Sanity
Dib once looked up the definition of Sanity. It was something along the lines of the soundness of health with the body and mind. So, he would assume he was healthy, of course in both body and mind. So what if he believed in aliens. He was right and Zim was living proof of it.
But he wasn't satisfied with that answer. It was too broad. So on a whim, he decided to look of the term Insanity. It was obviously the opposite of sanity and if he fell into the category of Sane by the definition of sanity then surely he wouldn't fall into the category of insane as well. It just couldn't happen.
As luck would have it for him, he didn't actually believe he could be insane, even after he looked up the definition. Honestly! Really, he didn't. He wasn't repeating the same move, over and over, expecting to get the same results. All those rants and raves in class about Zim being an alien and 'why couldn't you see that!?' were just a warm ups.
He was going to come up with something big. Something different too. He could prove to the world he wasn't insane, by finally proving Zim was an alien. Tomorrow he would come up with a good way to expose Zim as an alien. Tonight, he was going to bed. Or rather, it was morning now, just really early. In a round about way it was night then.
Dib sighed and crawled into bed. The light automatically turned off when he laid his head down. He really needed to stop agruing with himself over silly things like day and night. All he needed to think about was how to stop Zim.