fit into this theory?
 * Alternately, Calvin grows up to be Jeremy Duncan, who grows up to be Frazz. The logical continuation of this is, of course, that Frazz then grows up to be Edward Norton's character from Fight Club. Thus, all four of these characters are gods.
 * Let's go one more step. Calvin grows up to be Jeremy, who grows up to be Frazz, who grows up to be "Tyler Durden," while Suzie grows up to be Haruhi Suzumiya; since Kyon becomes The Doctor, this leads to the inescapable conclusion that after the end of Fight Club, Calvin becomes Captain Jack. What this means for Suzie...bad end. Then again, she's a god. She'll be all right.
 * This also means that Captain Jack is a god...
 * Staying with Jeremy Duncan, it's obvious when you compare each character's parents: Calvin/Jeremy's dad just gained weight in the intervening years. That also means that it's also entirely possible that Susie is Sara and Moe is Hector.
 * Their mothers don't really look the same. Maybe Calvin's/ Jeremy's birth mother died or got a divorce, and Chad is his stepbrother.
 * Jeremy's mom had straight hair in the beginning of the strip, then got the perm she has today.
 * Or, if Calvin's a god in training (see above), he remade Hobbes into his brother and changed his mother's appearance.
 * Hector's the smart one, not the outsmarted. One of the bullies in Zits looks like an aged-up Moe, and Hector could easily have moved there after the events of Calvin and Hobbes ended.
 * No, Calvin is Jeremy's Aloof Older Brother who happens to look exactly like Jeremy but taller and with facial hair.

Calvin is a closeted furry, and Hobbes is his fursona.
Many furries will tell you that, even before they knew what a furry was, they had furry-esque traits as kids (such as an obsession with stuffed animals or exclusively animal-themed imaginary friends). Calvin definitely shows some of those traits in the form of his pal Hobbes. There are also his repeated fantasies of being a dinosaur. There's also the Story Arc where Calvin tests out what life would be like as a tiger like Hobbes, including dressing up in a costume (fursuiting); it supposedly turned out badly, but it could also be interpreted as Calvin's insecurities about "coming out" with his furriness overwhelming his furry pride. That also means Suzie is Mr. Bun, but that gets weird.
 * Bill Watterson is spinning in his grave, and he's not even dead!
 * That is a very insensitive anti-fandom-prejudice-fueled remark, my friend. This one was a nice WMG in itself.
 * It's a bit inconclusive. Calvin's love of stuffed animals and his rich fantasy life are standard gear for any imaginative youngster, and most people who are similar to Calvin as kids don't grow up to be furries.
 * Maybe so, but most kids like to alternate between animal and human fantasy pals. Calvin sticks almost exclusively to animal ones, and there's his repeated declarations that Humans Are Bastards - along with his social ineptitude with other kids. Couple this with Hobbes's barely-contained pride in not being human, and...
 * What about Spaceman Spiff, Stupendous man and Tracer Bullet? Between them they probably outnumber animal based imaginings.
 * ...and you maintain the strip's focus on Calvin and Hobbes, and you keep the cast nicely manageable. Honestly, does anyone out there really think Bill Watterson was writing about furries the whole time? I bet he barely knows what a furry is.
 * Thanks to Rule 34, I'm sure he's far too aware of what a furry is, now.
 * Incidentally, I find it hilarious how practically all of the above tropers subscribe to the "furry = furvert" stereotype.
 * Indeed. Most real life furs don't start out in the fandom as furverts (and, in fact, got their "furry interest" from mundane things like a stuffed animal collection or Funny Animal children's cartoons, hence why a lot of furry Fan Art and Fanfic are about shows like Swat Kats or Sonic the Hedgehog), and Calvin's experiences perfectly illustrate the initial "transition phase" furs engage in, when they discover the fandom (plus, he's still too young to lean toward furversion, though there's no guarantee that he won't become one, as he grows older). Most likely, he's at that transition phase, only just discovering his place in the fandom and exploring it, but still unsure if it's the right thing for him. Hobbes, by extension, was his "gateway drug", going from imaginary friend to conduit of his furry interest and expression.
 * So are we all subscribing to "furry = otherkin", then? I'm a little confused.
 * Otherkin != furry. Yes, you are confused. Just like 'normal' people don't all like the same things, not all furries are the same. The loud weirdos get all the press; just like not all christians are loudmouthed bigoted idiots like Pat Robertson, not all furries wear costumes 24x7, carry modified stuffed animals with genitalia (yet ANOTHER different fandom) and hump legs at a moment's notice.
 * I have to say: I think this may constitute jossing.
 * Not really. Being furry doesn't have to be sexual in nature. He may simply like it as a world basis. He does, after all, enjoy changing into animals and his favorite stories involve tigers, wolves, bears, and hamsters.

Calvin's parents eventually got fed up with him and sent him to a Japanese orphanage shortly after World War 3.
Eventually, he changed his name and dyed his hair, internalized the Hobbes persona, and made friends with another orphan boy named Kaneda.
 * Possibly, his parents were killed, or couldn't support having a child in the post-war climate.

After a few more years of this, Calvin's parents decide to do something about Hobbes.
With tragic consequences
 * You're a monster and you're going straight to hell.
 * Whatever happened wouldn't be pretty. Hobbes is his only real control factor.
 * Check out this skit from Robot Chicken.

Calvin is a Reality Warper.
The justification for this is basically the same as for him being a god, but the results are slightly less fantastic.
 * More like Master of Illusion, only that he can currently do the stuff only on himself, and he doesn't even realize he can do that. Once he grows up a bit, he'll understand the power he holds, learn to affect other people with his illusions, realize that Hobbes is only the projection of his imagination (this'll be hard for him), and possibly make an alignment shift from Chaotic Neutral to Chaotic Good and start to fight crime.
 * Without Hobbes? Chaotic Evil. On the other hand, Hobbes may be an advanced alien, sent to keep Calvin from growing powerful enough to destroy the universe. Calvin would do it, too.
 * Calvin is smart and strong enough to get through the loss fairly easily. Like every other imaginary friend, Hobbes is a projection of certain dormant characteristics; with him gone, Calvin will become more rational and think ahead, absorbing all the qualities of his late friend. Instead of randomly and destructively using his powers, he will give serious thought to the responsibility they bring. He has shown several good qualities during the comic, and probably won't be able to make the final leap to darkness. At worst, he will use the powers for his own gain.

Hobbes is an alien, a Fuzzy Tiger, who transforms into a plush toy when seen by humans
Combine the above theory with the aliens from the episode "Blink" of Doctor Who. Clearly Hobbes' home planet is twinned with the home planet of the Weeping Angels. He can move when Calvin is looking at him because it's only triggered by non-timelord races. He can move in Calvin's eyes even when someone else is watching him for the same reason that the Weeping Angels couldn't move when nobody could see them but the lights were on.
 * Like Kerberos from Cardcaptor Sakura? Spiffy. Perhaps he's training Calvin for a similar mission! Gotta Catch Them All!

Calvin grows up (or rather, doesn't grow up) and becomes Slick from Sinfest
They share at least the same phenotype, so it wouldn't be impossible. Maybe arrogance and self-centeredness is the cause of Calvin's overdeveloped vocabulary...
 * Unlikely, as no one else from the cast have Sinfest counterparts.
 * They don't have to. Hobbes was probably discarded at some time. Slick's parents are never shown. And Calvin could simply have left town and changed names somewhen for some reason. (We don't even know how old Slick is, BTW). Also, WMG is not Serious Business. ;)
 * Ahem...

Hobbes is the same species as the toys from Toy Story, but more powerful.

