Positive Existentialism is the belief, which I just made up, that humanity can never fully understand the universe, what with being contained within it and all. Futhermore, the belief that this is a Very Good Thing.
Frankly, the day humanity discovers the Ultimate Truth underlying Everything (Reality itself, not the website) is the day I give up on living and jump off a bridge. I've got nothing short of a phobia regarding truth. I like speculating as to what it might be as much as the next guy, but if I was walking along, musing to myself, contemplating existence, and God (the omnipotent being, not the e2 user (unless they're one and the same)) suddenly popped into existence right there in front of me, and spake, in a loud, booming voice, thusly: "You Understand Everything Now!", I'd become totally, completely, and ultimately fatally depressed. What's life without mystery?
Thankfully, Positive Existentialism nullifies this fear--after all, were God Himself to pop into existence in front of me and tell me I understood everything, I'd have plenty of reason to doubt him. How do I know He's God? How do I know He's not lying to me? For all I know, it's the nature of reality that a God-looking anomaly will pop into existance in front of any gullible sucker who muses too long about the nature of reality, and inform him, in a loud, booming voice that he understands everything.
As long as I admit that I can never hope to understand the universe from within the universe, I can't take anything I see at face value. Mystery therefore abounds--Everything (both Reality itself, and also the website) becomes mysterious.
That's what I'm talkin' about.