In my quest to seek out the grandest narrative of my limited conscience, I have come across several candidates. From the linguistic masterpieces of J.R.R. Tolkien's Middle Earth epics, to the lyrical narration of Elaine Cunningham's Book of Song and Swords, and even to the philosophical scriptures of Chris Avellone's Planescape: Torment, these narratives of heroism, human nature and other musings have influenced the way I look at the world. Each story dabbles on many aspects of the psyche, some indirectly, some otherwise.
But the musings that interest me the most perhaps are the concepts of insanity and madness. While Avellone's Torment does touch on the subject given the nature of the world's setting, none have been as riveting or enticing as H.P. Lovecraft's Chtulhu Mythos. Admittedly, the works I've read and seen are somewhat limited, however, from what I've touched on so far, the Mythos has a way of stimulating the imagination, allowing an amalgam of horror, wonder and introspection. Lovecraft's work has spread throughout many aspiring authors, most notable of which is critically acclaimed novelist Neil Gaiman (still finishing his version of Sherlocke Holmes, with a Chtulhuian twist).
Of course, discussions of madness and bat shiat craziness should never be made without pointing out the works of Frank Miller (and it has nothing to do with the line in the 300 movie, so no, this. is. not. SPAAARTAAA!) Most notable of this is Miller's attempt of portraying the Dark Knight, otherwise known as the goddamn Batman. In his continuity, Miller portrays Bruce Wayne as a vigilante who is just as insane as the criminals that he hunts. Of all the Goddamn Batman books that have taken my curiosity hostage(surprisingly, not by Frank Miller), the Killing Joke by the incomparable Allan Moore is on top of the list. I've personally seen the Batman character as evolving lesson of psychology, between Batman's cold and calculating personality that puts him on par with more powerful heroes such as the dick that is Superman, and the villains that he fights, most notably, the brilliantly barmy Joker, each character represents a deeper understanding of the faults and bizarreness of the human mind.
These two examples of modern literary masterpieces, in my humble opinion, are more relevant than any text book of science. While I do not advocate the abandonment of reading the works of long dead Caucasian men otherwise known as philosophers or psychologists (they have their value), these pieces of art, originally designed to entertain iterates that concepts of the inner bowels of the ever complexity of our gray matter. The mere fact that we, as sentient beings are capable of both rational and irrational ideologies and actions should tell us that madness, indeed, is present in all of us. It may manifest it's symptoms differently from person to person, and in varying degrees. But there is no denying that it is a shadow that echoes in every thought and action.
After all, we're all a little bit crazy. And nothing tells you that better than popular media. The choice now is whether you accept or live in fairy tale of delusive sanity.