...which are essentially the same pet peeve, in, y'know, different contexts.
1) Smoking doesn't cause cancer, because I smoke and I don't have cancer!
You've got an argument? Fine. Bring it on. This isn't an argument, it's a fucking rationalization. You've smoked a pack a day since you were thirteen, and you're in perfect health? That doesn't mean that there's no link, it means that you were fucking *lucky*. It's like saying "I got shot and didn't die, therefore bullets don't kill people." What the hell kind of science is that? You can't map a trend from a sample of *one*.
2) Global warming is a hoax, because it's a cold day outside!
...and let's also add the left-wing "How can people say global warming is a hoax? It's such a hot day outside!" Yes, I've heard both.
Now, look. I'm a global warming skeptic. There's an argument to be had here. This is not it. Climatology means mapping trends over periods of thousands of years; you've gone ahead and made an assertion based on a study of *twenty seconds*. In one location. All argument like this does is serve to make the rest of us look stupid.
(Insert snarky "You don't need any help for that! Ha-ha!" here.)