 * The only one who sees through The Masquerade is Calvin (which has interesting implications for him). But while most toys have to drop in place and "play dead" to maintain The Masquerade, Hobbes is so powerful that he can basically do what he wants, and no one but Calvin will see. Even cameras can't catch him in the act of movement. He exercises the power unconsciously.
 * So, Calvin is a reality warper who is only restrained by Hobbes, and Hobbes is a powerful being whose only check is Calvin. Uh-oh...
 * Here are the living toy levels:
 * Level one: The Christmas Toy: the toy must go back to its original position or else be frozen forever.
 * Level two: Toy Story, The Brave Little Toaster: the toy can change from playing dead to alive at will and have limited communications with animals. They must play dead to hide from humans, other sapient races (Like Mechanical Lifeforms and Funny Animals) level three and four toys and companion animals.
 * Level three: Hobbes: Can only be seen by select members of sapient races. Otherwise seen as a toy.
 * Level four: Winnie the Pooh, Cars: Is always seen as alive, but people know the being is a toy.
 * Level Five: The Velveteen Rabbit: Actually is alive, no longer even looks like a toy.
 * This should be a trope.
 * Indeed it should. Go ahead and start a page with one of those "sliding scale" names.
 * I'm on it.

Bill Watterson is planning to kill you...
...for obsessively theorizing on the nature of Hobbes.
 * Or, more likely, he'll have Hobbes do it.
 * Or it's because you haven't bought one of the 150 different books republishing the strips and read the Uncle Max storyline. He gets on a PLANE, people! A plane! And (example not completed - no carrier)
 * Or for suggesting that Calvin will grow up to be a character in a work far inferior to Calvin and Hobbes.

Hobbes is in fact Calvin's brother

 * Literary Agent Hypothesis states that the events you see happened but have creative licence applied to them. So, one day Calvin's family agrees to have Watterson write comic strips of Calvin during his childhood. Somehow Watterson thinks it's a hilarious idea to portray Calvin's brother as a stuffed animal. Later, he gives up, and another artist (that is, the guy who does Zits) comes along and says he can write strips of Calvin as a teenager. This time he keeps Calvin's brother a human, but to avoid stepping on Watterson's toes, he gives the characters different names. This means that Hobbes was never a stuffed animal, but Watterson got a kick out of portraying him as one.

Hobbes is a Shinigami

 * His tuna addiction is similar to Ryuk's addiction to apples. Calvin has a Death Note, but can't use it because he doesn't want to make an Eye Deal until he knows how much life he has left himself, a fact Hobbes refuses to share. He keeps Suzie alive because he needs her to do something - he just hasn't figured out what. People only see Hobbes as a a stuffed tiger because he chose to possess a stuffed tiger. He can come out of the stuffed tiger at any time to show his true form; while he's inside the stuffed tiger, he looks like a real anthropomorphic tiger.

When Calvin grows up, he'll become a Kira. His alter ego, Tracer Bullet, will be the alias of T from Wammy's house.

Hobbes is a Pooka

 * "Pooka: From old Celtic mythology. A fairy spirit in animal form. Always very large. The pooka appears here and there, now and then, to this one and that one at his own caprice. A benign but mischievous creature. Very fond of rum-pots, crackpots, and how are you, Mr. Wilson?" (Harvey)

Hobbes is in animal form, very large, and appears here and there, now and then, to Calvin at Calvin's caprice. Hobbes is benign but mischievous. He may have been drawn to Calvin, who is already Mittyesque and may be a crackpot in the making.


 * Sir or madam, congratulations for coming up with the first Epilectic Tree I've seen so far on this page (virtually the first one I've seen anywhere on this site) to make a great deal of sense and make me wish I'd thought of it first. The only problem is that pookas in Celtic mythology were not exactly like they were depicted in Harvey, but the Harvey-verse version of pookas certainly does seem to qualify.

Calvin tricked Uncle Max into saying Candle Jack.

 * That's why after he ge

Galaxoid and Nebular are early Daleks.
Nebular the navigator clearly has a rather bloated ego about his "amazing navigation skills"; it's more than likely that he is so bad at it that the two managed to travel, by accident and completely without noticing, several millions of years forward in time. After the appearances they had in the strip, they will return to their own time, and after they die, Daleks will have their usual evolution with the nuclear war and Davros and stuff we all know.
 * In addition, they eventually discover an ancient contract that shows that they have bought planet Earth at a bargain price. But when they come back to check out their new place, they find that Calvin, who never really owned Earth, didn't have the authority to make the trade, which made the contract moot. They'll be ultra-pissed and try to kill everyone; then Calvin will spontaneously manifest his Time Lord abilities and stop them.

Calvin is a Changeling
Likely a Nocker, from his caustic personality and constant inventing. Hobbes is his Chimera companion. His parents are too Banal to see him.

Uncle Max was/is in jail for real
Calvin's dad had not heard from him in ages because Max landed himself in jail for a few years. For whatever reason, Calvin's parents did not want him to know, so his mother tells him it's a stupid idea, but dad ends up hinting it. Max never showed up again because he committed another crime and landed himself in jail again.
 * That suggestion coupled with the fact that I watch a lot of Law & Order makes me a little sick. An Uncle, visits his six-year old nephew once, goes to prison, and is never mentioned again. What kind of crime gets you THAT sort of treatment? Hint: It has it's own L&O spin-off.

Calvin is Lan from Mega Man Battle Network
Hobbes is Calvin's dead twin brother's soul possessing a tiger doll. When Calvin/Lan get a PET, Hub/Hobbes' soul transfers itself to the PET and becomes Megaman. Susie is Mayl.
 * Also, if the 'Calvin is a reality warper' theory is applied, Calvin changes the world to be vastly different, probably stemming from an interest in the internet and Japan as he grows older.

Calvin and Hobbes are either Zim and Gir (set to 100% duty mode) or Keroro and Kururu
Self explanatory.

Uncle Max is Grandpa Max.
That would make Calvin Ben's and Gwen's second cousin.
 * Dude... that is possibly the most awesome WMG on this page. Totally seconded.
 * ...Except that they look nothing alike, unless Max really let himself go.

Calvin is dead.
"Let's go exploring!" Soon after, the sled crashes for the final time. Calvin's obscene luck regarding said crashes runs out.
 * Congratulations, you've written the single most depressing WMG ever.
 * I cried.
 * By the way, this was used as a one-off gag in Lio. (Lio is like that--the day of this writing, it had SpongeBob SquarePants cut in half.)

The MOST depressing WMG ever? I can top that!

 * Calvin Shinji Ikari trapped in an endless Groundhog Day Loop of the End Of Evagelion and is hallucinating Calvin and Hobbes as an idealized childhood against his will so that an Elder God can make his soul innocent enough to be eaten in the next cycle. And so on and so forth forever.
 * Too confusing to be depressing.

TOO confusing? I can top that!

 * Calvin is really a gender-bent clone of Thousand-Shinji!Rei, who was sent by Future!Lelouch to assasinate Gandalf and* CLONK* 
 * We apologize for the inconvinance. The crazy troper has been subdued.
 * * CLONK*  We wish to inform you that those responsible for clonking the crazy troper have, themselves, been clonked.

Hobbes is an Imaginary Friend
Calvin subconsciously gave him the ability to appear like normal plush toy to others (alternately, he's a plush toy turned into an imaginary friend). Quite possibly his powerful imagination gives him abilities beyond ordinary kids, similar to Mac and Goo.

Calvin is insane.
He's currently in a mental hospital and everything in the comic is just a giant hallucination. All his imaginations are 'real', mainly because nothing is real. Or, maybe he continually switches between reality and hallucinations. So, Hobbes and Spaceman Spiff and all those other things aren't his imagination, he actually perceives them as real.
 * Mars is amazing… Mars is amazing…

Aliens killed Calvin at the end.
To refresh your memory, Calvin and Hobbes ended on New Year's Eve 1995, and a week or two before, there was a Story Arc in which aliens were angry with Calvin for not telling them that Earth is tilted on its axis and has a cold winter every year. The Wild Mass Guess here is that they killed Calvin for his treachery. Hence that's the reason why the strip ended. There are a couple of weeks' worth of strips featuring Calvin and Hobbes appeasing them and then living their normal lives as if nothing happened. But those strips are an illusion created by the aliens, for the benefit of us the real-world readers. They made that illusion simply because they know that the strip's fans wouldn't have enjoyed this kind of Downer Ending.

