Common Misconceptions

I was told by someone once again today that "It is a common misconception that...".
What is a common misconception?
When most people think one thing, and the person stating the "common misconception" (and possibly a handful of others) thinks the opposite, and despite the fact that the majority thinks the opposite, they think they are right, and that everyone else has been mislead.
Everyone that I have heard stating "common misconceptions" knows no better than everyone else. The wise people don't give advise in the form "They're all wrong, and I'm right".
I recently read on a web page "It's a common misconception that carrots are good for you, but...". By no means am I any kind of nutritionist, but that seems a bit weird to me. (You know what also seems a bit weird? The spelling of "weird" - it should be "wierd", shouldn't it?)
I'm not saying that I think that the majority is always right. We used to think that the sun orbited Earth, and that the earth was flat, (but then again, maybe we're all wrong - we thought Pluto was a planet until recently - ha). If I thought everyone around me was wrong and I was right, and I cared about what the others thought, I'd work on proving my theory, not telling them their beliefs were wrong.
While writing this, I ended up on Wikipedia's list of common misconceptions. A few stood out:
It is a common misconception that the human body can not survive the vaccuum of space.
It is a common misconception that a disproportionate amount of heat is lost through the head.
It is a common misconception that there are successful non-surgical techniques for penis enlargement.
It is a common misconception that security lighting deters crime.
It is a common misconception that lemmings engage in suicidal dives off cliffs.
It is a common misconception that Henry Ford invented the car.
It is a common misconception that french fries originated in France.
It is a common misconception that mirrors reverse left and right.
It is a common misconception that Wikipedia is a reliable source of information (okay, I added that one)

I'm not saying that I think these misconceptions are...ummm...misconceptions. I just picked them because I think they're... interesting. I doubt there is a successful non-surgical method for penis enlargement. I doubt that lemmings are suicidal.

(I think I'm about to wander off into a nearly unrelated thread...)
This kind of reminds me of the "Philosophy - Critical Thinking" class I had to take in my first year of university. The students were made up of the usual Arts/Philosophy/Theology types you'd expect, along with a handful of Engineers that you wouldn't. The prof put a mathematical "proof" up on the overhead projector one day. It was the classic "1=2" proof. The artsy ones found great joy in this, as it clearly "proved" that all that math stuff they didn't understand, and had caused their marks to drop in high school, was infact (one word or two?) flawed. Meanwhile, all the math dorks saw that dividing by a+b when a=b is dividing by zero, which falsifies the "proof".
What is the purpose of this "proof"? To show how gullible people can be? To show how easily people can be led to believe things?
People can be very naive. I'm always surprised by how easily some people's beliefs will completely change after reading an article or watching a TV documentary, or even a mini documentaries on YouTube. They're presented with one side of the story, and take every fact they're given to be accurate. It would be interesting to observe one of these people's opinions after watching a documentary presenting one side of the story, and immediately afterwards show him or her a documentary from the opposing view.

It's very difficult not to believe something everyone else believes, and is presented over and over as the truth (see comment above about the world being flat).
Which leads me to something I believe to be a common misconception (add contradiction to the list of reasons why this is a poorly written blog post, along with lack of cohesion).
I don't think recycling "helps the planet". I think it uses way too much energy to recycle stuff; transport it to a recycling plant, sort it, clean it, melt it down, and reform it. I think too much emphasis is put on recycling, when the emphasis should be on reducing and reusing.
But I don't really care about any of this to be brutally honest (which I usually am), because I think we're fucked. We over consume. And it's getting worse. The planet is over populated and can't support our (growing) population at current (growing) consumption levels. We're told to consume, and we use our time working so we can get more money so we can get more stuff. This has been this way since the invention of agriculture, and isn't going to change. I don't thing recycling is going to help, nor using re-usable shopping bags, or using electric cars or traveling by bicycle, because we over consume.
People think I'm green, and that I care about the environment, because I ride a bike rather than driving, I don't use plastic bags for my shopping, I re-use bags computers come packaging in as garbage bags, and generally have a low "carbon footprint" compared to others. But honestly - I'm not green, I'm just cheap. As it turns out, being cheap is quite green, and one can easily be mistaken for the other. I don't think nuclear power is a good idea, not because it's giving us all cancer (which it probably is), but because it's bloody expensive. Yes, once the plant is up and running, it's cheap. But how long does a plant last before it has to be "decommissioned", (or an uneducated night worker is left in charge and the whole thing explodes). Then you're left with a pile of reactive material that has to be disassembled by robots, and is ridiculously expensive to dispose of and contain.
I don't care about "the planet", not only because we're screwed anyway, but because I think we're going to kill our selves or something is going to kill us long before we "kill the planet". Biological war (or accident), nuclear war (or accident), a "big bang" or whatever killed the dinosaurs; I don't know - but I bet it'll happen.
We are very conceited (see comment about the sun revolving about Earth - we are the center of the universe). We think we have complete control. We build "earthquake proof" buildings and think we can control forest fires. We can't, which is fine - we just get proved wrong once in a while. Thinking we're smarter than nature is one thing, but we keep messing with it. Ever seen "Jurassic Park"? Or "The Core"?

I've definately gotten a bit off track.
Thinking too much does my head in. Best not to too often.