Earlier this week, rapper B.O.B. sparked a debate on Twitter when he claimed to know for a fact that the Earth is flat (yes … like you’re gonna fall off the Earth if you go too far kind of flat). He’s certainly not the first person to think this. Historically, many ancient cultures believed the Earth to be flat, which made sense in an era when it simply wasn’t possible to prove otherwise.

Yeah. Totally makes sense.

Yeah. Totally makes sense.

But this isn’t ancient Mesopotamia. People have been to space and seen the spherical shape of our planet first hand. There’s no reason to believe the Earth is flat unless you’re completely uneducated or seriously stupid. But still, there are countless people spouting this wild conspiracy on the Internet. There’s even a Flat Earth Society dedicated to spreading what they believe is the truth about our planet. They are totally convinced that all of the world’s scientists and political leaders are lying to us for some unknown reason.

But the flat earth theory isn’t the only nutty conspiracy that’s taken off online. There are hundreds of them, but let’s explore some of the weirdest ones.

Now we just need to find Katniss Everdeen.

Now we just need to find Katniss Everdeen.

Agenda 21

Agenda 21 is the name of a plan created by the United Nations to help combat pollution and climate change and make our way of life more sustainable. It contains ideas and suggestions for developed countries to follow that would conserve natural resources and protect our environment. For some reason, a myth has pervaded online for years that Agenda 21 is actually a legally binding document that will bring about the dreaded “New World Order” and take away the private property of all Americans. Anti-Agenda 21 activists believe that U.N. plans to take over the whole world and turn every country into one giant socialist society and enslave the entire population. It’s quite a leap to make if you actually read the text of the document, yet this theory has been kicking around since the first President Bush signed the document in 1992. The Southern Poverty Law Center has posted a thorough debunking of the entire theory if you’re interested in reading more about it.

Teeth are so overrated. I'd rather have my "third-eye" open.

Teeth are so overrated. I’d rather have my “third-eye” open.

Fluoridated Water

According to some prominent conspiracy theorists, fluoride in our public tap water is being used to control the population by causing brain damage. It’s no secret that fluoride is added to our drinking water at the recommendation of the Centers for Disease control in order to prevent cavities and tooth decay. This policy has been around in the U.S. since the 1950s, and most other countries have similar policies. The low level of fluoride in our water has never been linked to negative health effects, but that hasn’t stopped nutty people from spreading weird ideas about it. Fluoride is frequently referred to as a “toxin” or as “industrial waste” by these people and they insist that Hitler used it in his concentration camps for population control. None of that is true.

FEMA can't even properly respond to disasters ... how are they supposed to accomplish this?

FEMA can’t even properly respond to disasters … how are they supposed to accomplish this?

FEMA camps

This theory is particularly odd. It purports that the Federal Emergency Management Agency (FEMA) has been building secret concentration camps across the country designed to imprison American citizens. Theorists claim the plan is related to President Obama’s desire to crown himself the absolute dictator of America and enact martial law. Once martial law is in place, millions of Americans will be loaded on to trains and sent to these shadowy facilities. No one can really explain why FEMA would want to do this, or how they would be capable of pulling off such an elaborate plan, considering their historical incompetence.

There are countless (and even more strange) conspiracies out there, each one crazier than the last. Check out Reddit for some great entertainment, but try not to fall down the rabbit hole.