Calvin has no idea how any of this works.
Simple, really; Calvin is the only normal person living in a world without the rules of reality. To everyone else, turning into a tiger or growing so big you fall off the Earth is nothing out-of-the-ordinary; Calvin is just too simple-minded to see that the fantastic and the everyday are one and the same.
 * What, you're saying Calvin is Plastic Man?

Calvin is an Awakened Mage, and Hobbes is his Avatar.
Calvin is in fact a recently-Awakened OWoD Mage, with Hobbes as his manifested Avatar. All the silly escapades he has are due to his own growing knowledge of the Spheres; Initially, while he only can visit the Umbra in his Avatar form of Spaceman Spiff, he eventually gains the power to visit Umbra Mars physically. Also, his time in the (seemingly-endless) woods, where he is * always* accompanied by Hobbes, are actually Seekings, as his Avatar guides him toward enlightment.

This also explains why Hobbes can physically harm him; It's his way of viewing the Paradox effect, which occurs when he tries something that's seen by too many Sleepers...Also explaining why Hobbes goes dormant in the presence of others. Going by this, Calvin currently has proficiency in the Time, Entropy and Spirit spheres- Which isn't impossible for a beginning Mage.

Alternatively, he might be going Marauder.
 * It doesn't fit quite as well, but his inventions almost fit the Genius mould, and he has a few Mad Scientist tendencies. Perhaps we're looking at a cross-breed?
 * Genius: The Transgression says that occasionally recently catalyzed Geinuses are mistaken for newly-awakened Mages.

Calvin is a Genius, and Hobbes is one of his Wonders.
...Hence the reason Calvin has never used any of his "Inventions" on anyone other than himself: doing so would risk Havoc. It's most likely Calvin was given a crash-course in Havoc and Mania, as well as being directed to the Axioms by a member of the Peerage shortly after "The Noodle Incident", (I.E. his breakthrough).

His wonders include:
 * Transmogrifier, and the Transmogrifier Gun
 * Flaw: transformations being "Invisible to Normals" as well as suffering "Shapeshifter Mode Lock" due to improper construction
 * Duplicator
 * Rank-4 Automata Factory, intigrated into Transmogrifier.
 * Flaw: Manes created always have a lower Morality than the user, with Calvin ranking about Obligation-6.
 * Duplicator V2 (creates "Good" Calvin)
 * Rank-4 Automata, With Rank-5 "Goodness" wonder.
 * Flaw: The Manes evaporate if they even think of commiting an evil act, and are not completely loyal.
 * Time Machine
 * Rank-5 Skafoi with "Fragile" variableintigrated with Transmogrifier..
 * Flaw: Has a 1/10 chance of reversing the direction of the intended time travel.
 * Hobbes
 * Rank-4 Automata, with the "Durible", "Concealed", and "Biological" variables
 * Flaw: Disdaneful of (yet still mostly loyal to) master, and is willing to hurt him in various petty ways.

A couple more things: Calvin's mom could be a Beholden, but it's also quite possible that she was just Lucky that she never caused Havoc. Calvin's dad may or may not be on the verge of becoming a Clockstopper, which would make an interesting Deus Angst Machina for a campaign or fanfiction...
 * Calvin's father doesn't strike me as the type, he's got a creative imagination and an artistic bent. If you combine one or more of the above theories, one or both of his parents may be Geniuses as well!
 * The source book says that Geinuses ocassionay turn up in Occult and/or anti-technology groups, so why can't a Clockstopper manifest wile working as a patent attourney? But you still have a good point: it could be that Calvin's dad is a retired Geinus, and dislikes modern technology more beacuse it reminds him of the life as a Geinus he left behind.

Calvin was Dead to Begin With when the strip started.
And Hobbes is the animal-spirit appointed to guide him through the afterlife. All of his imagined battles as Spaceman Spiff, Stupendous Man, and so on(as well as his "real-world" showdowns with babysitters and "slimy girls") are really against his inner demons, representing his sins in life. In the last strip, when he sledded off into a glaring white snowfield, he was at last moving toward the light of Heaven.
 * Thus, the ending is indeed a Crowning Moment of Heartwarming.

Calvin killed another kid.
In one of the early C&H strips, Calvin mentioned to his mom that a bully (named Tommy or something) had been picking on him, but that the situation was taken care of because "Hobbes ate him". Calvin would have likely buried the body somewhere, to help the illusion of Hobbes' devouring the body, and disposed any other incriminating evidence. Apparently this bully was quite the bad seed, considering Moe has picked on him for years and still lives.
 * Or maybe Hobbes actually did eat the bully.
 * Calvin actually did try to feed Moe to Hobbes at one point. The only reason Moe didn't meet the same fate as that other bully is because he thought a teacher was watching and decided to stop picking on Calvin. Next time he won't be so lucky....

the last strip took place shortly after Calvin killed his parents
Hobbes : "Everything FAMILIAR has disappeared Calvin : "A fresh clean start"
 * Shortly after that, he got lost in the forest and starved to death, since there was nobody to look for him.
 * especially frightening when you consider that before the final strip, Calvin made a Snowman with an ice-cream-scoop in his back and tells Hobbes "It's a sordid story." and the last time we see his parents, Mom was scolding at his Dad to "Shut the door"

In Calvinverse, people lose their imagination powers, and the memories of them, when whey grow up.
That's why they can't believe Calvin, and other kids, like Susie, can make imagination real as well.

Hobbes knows others can't see him
He doesn't tell calvin becuase he would believe him. IN one strip, Hobbes is animated when susie is close by. His face is almost one of terror, and he quickly hands calvin a rotten aple before de-animating. He can move and talk while de-animated, but only calvin can see him and this is hard for him to do, so he generally de-animates when others are around.
 * When calvin grows up, he will stay animated and reveal himself (and others of his kind) to the world.

Calvin's mother made Hobbes.
We've seem Calvin's mother sewing in the strip, so it wouldn't be a stretch to assume she created him as well, when Calvin was only a baby. She also mends Hobbes himself when their adventures get a little TOO rough and tumble. If you believe the theories above...

Calvin's mother is also a God.
If it's true she made Hobbes, the animate inanimate object, what's to say she isn't incredibly powerful as well? At one point in the strip, she tells Calvin "I hope you someday have a kid exactly like you," to which Calvin responds "Grandma says she used to say that to you." This tells us they were similar as children, both intelligent gods frustrated by those around them not being on their level. She just can't tell Calvin that they're the last of a line of gods, because he'd tell everyone. Also, it explains WHY she had a baby instead of getting a dog, and why she is the stay-at-home parent. In addition, Calvin's Mom is the only person in Calvin's fantasies to appear as themselves, and not a monster, thug, or in Tracer Bullet's case, client.
 * Wrong. Calvin's mom very frequently is shown as a monster. But that just disproves one part of the theory.
 * As if to add on the the theory, there are at least two occasions where Mom ends up communicating with Hobbes. One during the raccoon arc, where she laments on the poor animal's fate to the tiger (before catching herself), and again during the Yukon arc, where while searching for Hobbes in the woods, she calls out his name (and causes Dad to question her sanity). Even if they aren't gods, Calvin most definitely inherited his...peculiarities from her!

Bill Watterson is dead.
That's the real reason we'll never see any more comic strips and why no one's put a stop to any bootleg merchandise. Obviously, the introduction to the complete collection was either written in advance or faked.

Hobbes's dual nature is best explained by quantum physics
Come on, a real-and-not-real-at-the-same-time feline? Hobbes is clearly a cousin of Schrodinger's Cat. (Theory stolen from an actual scientific magazine.)

Hobbes is a ghost
Hobbes's is the ghost of Calvin's twin brother, who died before birth, and manifests through Calvin's stuffed animal. This is why only Calvin can see and hear him, as Hobbes only manifests for his twin brother.

Calvin is a Vampire.
And Hobbes is a Weretiger.

