RONALD FISHER: Why does it have to be a chicken? Why not a frog, turkey, or pig? We randomly try to a have chicken, frog, turkey and pig cross the road 10 times each. We then compare the mean number of times each animal crossed the road to determine if there's a difference in means.
SARAH PALIN: The chicken crossed the road because, gosh-darn it, he's a maverick!
BARACK OBAMA: The chicken crossed the road because it was time for change! The chicken wanted change!
JOHN McCAIN: My friends, that chicken crossed the road because he recognized the need to engage in cooperation and dialogue with all the chickens on the other side of the road.
HILLARY CLINTON: When I was First Lady, I personally helped that little chicken to cross the road. This experience makes me uniquely qualified to ensure right from Day One that every chicken in this country gets the chance it deserves to cross the road. But then, this really isn't about me.
GEORGE W. BUSH: We don't really care why the chicken crossed the road. We just want to know if the chicken is on our side of the road, or not. The chicken is either against us, or for us. There is no middle ground here.
I agree with George.
COLIN POWELL: Now to the left of the screen, you can clearly see the satellite image of the chicken crossing the road.
BILL CLINTON: I did not cross the road with that chicken.
JOHN KERRY: Although I voted to let the chicken cross the road, I am now against it! It was the wrong road to cross, and I was misled about the chicken's intentions. I am not for it now, and will remain against it.
DR. PHIL: The problem we have here is that this chicken won't realize that he must first deal with the problem on this side of the road before it goes after the problem on the other side of the road. What we need to do is help him realize how stupid he's acting by not taking on his current problems before adding new problems.
OPRAH: Well, I understand that the chicken is having problems, which is why he wants to cross this road so bad. So instead of having the chicken learn from his mistakes and take falls, which is a part of life, I'm going to give this chicken a NEW CAR so that he can just drive across the road and not live his life like the rest of the chickens.
NANCY GRACE: That chicken crossed the road because he's guilty! You can see it in his eyes and the way he walks.
MARTHA STEWART: No one called me to warn me which way that chicken was going. I had a standing order at the Farmer's Market to sell my eggs when the price dropped to a certain level. No little bird gave me any insider information.
JOHN LENNON: Imagine all the chickens in the world crossing roads together, in peace.
BILL GATES: I have just released eChicken2010, which will not only cross roads, but will lay eggs, file your important documents, and balance your checkbook. Internet Explorer is an integral part of eChicken2010. This new platform is much more stable and will never reboot.
AUGUST MOBIUS: To get to the same side.
ISAAC NEWTON: Chickens at rest tend to stay at rest. Chickens in motion tend to cross the road.
WERNER HEISENBERG: We are not sure which side of the road the chicken was on, but it was moving very fast.
JERRY SEINFELD: Why does anyone cross a road? I mean, why doesn't anyone ever think to ask, "What the heck was this chicken doing walking all over the place anyway?"
AL GORE: I will fight for the chickens and I will not disappoint them. Did I mention that I invented roads?
KEN STARR: I intend to prove that the chicken crossed the road at the behest of the president of the United States of America in an effort to distract law enforcement officials and the American public from the criminal wrongdoing our highest elected official has been trying to cover up. As a result, the chicken is just another pawn in the president's ongoing and elaborate scheme to obstruct justice and undermine the rule of law. For that reason, my staff intends to offer the chicken unconditional immunity provided he cooperates fully with our investigation. Furthermore, the chicken will not be permitted to reach the other side of the road until our investigation and any Congressional follow-up investigations have been completed.
PAT BUCHANAN: To steal a job from a decent, hardworking American.
DR. SEUSS: Did the chicken cross the road? Did he cross it with a toad? Yes! The chicken crossed the road, but why it crossed, I've not been told!
MARTIN LUTHER KING, JR.: I envision a world where all chickens will be free to cross roads without having their motives called into question.
GRANDPA: In my day, we didn't ask why the chicken crossed the road. Someone told us that the chicken crossed the road, and that was good enough for us.
ARISTOTLE: It is the nature of chickens to cross the road.
KARL MARX: It was a historical inevitability.
SADDAM HUSSEIN: This was an unprovoked act of rebellion and we were quite justified in dropping 50 tons of nerve gas on it.
CAPTAIN JAMES T. KIRK: To boldly go where no chicken has gone before.
FOX MULDER: You saw it cross the road with your own eyes. How many more chickens have to cross before you believe it?
MACHIAVELLI: The point is that the chicken crossed the road. Who cares why? The end of crossing the road justifies whatever motive there was.
FREUD: The fact that you are at all concerned that the chicken crossed the road reveals your underlying sexual insecurity.
ALBERT EINSTEIN: Did the chicken really cross the road or did the road move beneath the chicken?
IMMANUEL KANT: The chicken was acting out of a sense of duty to cross the road, as chickens have traditionally crossed roads throughout history.
COLONEL SANDERS: I missed one?
RICHARD M. NIXON: The chicken did not cross the road. I repeat, the chicken did not cross the road. I don't know any chickens. I have never known any chickens.
JANOS von NEUMANN: The chicken is distributed probabilistically on all sides of the road until you observe it on your side.
BARBARA WALTERS: Isn't that interesting? In a few moments, we will be listening to the chicken tell, for the first time, the heart warming story of how it experienced a serious case of molting, and went on to accomplish its life long dream of crossing the road.
ANDERSON COOPER, CNN: We have reason to believe there is a chicken, but we have not yet been allowed to have access to the other side of the road.
DONALD RUMSFELD: Now to the left of the screen, you can clearly see the satellite image of the chicken crossing the road.
ANDRE AMPERE: To keep up with current events.
ROBERT BOYLE: She had been under too much pressure at home.
JAMES WATT: It thought it would be a good way to let off steam.
THOMAS EDISON: She thought it would be an illuminating experience.
JEAN FOUCALT: It didn't. The rotation of the earth made it appear to cross.
KARL GAUSS: Because of the magnetic personality of the rooster on the other side.
GUSATV HERTZ: Lately, its been crossing with greater frequency.
GEORG OHM: There was more resistance on this side of the road.
ERWIN SCHRODINGER: Since the wording of the question implies the absence of an observer (else the fowl's motivation might easily be deduced), it is evident that the chicken simultaneously did and did not cross the road. In the face of this, any speculation as to the bird's purpose must be viewed as mere sophistry - and as such is beyond the bounds of this discussion.
It came, it saw, it crossed.
Chickens, over great periods of time, have been naturally selected in such a way that they are now genetically positioned to cross roads.
NIGER DELTA MILITANTS:
The chicken only crossed to get her share of national cake
WORLD HEALTH ORGANIZATION:
The chicken crossing will further spread Avian Flu to another unprepared country.
NATIONAL GEOGRAPHIC: "… and as we watch the lone chicken undertake this hazardous journey, we can only wonder at the awesome nature of this dangerous, yet necessary, migration. …"
THE ROCK (WWF):
If you saw me coming, you'd be crossing the road too!
Adapted from http://stat.fsu.edu/~chicken/webfiles/q.html and a few other sources