"Carl is Such a Homophobe! I Bet He's Secretly Gay!"
If you watch any movie or television show that focuses on gay characters, particularly those made by Alan Ball, you're going to eventually see the "Hates Gays Because He's Secretly Gay" character (see American Beauty). It's such a pop culture archetype that in real life when you see some guy at the gym expressing disgust at the whole gay thing, you automatically assume he's got some pictures of well-oiled dudes under his bed. Or actual dudes.
And we do see it in real life; staunch conservative politicians wind up soliciting sex in public bathrooms and sending pornographic emails to underage male pages.
Why it is Bullshit:
OK, we admit this is sometimes true. There was even a popular study done in 1996 with 64 male college students, 35 of whom were homophobes (according to a survey they filled out gauging their attitudes on the subject). The researchers hooked a meter to their dongs (seriously) and had them watch lots of porn (yes, this happened--here's the damned link).
It was found that the majority of the homophobes would get at least a semi-boner while watching gay porn (where only about a quarter of the non-homophobes got aroused).
You can see right away what's odd about the numbers. All-told, nearly half of their total test subjects got at least semi-hard watching the gay porn. So... half the male population is secretly gay? That seems fairly unlikely.
So, what is it? That guys who volunteered for this test were simply more likely to lean that way? You do have to wonder how dedicated they were to the anti-gay cause if they agreed to have some wires plugged into their tackle box while they sat and watched a movie called Rear Admiral.
Or maybe this was just some very well-made gay porn. Or, maybe this whole thing is just ridiculously unscientific.
Ding! We think we have a winner!
Hell, the above study even notes that gay lust and anti-gay rage can both give you a boner. We've got a confusion boner right now!
The main problem is that nothing in science says that "homophobia" is even a thing. It's not listed among the actual phobias. It's more of a slang term that gets used in popular culture to describe a huge range of attitudes, from people who have strong moral objection to homosexuality due to religious beliefs or upbringing, to people who physically find homosexual sex disgusting, to people who brim with an inexplicable rage toward gays.
Combine them all and you find that about half of the population thinks homosexuality is morally wrong (with intolerance skewing higher among older respondents, obviously). There is just no scientific criteria for which of those people are suffering from "homophobia."
It sounds like we're splitting hairs, but it's a great example of the kind of problem people run into when they decide to play amateur psychologist and "diagnose" the people around them. Remember, the guy who's spouting a particularly venomous anti-gay diatribe may be covering up for his own confused homosexuality, and may deserve only your pity. But there's a very good chance that he's simply a dick.