...just to round out the New World of Darkness theories.

Calvin is either a Changeling, a Geist, a Promethian, or a Hunter.
What?
 * No, technically Calvin is a Sin-Eater. It's Hobbes who's the Geist, with the stuffed toy as the Keystone Memento. Calvin probably has the Forgotten Threshold as the result of his very first toboggan ride on his own.

Calvin's mum really does put on knee-high boots and a patriotic leotard...
...and may or may not fight crime.
 * Actually, she may in fact be a super heroine/costumed vigilante after all! And knowing that her son will one day inherit her powers, or at least, she wants to push him in the crime fighter direction, she sewed a super hero costume for him allowing him to take on the alter ego of...STUPENDOUS MAN!
 * The powers are related to some sort of variable gene, like in X-Men. Calvin's powers are related to genius and the ability to warp reality with his imagination within limitations (for instance, only he can see the alterations, whereas everyone else can only see the effects).
 * So Calvin has Stupendous-Delirium? Harsh.
 * Nah, when he grows up he'll be able to extend this power so that he can cast illusions/warp reality for other people, too. When he put his mind to it, he could make Moe see Hobbes, too.
 * She has taken away the Stupendous Man costume a few times. This was probably to teach Calvin to use his powers wisely.

Calvin is a Spark.
He is able to create a variety of fantastic inventions, all of which work, and uses his appearance as a 6-year-old to throw people off when he's in melodrama mode as a result of his madness. Hobbes is a product of this insanity, who actually aids Calvin in the creation of his machines.

Hobbes doesn't have to turn stuffed when anyone other than Calvin looks at him -- he just chooses to.
Like the toys in Toy Story, he can move around in front of other people, but is afraid that he will be confiscated and treated as a freak or shut up in a lab.

Calvin's dad knows Hobbes and Calvin can interact, and the origin of Hobbes' capture in the first few strips is his doing.
Calvin's dad used to own Hobbes, and still remembers talking to him, but knows that no one will believe him if he says so. He loves Hobbes and would never get rid of him, but can't play with him anymore, so he tied Hobbes up in a tree, planted the idea of capturing a tiger in Calvin's head, and then, while Obfuscating Stupidity, prodded Calvin into making Hobbes into a friend. Hobbes and Calvin's dad planned this out together and are keeping it a secret from Calvin until he's ready to give Hobbes up. Eventually, Calvin will do the same thing for his kid.
 * In addition, Calvin's dad and Hobbes either have an agreement that Hobbes will appear stuffed when Calvin's dad is in the room, or that Calvin's dad will pretend to not see Hobbes as real. Or perhaps, Hobbes can only be seen by one person, and will never be able to be seen by Calvin's dad after being given to Calvin.

Calvin is related to Christopher Robin on one of his parents' side.

 * Option A) If it is his mother's side, it explains both Calvin's ability to interact with Hobbes and his mother's occasional manifestation of this ability -- it's genetic. However, these genes stop expressing themselves after a few years, so while Calvin's mother used to communicate with her own toys all the time, she's forgotten and her ability barely functions anymore. Christopher Robin never told his granddaughter about this, because he's forgotten, just like she has.
 * Option B) If it's his father's side, it explains why Hobbes' personality is so much like Calvin's Dad's -- Hobbes is very old, made from the rags of Tigger, and has been passed down from Christopher Robin to his son, to Calvin's dad, and the personality traits run in the family, causing Hobbes to pick up on them. If this is the case, Hobbes used to be a toy of Calvin's dad, who also could communicate with Hobbes, and has memories of this even though he thinks he just made them up.

Toys like Hobbes die when their kid owners stop believing in them.
Hobbes is aware of this, and subtly keeps attempting to defy all possibility of Calvin being able to brush his experiences with Hobbes off as "imagination" by creating paradoxes, like tying Calvin to chair, so Calvin will believe in him/keep him alive longer.

The identity of the famous Noodle Incident was...
An Accidental Kiss via spaghetti (noodles) a la Lady and the Tramp. The recipient? Susie Derkins. That Didn't Happen, obviously. Or, if that's too squicky, she dropped her lunch and he shared his noodles with her... point being, it wasn't a prank. Calvin would be proud of that.
 * The noodle incident was clearly something morally wrong, because Hobbes mentions it when Calvin states that he's been good all year. Those two theories just aren't bad enough.
 * In that context, Sinfest's theory of an Unusual Euphemism may make sense.
 * User:Metalitia's brother is under the impression that the Noodle Incident was a mishap either involving the brain Calvin made out of pasta for that one science project, or grossing Susie out at lunch by using manicotti to simulate his guts bursting through his chest. Somebody PLEASE help me prove him wrong. :(
 * Didn't the police get involved? Or am I thinking of some other incident?
 * Nah, couldn't have been an accidental kiss, or simulating his guts bursting out. The incident had to have been bad enough to make Calvin fear his teacher would reveal it during a parent-teacher conference ("She told you about the noodles, right?! It wasn't me! Nobody saw me! I was framed!"). It had to have been something big, something so terrible that it left him with great guilt and/or humiliation, and that would get him in a lot of trouble if it was ever found out by the general populace.
 * This troper thinks that Calvin somehow caused an explosion in the school cafeteria
 * This troper fused it with the suggestion on the It Just Bugs Me page for Calvin and Hobbes that the strips take place in a variety of parallel universes...the Noodle Incident was somehow using noodles to break spacetime and create those universes. Naturally, to those without some kind of cosmic sense, the event simply appeared spectacular and possibly illegal.
 * Calvin mentioned that nobody could prove he did it, and that would create a situation where it was obvious he did it.
 * Calvin really wasn't responsible for the noodle incident. We know he doesn't like recieving blame for things he didn't do. He doesn't like being blamed for the noodle incident because he wasn't involved.
 * Susie Derkins is probably trying to get revenge on him for something.
 * It wasn't me, Mom! It was space aliens! Honest!

The noodle incident involved Calvin breaking into the cafeteria and placing explosives inside a vat of noodles, which threw noodles all over the cafeteria's kitchen.
We all know that Calvin hates the food at his school's cafeteria, and Calvin has tried to obtain explosives so many times, it must have happened once. Think about it; nobody could prove that he did it if he set the explosives on a timer, and it is bad enough to invoke the wrath of Santa and for him to be scared of his teacher telling his parents about it. His teacher would tell his mom about it because of Calvin's bad reputation, but she would still not be able to prove Calvin did it.

The chain letter has something to do with Calvin's baldness arc
The letter said "A man broke the chain and went bald", and since he trashed the letter, fate went out of its way to cause Calvin to have his hair cut short enough to be bald sometime later.

Hobbes is a personification of Calvin's personality in several years
Hobbes' personality was created by Calvin long ago and embodies his latent maturity. In several years Calvin's personality will begin to resemble that of Hobbes (assuming that he ever ages).

The guy with the glasses is not Calvin's real father.
He knows it, his mom knows it but is in denial, Calvin does not know for sure but has had suspicions from day one, and Hobbes may or may not be aware but is keeping quiet about it either way.
 * Dammit, now I'm reading that as That Guy With The Glasses is not Calvin's real father. Holy crap, could that mean....

Going with the above theory, Calvin's real father is Rocky.
His mom is Janet, and the other guy is Brad. The reason that Calvin came out the way he is has something to do with the fact that he is the offspring of an Artificial Human with half a brain.

Calvin has ADHD
Heck, he's practically the poster child for ADHD.

Hobbes is Calvin's Stand.
And yes, there is such a thing as a Stand User born with a Stand (the most notable examples being Avdol, Kakyoin, N'Doul, and the D'Arby brothers). It may just have been impossible for Hobbes to manifest until Calvin got the tiger plushie, which Hobbes was able to bind himself to. And yes, there are Stands which can act and think independently of their Users (q.v. Baby Face...or at least its homonculi...Echoes Act III, Dragon's Dream, Sex Pistols, Gold Experience Requiem).

