In 2013, Public Policy Polling (PPP) surveyed 1,247 registered American voters on a range of conspiracy theories. This blog post looks at six of them:
| Conspiracy theory | Believe | Disbelieve | Not sure |
|---|---|---|---|
| Roswell | 21% | 47% | 32% |
| Vaccines/autism | 20% | 46% | 34% |
| TV mind control | 15% | 70% | 15% |
| Moon landing fake | 7% | 84% | 9% |
| Chemtrails | 5% | 87% | 8% |
| Lizard people | 4% | 88% | 7% |
The Roswell theory is that a UFO crashed at Roswell, New Mexico in 1947, and the US government covered it up. In fact, we now know that what they covered up was a classified military balloon project.
Many people, sadly, believe in a Vaccines/autism link, thanks to some fraudulent research. Several large-scale studies prove conclusively that there is no such link (for example, a Danish study of 537,303 children).
Many people believe in TV mind control, i.e. that the government and/or media secretly adds mind-controlling signals to TV broadcasts. Some wear tin foil hats (above) to protect themselves from this imaginary danger.
Many also believe, implausibly, that the 1969 NASA Moon landing was fake. This idea has been thoroughly debunked, and it was never very believable. For one thing, it assumes that hundreds of thousands of people around the world (including many Australians) would have kept the conspiracy a secret.
Also popular is the Chemtrails theory, that contrails seen in the sky are actually chemicals being sprayed by the government for sinister reasons. In fact, there is no evidence to support the idea, it’s ridiculous to believe that conspirators would spray themselves, the physics of contrails is well understood, and contrails have been around since World War II (as the 1943 photo above by Sgt. Stanley M. Smith, USAF proves).
Finally, the Lizard people theory is that the world is secretly run by shape-shifting lizards in human form. I cannot even imagine why someone would believe that.
The chart below shows the breakdown of the PPP results by sex, political party, race, and age (click to zoom):
This chart only shows the percentages who are sure of their belief in these conspiracy theories. The substantial “Not sure” numbers (in the table at the top of this post) are not included. The chart below shows how much more likely different groups are to believe a theory than average. The most gullible groups seem to be people under 30 and “other races” (i.e. not Hispanic, White, or African-American). African-Americans seem quite sceptical of many of the six conspiracy theories listed here (although other conspiracy theories are accepted – see the complete survey results). Republicans are slightly more likely than Democrats (14% vs 11%) to believe the six conspiracy theories listed here.
Overall, the results suggest that many people in the USA lack the ability to accurately evaluate the truth or falsity of a statement. This does not reflect well on the educational system there. That said, I’m not sure that things are actually better here in Australia.
Scientific Gems 
I know two “standard” conspiracy theorists. Standard, because there seems to be a typical “package” conspiracy theorists believe in – basically your list, plus things like FEMA death camps, nefarious purposes of fluoride in tap water and of course 9/11 being an inside job. Trying to discuss such topics with them is tiring and discouraging. They use every logical fallacy in the book to make sure they don’t have to admit the stuff they believe is unlikely at best and idiotic at worst.
I also find it fascinating that both of them, like many other conspiracy theorists, seemingly do quite well in other areas in life – they’re absolutely not stupid. They seem to have these two completely separate and different parts of the brain, one part perfectly rational, the other part completely irrational. I don’t understand how that could work inside a person’s head… (I understand that no one is completely rational or completely irrational, I’m just baffled by the strong presence of both parts in the typical conspiracy theorist)
It would be mostly innocent and even somewhat funny if they weren’t trying to convince other people to avoid vaccinations, mistrust doctors, and turn to unregulated, sometimes dangerous, alternative cures. If I see them do it on the social media I get angry and make the mistake of trying to discuss. But of course, I work for a large hospital, so I’ve been “indoctrinated”. I only wish “Big Pharma” was paying me what they seem to think they pay me…
This subject is both interesting and tiring at the same time.
It’s a worry.
It would have been nice if the survey had addressed the impact, if any, of education.