Thanks to B.L. Donnelly, Batman and related material have gotten a lot of mental airplay over here. Batman has strong roots in the Mystery Man pulps, not to mention Aristotlean philosophy (as often exemplified by Frank Miller's literature). However, I choose to examine the phenomenon of what allowed "Batman" to form as an idea and take the reins.
The canon of Batman's genesis goes as follows. Thomas Wayne, inheritor of the preposterously exhorbitant Wayne family fortune (money as superpower), goes to medical school and becomes a surgeon. Somewhere along the way, he falls for a powerfully idealistic woman named Martha. The two marry and have a son, named Bruce. Although often estranged from other youths and easily startled, Bruce had a good heart and a singularity for a brain. The family resided at Wayne Manor, which has a rich history. Set over a vast cave network, Bruce had his first encounter with live bats after tripping into a well. The event left him shaken, but otherwise unscathed. Most scribes put Bruce at around 7-10 years old when he and his parents set out to see Mask of Zorro on the big screen, as an endulgence for Bruce. This endulgence coincided with a very strong desire, or perhaps even need, for liquid assets in a gentleman named Joe Chill. Agitated by circumstance and possibly other stimulants (or lack of opiates), Joe Chill attempts to mug the Wayne family and in the scuffle shoots the parents before scrambling away from the devastated child.
Here's where the recounting gets shaky. The point at which Bruce re-encountered the bat shifts and changes often, implying a moment out of time. This is where I feel that Bruce interfaced with something much, much bigger than his individual consciousness, the moment in time that sent ripples through his short life. The well of bats didn't exist in Bob Kane's original story, instead coming from later authors. That said, it has been used repeatedly since its inception. Bruce was, nevertheless, left with nothing off of which he could project a Paternal or Maternal role directly, which left him open in that moment of trauma to recognize the Living Idea Being which he identified through the same sensation as a child trapped in a well with an endless stream of bats flying past him. Many authors have projected the idea of what he must have felt, yet it all seemed to ring strangely. It seemed clear-cut and softened, neglecting the raw uncertainty that comes from the loss of fundamental psychological rudders.
As with all great works, Batman started out in utter dreck. Bruce, understandably, felt responsible for the loss of his parents. He pleaded for hedonism's sake; he wanted to see one of his favorite action characters ride around on the big screen when he could experience the same from recording equipment at home. He wanted his mother to wear pearls to make the excursion a noteworthy event. If we take a step back and remember Bruce's exploratory and literate nature, he perhaps "remembered" sacrificial rites in Dionysian tradition, in which the vessel would receive the greatest accolades and endulgence before getting ripped to shreds. Seeing meaning in everything, this seemingly random event may have been part of a larger process of manifestation. If they hadn't gone out, and if he hadn't wanted to make a gaudy spectacle of it, his parents wouldn't have died. Bruce's sense of self-chastisement made any sense of enjoyment for its own sake something to be discarded. Bruce Wayne was responsible, so Bruce had to be cast out as the lead role. The child had such an aversion to the psyche responsible for the sacrifice of his parents on the altar of crime that he chose to embody everything that would send Bruce Wayne running: discipline, vigilance, and control. He chose the trauma in the well as his starting point. Considering Bruce Wayne as co-conspirator, he chose the very thing that would make the boy panic, and used it as his template for future endeavors. The Bat requires the absence of a commanding figure or figures before introducing itself. Bruce Wayne became the puppet, the unwanted thing that the controlling consciousness would use to avert people's attention to its doings. Despite continuing his Father's business and his Mother's philanthropic work, Bruce Wayne would do his best to come across as an idiot and dilettante, in order that the consciousness could return to lashing out at this vague "crime" thing of which Bruce was an unconscious part, using the spirit of the animal that brought the boy to quivering trauma. He would act as the vessel of the Bat.
I don't know how relevant, cohesive or sane any of this sounds, but I'm going to keep at it.
So, a man in a Bat costume runs around, ruthlessly mangling and mutilating those who would choose to bring pain to others through illegal means all throughout his city. Much of this, however, was beating the living shit out of drug addicts and other people whom life handed the short end of the stick. Chances are, Batman began in an ugly, ugly place. Just as it required the sacrifice of two outstanding people, the Bat-monster must have chewed on a lot of furniture and shat on a lot of carpets before the controlling consciousness could get a leash on it. Batman would now give rise to his antithesis, as if to create limits for himself. This he would manifest in the autocratic need for violence and justice in the Man, who would carelessly knock an externally unremarkable fellow into a vat of chemicals, out of which would arise The Joker.
Just as Batman became defined as Not Bruce, this Joker would become defined as Not Anonymous. Every act would be an indulgence. Everything would be seen as a source of amusement. The Joker has no alter ego, for his world is all for fun, and thus he has no need to act in shadow or in secret. The terrorization of the Bat-monster run rampant has consequences with the Joker. No one is an anonymous vessel for crime when a person chooses to become the opposite of their fears instead of the embodiment of them.
The Joker's inception perhaps initiated the Robin scenario as well. Seeing the effects of his works, Batman would perhaps see a unique opportunity in the newly orphaned Dick Grayson, already a child so different than the young Bruce Wayne of an equivalent age. The forgotten Little Boy Bruce found a peer, and Batman found a person in whom he could affect change without terrorizing. Although Robin and Joker share red and green elements in their appearance, Robin chooses yellow which complements the Joker's purple. From here, the Robin figure would act as the synthesis of Joker and Batman.
Grayson would eventually distance himself from Batman. Many authors have attempted to cover this disagreement, yet the result remains the same. He would take a new sobriquet not from the polarity of Batman and Joker, but instead from Superman's mythology, something foreign to the Matter of Gotham. The next Robin, Jason Todd, would not escape the polarity. Jason lacked the discipline that Grayson had learned as an acrobat, and had no desire to develop it. This would, inevitably, lead him to fall into the Joker's hands, or rather his repeated crowbar blows and explosives. Jason at first hung like a scarecrow, a bogeyman story to spook aspiring Robins. He would rise later as the consummate counterpoint, dressing in the rags and castoffs of others to attempt to put a name to his senseless rage. He would come to embody the self-loathing of young Bruce Wayne, the all-consuming sense of abandonment that would burn through whatever stupid outfit he'd put on. The third Robin, Tim Drake, was more of a mirror for Batman. Although he dressed in the colors of Robin, the vibrance and hyper-activity of Dick and Jason gave way to a predatory coolness and diamond-like intellect. Dick was the Detective personified, scouring for solutions to the mysteries that would present themselves before him. Unfortunately, Tim's emotional center hadn't the years of processing that Batman was afforded, and after his father's death, he would retreat into the indestructible mind of his for any and all trauma. When he sought initially to become the next Batman, the "death" of Bruce Wayne brought him to evolve the idea of what being Robin meant in and of itself, without connection to a Batman. Donning one of Jason Todd's Robin-derivative costumes, Tim would step out to solve the mystery of Bruce Wayne's death.
I think this is all I can do for now. There's a lot more to say on the matter, but the Mindless Ones have said it before and have said it better than I have. It's sometimes just nice to vomit information.