Calvin and Hobbesis an allegory for Gnosticism.
Calvin's father is Pleroma, Calvin's mother is Sophia, Calvin is Sammael, Hobbes is an Archon, and Calvin's fantasies represent the material world.
 * Rather: Calvin's day-to-day life represents the material (false) world created by the demiurge, while his fantasies are temporary breakthroughs to the true ultimate Reality.

Calvin's parents die when he is 12, he is adopted by a rich couple, and he spends his teenhood with them, and changes his name to Cameron.
He invents Ferris Bueller, and then grows up to be Jack, in Fight Club.

Yeah, He hasn't had a great mental life. Poor him.

Hobbes used to belong to Calvin's Mom.
As the above 'Calvin and his Mom are Gods' theory states, Calvin and his mom were most likely similar as children. And she does communicate with Hobbes twice (raccoon arc and Yukon arc anyone?). It's very possible that Hobbes was her old stuffed tiger and playmate from when she was a child, and when she lost the 'ability' to see and hear him like she used to she handed Hobbes down to Calvin.

Calvin never ages because he has psychic powers.
Similar to that one Twilight Zone episode. Calvin uses his powers to prevent anyone in the town from ever aging, and no one ever suffers lasting consequences because Calvin is merciful. Praise to be Calvin.
 * Well, we all know what that means...

We Have Entered an Endless Recursion of Time.
And it ends, only to begin again...

Hobbes is actually a real person, the rest are just fantasy.
Hobbes is really just imagining the whole thing since he doesn't get that much of a chance to be snarky as a imaginary tiger.

Calvin grows up to be Ellis.
And of course, Hobbes is Keith. I'm not sure why, but this just fits for me, somehow. Ellis is simply Calvin's last name, and for whatever reason, he starts going by it when he grows up.
 * Wait... Calvin Ellis? Cal Ellis? Cal El? Kal-El? Oh my god! Calvin is Superman, and the comic is an Elseworld of Smallville! Hobbes is merely the creation of a version of the Man of Steel with reality-warping powers!!!!
 * And in one line from the game (on the elevator in Dead Center) Ellis states that some people call him Ell, which helps validate your theory.

Calvin and Hobbes are actually John Calvin and Thomas Hobbes
After they died, they were each sent to an alternate universe to prevent them from getting into heaven (Calvin so that he wouldn't convert everyone in heaven to Calvinism and Hobbes so that he wouldn't try to declare himself supreme ruler of the universe). For some reason, Calvin had his age permanently reduced to 6 years old and Hobbes was transformed into a stuffed/occasionally non-stuffed tiger. Calvin eventually went crazy attempting to rationalize this during the approximately 100 years between his death and Hobbes's, while Hobbes just assumed that he had always been a tiger and had only dreamed he was a human. Of course, this would also imply that God has a big problem with Calvinism for some reason, and that writing Leviathan was part of a plot for World Domination...
 * That cracks me up. You just made my week.
 * I actually have a t-shirt of them as John Calvin & Thomas Hobbes. For real. They sell those things. I don't know where, it was a Christmas present.
 * Right here. You're welcome.

Hobbes is Cthulhu, or some other Great Old One
Hobbes is capable of incredible strength(frequently besting Calvin in fights, although Calvin is only a kid) and careful tactics. He is fairly intelligent and mature, and nobody knows he even exists except Calvin. However, because Hobbes was able to tie Calvin to a chair(you can't tie yourself to a chair) it is very obvious that Hobbes actually does exist. The explanation is obvious. Hobbes is Cthulhu, or some form of Great Old One. The reason Calvin frequently daydreams is not because he's a kid with a vast imagination, but because he was driven insane from being able to comprehend Hobbes's true form.
 * Keep in mind that "besting Calvin in fights" isn't all that impressive, because Calvin is a six-year-old, and Hobbes is a tiger. Also, daydreams don't qualify as insanity by a long shot; it's perfectly reasonable for a six-year-old to pretend to be a dinosaur or a space explorer.

Calvin is a Genius, as are both of his parents.
Calvins parents are retired geniuses, his father perhaps disillusioned or frightened of becoming Illuminated. When they had Calvin his mother, also retired but with far less fear/concern gave Calvin a special mane bound into a toy tiger, possibly intended to be a guardian but instead it caused Calvin to manifest his genius. His mother is actually interested in this and is studying it as Calvins reality warping is much stronger and potentially more generally useful at his age than has ever been seen (this might also be why he tends to remain in his imaginary constructs around his mom but not so around his father). His parents don't mind that he's alone frequently as it avoids him accidentally creating Igors (they might even be quietly encouraging Calvin's behavior because it means that he won't accidentally awaken or break someone who sees him doing mad science)

In addition, Calvins dads comments that Calvin's various miseries and frustrations are to 'build character' is actually literal. Given how young Calvin is he is terrified that Calvin would be easily consumed by mania and made illuminated, so he's trying to give Calvin a strong personality and background as fast as he can, and do it away from technology to avoid it backfiring, it still does, just for other reasons. Calvins various forays into dreamworlds are actually him wandering between realities, the spaceman spiff universe his favored destination, but sometimes he has found others as well, like when he found he was a test subject with alien creatures using a hand puppet shaped vaguely like his mother. The times where he has mentioned seeing his mother in a superheroic costume, or where he found a remote that led to his parents being crimefighters are actually true events, but they have manipulated things so as to him not realizing it, mostly for fear of him using it himself.

Calvin is Rosalyn's kid.
Rosalyn got pregnant in high school, and gave her baby up for adoption so she could continue her pursuit of education. But she still cares about him so she keeps babysitting him (come on, would anybody but a mother look after that child?). Also, Calvin has an Oedipus complex, hence Suzie.
 * I think at some point she's established to be 16.

Of course, she's evil, (which is where Calvin gets it from) which explains first, why she keeps charging ridiculous amounts of money to babysit, and second why Calvin fears her enough to treat her like his real mom. Of course, since they're both beings of evil they understand each other to an extent, leading up to when Rosalyn spent a touching night bonding with Calvin over a game of Calvinball (much to his fosterparent's disbelief; remember, they don't know who his mom is).

Who's the father? Why, Hobbes of course. Rosalyn's into furries. And Hobbe's aiding and abbeting of Calvin's mischief is probably why Rosalyn is now dating Chuck.


 * To be honest, the theory almost sounded plausible until the third paragraph.


 * Agreed. The first two paragraphs are solid, the third is just guesswork (though, I suppose it is plausible).


 * Huh. Suddenly Calvin's dad repeatedly saying 'I wanted a dog, but noooo...' is cast in a new light.

Eventually this happened.

 * I'm tearing up now...

Alternatively, Turns out this happened.
Less Crowning Moment of Heartwarming, more Tear Jerker.
 * Then, this happens and the Crowning Moment of Heartwarming comes right back.

They both happened.
And sometime between those events, this happened.
 * The link above is now dead, but you can still view the comic via Google cache.

Susie is actually Daria Morgendorffer
This theory is sort of a continuation to the "Calvin dies in the last strip" and "Calvin and Susie are in love" theories. After Calvin dies, Susie is heartbroken, so her family moves to Highland to get her away from that neighborhood, and those memories. Susie/Daria recedes into her books while waiting in vain for another kid like Calvin to come along. Also, due to her family having to pack up and move so suddenly, her dad has to take the first job he finds, which explains the horrible job/boss alluded to in Boxing Daria.
 * Having to deal with both Calvin and Beavis and Butthead at the same time? Poor girl.

Calvin has childhood-onset schizophrenia.
Hobbes is his first "imaginary friend". Eventually, he'll get more and more... and they'll tell him to do things...

Hobbes is Real, but all the Humans are actually dolls.
Hobbes has a great imagination, but he's often made fun of by the other tigers for playing with his man-dolls.

