When you comport yourself as Glenn Beck does, providing justifications of your behavior is a must. After all, if you're going to lob as many conspiratorial and racially divisive bombs as Beck does, it stands to reason that you better have a good reason.

Beck's is simple: He says it's all true. Every word. And how can we be sure it's all true? Also simple:

BECK: How exactly do you think I can stay on Rupert Murdoch's flagship -- how do you think I can actually stay on the air if I'm making stuff up? Just wholly making stuff up and lying about the most powerful man in the world. How? How does that happen? How?

This is a favorite argument of Beck's: If I were lying, then I couldn't stay on the air. But I'm still on the air, so I must not be lying.

It's a neat little piece of circular logic with a glaring and crippling deficiency -- it's based on the premise that spreading false information on the air automatically disqualifies one from appearing on the air. Beck insists that his continued presence in the media is proof of the veracity of his arguments. In reality, he's proved only one thing: That he's still on the air.

I, for example, could just as easily say that my coffee mug protects me against Ebola infections, and since my organs haven't liquefied yet, it must be doing its job. I've not demonstrated that my coffee mug has special anti-viral properties, but I'm asking you to believe that it does based solely on the fact that I'm not currently suffering from hemorrhagic fever, which can be attributed to a multitude of factors (my coffee mug being among the least plausible).

Of course, the inherent logical weakness of the argument is only amplified by the fact that spreading misinformation on Fox News is less a fireable offense than it is a job description.