Calvin's Mom's real name is Daisy. His dad is the guy in the song who sings about a "bicycle built for two."
Calvin's dad likes bicycling so much, I could imagine him as a teenager trying to woo Calvin's mom with the idea that "nothing is more romantic than a bicycle built for two."
 * That sounds less like a WMG and more like the premise for an adorable fanfiction. I suggest that Calvin's parents are named Joyce and Eliot.
 * Which--to those not "in the know"--sounds like a Gender Flip. Clever...

Calvin becomes The Joker
"You know, you remind me of my father. I hated my father."

"Wanna know how I got these scars?"

Calvin's father, concerned about his son's development, decides that the stuffed tiger that he spends so much time with has got to go, so he decides to destroy Hobbes by cutting him to bits. Calvin watches in horror and tries to save Hobbes, but his father shoves him away, accidentally cutting the sides of his mouth in the process. A now physically and mentally scarred Calvin ends up killing his parents later on as revenge, which sets off his life of crime.


 * And going by the above theories, that means The Joker is God.

Calvin’s good duplicate is Linus
When the good duplicate had an evil thought, he disappeared. Calvin and Hobbes interpreted this to mean he simply evaporated, however he actually was transported through time and space to the Peanuts universe, where he was born as Linus. Look at them. They have identical fashion sense (black shorts, red striped shirt, hair combed flat) and they’re both dutiful, polite, and highly intelligent for small children.

Now here’s the kicker: the reason why the good duplicate is “good” is because the duplicator copied Calvin, then subtracted his overactive imagination. This is both a blessing and a curse for the duplicate when he becomes Linus: on the one hand, he’s able to form stable friendships with real people like Charlie Brown, which Calvin could never do, on the other hand, he is unable to imagine the Great Pumpkin into literal existence like Calvin did with Hobbes.

Later on, Linus managed to build a working duplicator, which is where Rerun came from.
 * This WMG also explains Linus's obsession with his blanket. It's latent memories of Hobbes, manifested as a security blanket.

Calvin's Mom is able to percieve Hobbes as "Real"
Mom at times does try to communicate with Hobbes, though it's brushed aside as a momentary thing. She also never tries to tell Calvin that Hobbes isn't real because not only can she not bring herself to tell her socially awkward six-year old to give up the only true friend he has, she can't convince herself that Hobbes is merely a stuffed toy.

Calvin is a young Doctor Horrible
And if it's true that they are both split personalities, Calvin's personalities changed, and Doctor Horrible and Billy formed,

Does that mean Calvin and Hobbes still exist in some corner of Doctor horrible's mind?

Calvin's Mother's Side of the Family is Made of Wizards and Witches
His maternal grandma is the sister of Draco Malfoy's grandfather. She moved to America and married a Muggle to rebel against the Malfoys (who Calvin get's his blonde hair from). Hobbes and the other "imaginary" events are actually underaged magic caused by Calvin, who is extremely powerful by wizarding standards. The vents are disguised from Muggles by a variation on the Disillusionment Charm cast by Mom. Calvin will become a Gryffindor. Susie might also be a witch, but she pretends to be normal and straight laced to hide this. Calvin being blasted into the air and having his clothes knocked off in their snowball fights are her underaged magic. They will go to Hogwarts, Calvin will become a Gryffindor and Susie will be a Ravenclaw. Mom was a Hufflepuff. Calvin is the child of another prophecy and he, Hobbes, and Susie will battle the next Voldemort. Ms. Wormwood takes the place of someone who died or retired and is now a Slytherin teacher. Rosalyn is the Gryffindor Quidditch Captain.

Calvin's last name is Coolidge
Hey, he could have matured. Although, given how Calvin talks about 1988 whenever he shows his dad the latest polls...

Calvin is in some way related to Phineas and Ferb.
Think about it. Eccentric imaginations, possible time lords, and they have anthrophomorphic animals as friends. (Perry and Hobbes).

AND if you follow one of the guesses above, Calvin and Hobbes, Phineas and Ferb, and Ben 10 are all related!

Hobbes is a malignant stand (a la Jojo'sBizarreAdventure).
Seriously. Just consider all the facts. First regarding stands: 1. Anyone can have a stand, and stand ability can appear unpredictably. 2. Although there are exceptions, stands tend to be made of nonphysical energy and cannot be detected by human senses. 3. A few stands are rooted somehow to mundane physical objects, most notably Wheel of Fortune. 4. Only things that can damage nonphysical entities can harm a stand; corporeal trauma does no damage whatsoever. 5. A stand must always remain within a certain distance of its wielder. 6. Under certain circumstances, a stand can be harmful to its wielder, whether a deliberate act of self-destruction (N'Dool) or being malignant for some reason (Holly). (Hirohiko Araki did a handwave about "lack of a powerful fighting spirit" to explain Holly, but that doesn't hold up in the face of Hol Horse or the Sun wielder, much less Kenny G.) 7. Stands tend to take on the personalities of their wielders, particularly the ones that can speak on their own. 8. Even the weakest stand is tremendously powerful; the mightest stands can alter time itself (as spectacularly demonstrated at the end of both the 5th and 6th stories).

And regarding Hobbes: 1. Both versions of him are real (as Watterson himself stated in the 10th anniversary special). He does not transform from a stuffed animal to an anthromorph and back, nor is he a purely imaginary construct. What Calvin sees and what the rest of the world sees are what they see ALL the time, and both are perfectly logical from their respective POVs. 2. His anthromorph self can move a certain distance from his stuffed animal self and Calvin but always occupies the same general area. If Calvin and the stuffed animal are separated, the anthromorph simply does not appear. 3. He's sentient, highly intelligent, and ambulatory. He's also very fast and agile, and considerably stronger than Calvin. 4. He's not a natural tiger and in fact displays numerous traits that are extremely bizarre for the species (e.g. his obsession with tuna). 5. He's slammed headfirst into heavy objects, tumbled down cliffs, and had heavy objects fall on him, and he's never suffered worse than mussed-up fur and a few little scrapes. 6. He's basically an egomaniacal sociopath. He's utterly self-centered, shameless, stubborn, arrogant, condescending, and narcissistic. He cares only about himself and never shows the slightest concern for Calvin. In fact, he loathes doing anything that would benefit Calvin even if it would be completely natural for him (mauling Moe, for example). He takes delight in tormenting, bullying, and outright abusing Calvin. 7. He is obsessed with violence; exhibit A, playing full-bore collision football with someone clearly out of his league, exhibit B, pulverizing Calvin for the slightest excuse ("You moved downwind, silly!").

The conclusion is clear: Hobbes, the talking tiger, is a highly malignant stand that Calvin unwittingly created from a stuffed animal he received as a present. Because Calvin is so selfish (and uncontrollable), it only makes sense that any stand created by him would be the same, only cranked up to about 22. Because Hobbes is rooted in the stuffed animal and has only a partial connection to Calvin, tormenting or even killing Calvin does not endanger his existence, and he can indulge his base desires to his heart's content. Calvin, being far too stupid to comprehend Hobbes true nature, only sees him as a somewhat unusual friend and can't understand why no one else can see what he does.

Calvin's mum is Andy Fox from Foxtrot
Here's my theory. Calvin's mum is 18 years old and studying English at college when she meets Calvin's dad, who's a bit older at 25. They fall in love, get married, and 9 months later have a kid named Calvin. Calvin's mum drops out of uni without completing her degree, and becomes a stay-at-home mum. This causes some angst with her mother, and so the two stop talking, and Calvin's parents move states.

She likes healthy cooking, and often serves food to Calvin that he doesn't like. Both her and Calvin's dad care about the environment, so they keep the thermostat low in winter, much to Calvin's annoyance.

6 years later, when Calvin's mum is 24, Calvin dies in a sledding accident. His parents, heartbroken by grief, move states. They spend their time eating junk food, and don't exercise as they are too depressed to do anything. Sadly, Calvin's dad dies some months later as a result of a heart attack.

Calvin's mum moves again, back to her home state. She decides to go back to college, gets her degree in English Literature and gets a part-time job at the local paper, as a writer. Realising that life is short, she gets into contact with her grandmother again, but the relationship is still somewhat strained. She meets a man named Roger Fox. Calvin's mum gets pregnant, and so they get married. Calvin's mum is 26. She gives birth to a healthy young boy named Peter.

Two years later, Paige comes along, and then Jason.

Calvin's mum is still saddened by the death of her last husband. She knows that junk food caused his untimely demise, and so swears to only cook healthy foods, so her children remain healthy. Proving that old habits die hard, she continues to keep the thermostat low during the winter.

Eventually, we join her adventures as matriarch of the Fox family. She's 42, Roger's 45, Peter's 16, Paige is 14 and Jason is 10.

Calvin is in Wonderland.
Reffering to the above idea, when Calvin's body died Hobbes took pity on him and returned to his home country (Wonderland) with Calvin's soul in tow. And there he stayed until Jason recreated the portal that took Alice to Wonderland...at the same time Calvin's became an experienced monster hunter and wishes to read Captain Napalm again.

Calvin grew up to be Sarge
The belligerence and vivid imagination are there, and he is pretty clever under all that cloudcuckoolanderism. Plus there's the fact that most of his strategies tend to resemble a giant, for-keeps game of Calvin Ball.

Calvin grows up to be Kamina
[http://i35.tinypic.com/25roxup.jpg Perhaps the greatest evidence for this is in the strip where Calvin's out shopping with Hobbes and his mom, and Hobbes is watching him try on sunglasses. Notice anything familiar about the pair he's seen wearing as his mom sends him back to the rack?] Additionally, they're both adventurous, boistrous, loudmouthed, and violent. Also, look at Calvin's hair - three spikes sticking up. Now look at Kamina's - three spiky bangs over the forehead. Therefore, eventually he decided to slick that part down. Not to mention that Kamina's tactics are pretty much Indy Ploys, and he gets things done solely because he thinks they should, rather than what would logically happen. Pretty fitting for someone who had an overactive imagination as a kid, huh?

After the events of the strip, as Calvin got older, some cataclysm occured that caused humanity to move underground, however, Calvin's father, being the character-building "no-pain-no-gain" advocate he is, insisted on returning to the surface. Calvin declined, but as time went on, he resented his choice, and went on his path of ROW ROW FIGHT DA POWA, creating a new identity for himself by dyeing his hair blue, getting tattoos, and getting around to buying a pair of sunglasses just like the ones he coveted as a child, in addition to renaming himself Kamina. Hobbes was his Team Pet and equivalent of Boota until they were parted somehow some time before he met Simon and went on his adventures with him. Eventually, however, having forgot his childhood membership of Get Rid Of Slimy Girls, he ended up falling in love with Yoko until they kissed. This triggered memories of his old club, which set him off-course for a little while, a condition that ultimately costed him his life, but not before he became a great hero of mankind and motivated his young pupil to take over Team Dai-Gurren and save the universe.

As for why Kamina supposedly has never been to the surface, he just got amnesia and forgot much of his life at age 6 for a time.


 * Alternatively, Calvin is Simon (replacing Boota with Hobbes).
 * If you want to get really out there, Viral could be an evolved Hobbes, much like how Guame evolved from a Boota-like pet armadillo to his present form, or how Boota became a Petting Zoo Person in the Multi-Dimensional Labyrinth. After all, Viral is catlike, and it'd explain his fixation with Kamina...
 * A probably irrelevant, but still interesting fact is in the story where Calvin keeps growing. At first, he's just as big as his room, but once he gets outside, he starts to dwarf his house, then bigger buildings, then skyscrapers, and so on. In the end, he's standing on top of a galaxy. Sound familiar?

Calvin's mother is nicknamed Meg.
In one strip, Calvin gets out of the bathtub and pretends to be Godzilla. He refers to his mom as Megalon. It follows that her given name must be some variation of either Margaret or Megan.
 * Of course, this is a reference to Godzilla vs. Megalon.

Calvin grows up to be Beavis.
They're both blonde-haired juvenile delinquents, and let's face it, a lot of the stuff Beavis does is stuff that Calvin would do if anyone let him. In particular, Calvin has repeatedly attempted to get his hands on explosives, and Beavis loves blowing things up and/or setting them on fire. Eventually, as Calvin entered his teenage years, he left Hobbes behind, but without Hobbes to keep him under control and counteract his impulses, he became even worse than he was already, going about with Butthead to set things on fire and play frog baseball. Note that in the Wonderful Life episode, it turns out that without Butthead, Beavis would be a fairly normal child. Cornholio is a leftover from Calvin's childhood alter-egos. Beavis, thus, is his last name. Butthead may or may not be an older Moe, seeing as they look somewhat similar.
 * Don't buy it. Calvin is way smarter than Beavis.
 * Being around someone so moronic as Butthead instead of a sophisticated friend like Hobbes will do that to you.

Calvin is a troll.
Specifically, he's an albino, which is why he doesn't have black hair and grey skin. He does, however, have spiky hair, which seems to be a common troll trait. Calvin was born with his abnormal colouration, which was declared to be an adverse trait and he was selected for culling, but he somehow managed to escape with his lusus, Hobbes, although his horns were broken off in the process. They ended up on a spaceship that travelled through a wormhole, bringing him to a planet in another dimension in the future - Earth. There, as he resembled an ordinary human child, he was adopted by a human family. Calvin must be a redblood to explain why he never gave anything away when he got hurt, and thus was born with redblood psychic powers, manifesting in him unconciously creating illusions to make his lusus look like a stuffed animal to everyone else. His Foe Yay with Susie is his interpretation of kismesisship - since he was raised by a species without that concept, he doesn't know the details, but his inborn psychology sees hate as a type of romance. Spaceman Spiff is his recollections of being a citizen of an intergalactic empire, and he sees monsters under his bed because he doesn't have a recuperacoon to prevent the nightmares that naturally affect his species. The top evidence here is that in one strip, Calvin, at Hobbes's suggestion, asks his mom if he was ever a grub. What Hobbes knows and his mother doesn't is that he actually was.
 * Actually, he asked his Mum because his Dad told him that he was a grub and pupated at age 2. When she said he didn't he goes back to his Dad and says "You'd better get your stories straight with Mom, Mr. Britannica!"

Calvin grows up to be the tiger guy from That CSI episode
Okay, bear with me on this one. Calvin likes playing pretend just like every other kid, right? However, he does so a LOT more than most normal children. It's implied that his only friend is Hobbes. He's even dressed like a tiger and transmogrified into a tiger on more than one occasion. It's not too much of an exaggeration to say that if Calvin did become a furry, Hobbes would be his fursona. The guy from the CSI episode in question is holding a presentation about... something or other, but he says things like "The child indulges in fantasies of being a tiger, but in his dreams runs from the tiger for dear life." Calvin, as stated, has tried being a tiger multiple times, yet he's normally being pounced on by Hobbes.

Calvin eventually became a math whiz
Calvin outgrew his difficulties with mathematics and other school subjects... and thus he created CALVINHAMMER, GOD AMONG SPORTS!

Theories as to what the "Noodle Incident" really was.

 * Calvin took some noodles to school for lunch but, instead of eating them, went into the bathroom and flushed them down the toilet. This clogged the toilet and created tremendous havoc, which, knowing Calvin, pleased him greatly as was his intention. He told Hobbes about it, which is why Hobbes refers to it in the strip. The reason why no one can prove that he did it is because no one was in the bathroom when he flushed the noodles.
 * The Noodle Incident didn't actually happen. It was a crazy story Calvin made up that he told Hobbes. Hobbes believed it, and he references it later in the strip because he thinks it's something that actually happened.
 * There's a problem with this one - in one strip, it was established that Santa Claus knows about the Noodle Incident, as far as I remember.
 * This troper usually had the mental picture of a tidal wave of noodles, like if Calvin opened up a steampipe next to a crate of dried noodles in the cafeteria kitchen, causing them all to boil and expand, flooding through the kitchen and into the cafe. Everyone suspects him but can't actually prove it.
 * One of Calvin's alter egos, acting through Calvin, caused Tommy Chestnut to be served with pasta in the school cafeteria. Hobbes complained of Tommy Chestnut's lack of hygeine, so presumably he didn't eat all of him. Calvin got away with it because his dad's a lawyer. Later, when Calvin enters the traffic safety poster contest, he splatters his poster with "chunky spaghetti sauce" to remind everyone of the Noodle Incident and intimidate the judges into awarding him the prize.
 * In an earlier strip (if I'm correct, it was much earlier in the strip)Calvin had to do a report on the brain, and his visual aid was a bag of cooked noodles. After the project, he accidentally left it in his locker/desk/random place for a while, and when he (or someone else if he didn't really do it) found it, now all moldy, stale, and gross, whatever happens to noodles left to rot, he (or if the true perp was a she) got an amazing idea.... and the rest is history, though we can guess that from one strip (where Calvin was sent home around lunch, Calvin states he doesn't want to talk about it, though Hobbes asks whether or not it had to do with all the sirens he heard around that time) may have involved the police, the hospital, and/or the firefighters....

Calvin is attempting to perform Inception on one, or both, his parents

 * Calvin created the dream world, Hobbes is either Calvin's totem or someone who can change shape, like Eames, and Susie is just Calvin's projection of the real Susie. This obviously takes place over multiple sessions, and Calvin elects to end the sessions not with Je Ne Regrette Rien, but by purposely killing he and Hobbes in the sled. The idea he's incepting into his parents' minds? Imagination is good.

Hobbes is a living being, albeit one capable of manipulating his own orgone energy
When he's just with Calvin, he functions normally, but when anyone else is around, he vents off his own orgone energy so that he just looks like a stuffed animal. Calvin's transmogrifier may work on the same principle.

Calvin and Hobbes and Garfield take place in the same universe.
The connection is Lyman. He disappears from Garfield in 1983, then a few years later reappears in Calvin & Hobbes. Lyman is Calvin's Uncle Max: his full name is Max Lyman. The evidence is that Max and Lyman look the same, and have a similar sartorial taste. The few differences between the two (such as Max's bigger nose) can be explained by different artistic impressions of the same character. Max's hairline has receded somewhat since he was living with Jon, but there are years between his disappearance from Garfield and reappearance in Calvin & Hobbes, so that certainly could've happened. Max being Lyman also explain why he's worried about Calvin's imaginary friend, and why he says that all of his friends might've been imaginary too. When he was living Jon, they were caught up in a folie à deux, where they imagined their cat and dog were acting like human beings. Max realized he had to break away from this fantasy, but Jon, being the more infantile of the two, couldn't do the same. Max realized he had no choice but leave: that's why he disappeared so suddenly from Garfield and left Odie behind. His past history explains his comment about imaginary friends (he's referring to Garfield an Odie), as well as why he thinks Calvin having an imaginary friend might not be healthy for him.

Either Calvin or Hobbes is a Time Lord, maybe both are.
The TARDIS is the cardboard box, because it has been used to time travel on two separate occasions. And the Magic Carpet that Calvin and Hobbes once used is the TARDIS that has changed form.

Susie is actually Mom and Dad's daughter, and was Switched At Birth with Calvin.
While Calvin's parents are questioning whether this kid is really their son, notice how Susie looks like a young version of Mom, and shares Dad's romantic imagination, bad temper, and mischievous streak.
 * More support for this theory: both Mom and Dad have dark hair, while Calvin's hair is blond.
 * Having a blond child with dark-haired parents isn't that uncommon.

Calvin gets lost in the woods and dies of hypothermia.
"Let's go exploring!", indeed.

Calvin's Dad is a Vietnam Vet.
First of all, he is drawn and implied to be in his forties. In one strip, he mentions he hates being saluted. His "temper" is just something he adopted then to keep the people who served under him in line. His obsession with fitness is a form of OCD, which he suffers from due to his experience during the War. His somewhat child-ish acts and his imagination are defense mechanisms he adopted because of the trauma he went through.

Calvin's time machine also allowed travel to parallel universes, accidentally or by design.
As you can see here: http://www.sinfest.net/archive_page.php?comicID=3227

Calvin grows up to be Willy Wonka
I really hate all these theories saying horrible things about how Calvin is insane or something and grows up to be the Joker or Fight Club guy. calvin isn't crazy, he just has an incredible IMAGINATION. Which is why I think he'd grow up to be Willy Wonka. The cardboard box is the prototype for his great glass elevator. You may say that Charlie and the Chocolate Factory takes place before Calvin and Hobbes but Calvin can time travel! He went back in time to find Hobbes, who had gotten lost in a time warp (and spent the rest of his days living with a motherly kangaroo and her cute little son) but never found him, so he settled and made a chocolate factory. Charlie Bucket is Calvin's ancestor.

The snowstorm from the last strip killed (almost) everyone, leaving Calvin and Hobbes as the only survivors.
"A fresh start" indeed.

Calvin is Q Jr. from Star Trek: Voyager...
And Q is Hobbes! After the Continuum told Q he had to stay by his son's side for the rest of eternity, Q created this version of Earth. He may have made it as an attempt to reign in his son a little, or maybe he just made it to have fun. It allows for all the seemingly impossible things that happen (such as evil bikes and baseballs, and I swear those duplicates Calvin made with just a cardboard box really existed), and it lets everyone stay the same age year after year. Maybe the rest of the inhabitants, such as Mom, Dad, and Uncle Max, are actually closer to holodeck characters than actual beings.
 * The transmogrofier then malfunctioned and turned Hobbes into a donkey...dragon...THING, and he became evil, renamed himself Discord, and started tormenting the My Little Pony characters.

Calvin is a Gender Bended Molly, or vice versa. Hobbes is the Entei.
An obnoxious, overly imgainative, blond kid, and a imaginary but extremely lifelike wild cat. It's obvious.
 * Oh yes, and Uncle Max was sucked into the Unknown portal.

Hobbes is distantly related to the Weeping Angels.
Whenever anyone except Calvin sees him, he turns into a stuffed animal.

Calvin grows up to be Skippy.
Just a thought. I mean, seriously! check out some of these things and tell me that they don't sound like Calvin. Especially number 142.

Calvin grows up to be Spaceman Spiff
The Spaceman Spiff strips are real time, while the Calvin strips are flashbacks to when he was a child. Many times, these flashbacks are things that remind him of the situation he is currently in.
 * Jossed. Look at this strip and see Calvin blantantly waking up from the SS sequence.
 * Still... I think that could just be a very sudden flashback. I do like this WMG though.

Susie sees Mr. Bun the same way Calvin sees Hobbes.
The reason we as the audience don't see him as alive is because the strip is from Calvin's point of view, and he can't see Mr. Bun the way Susie can, just as she can't see Hobbes the way he does.

Calvin is a grown-up who has never passed first grade.
He has a ridiculously large vocabulary for a six-year-old. At one point Miss Wormwood gives a problem asking him to calculate how far apart two cars started given their speeds and when they pass; this is not a first grade problem. She must have thought he'd do better if he were more challenged. He has well-informed political opinions. When he drew a Stegasaurus in a rocket ship his teacher said it wasn't "serious". Who says that to a little kid? Calvin can't possibly be a kid except in his imagination.

Calvin and Hobbes takes place in a world where people have no imagination.
This is a good guess on the fact that everyone thinks Calvin is so weird, they have no imagination! After the final strip, they called the government to take Calvin away and see what in the world was wrong with him, and, after examining him for quite some time, they realized that Calvin was happy when he was being creative, (his various inventions, his amusing snowmen), so they had everyone in town and used a special device to implant imagination into their heads, and Calvin's town became a much better place, and Calvin was hailed as a hero.

Calvin is an alternate, male version of Elizabeth.
Hobbes is real, and is there because of Calvin opening tears between his Earth and his own...the lack of training with this though could explain why Hobbes can only be seen by him.
 * Oh, and the time travel adventures are real, the power to go there was just in him the whole time.