For as long as critical analysis of comic books as a medium has existed, there have been existential questions about the Batman. Readers and critics alike have studied this pillar of the DC Comics universe for decades. But while questions about some of DC's other heroes - Superman, Wonder Woman and the rest of the Justice League - tend to have easy answers, the Dark Knight is a more difficult puzzle to solve.

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Countless writers and artists have contributed to readers' continued and never-ending analysis of Gotham City's Caped Crusader. And while no one has really inched any closer to answers about what truly makes Batman tick, the stories that raise the questions have enthralled fans for generations.

10 Is Batman A Product Of Nurture Or Nature?

Superman: Speeding Bullets By J.M. DeMatteis, Eduardo Barreto And Les Dorscheid

Kal-El as Batman in Superman Speeding Bullets

While a Superman story, the Elseworlds one-shot Superman: Speeding Bullets raises some questions about Batman. It follows an Earth where Kal-El's capsule was discovered by the Waynes. They adopt the child within as their son Bruce, who grows up following his parents' murder and becomes the Batman.

By the end of the story - thanks to Lois Lane - Bruce discards Batman and his brutal methods in favor of adopting the hopeful mantle of Superman. The story's thesis is that altruism and heroism are part of Kal-El's inherent make-up. Without intending to, the story - an Elseworlds tale that goes too far in some places - questions whether Bruce Wayne is destined to become Batman, regardless of his circumstances.

9 Why Does Batman Persevere?

Batman: The Cult #1-4 By Jim Starlin, Bernie Wrightson, Bill Wray And John Costanza

Batman is pushed to his limits in "The Cult."

There have been several stories throughout Batman's long history that examining the limits of the Dark Knight's stamina. Most focus on Batman's physicality, but no story has placed so much mental weight on the Caped Crusader as Batman: The Cult.

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Pitted against a religious cult led by Deacon Blackfire, Batman is captured, beaten and tortured in gruesome fashion, making readers wince along with every ounce of pressure applied to their hero. Eventually, readers are led to question what fuels Batman's internal drive to persevere in the face of ceaseless, nightly attacks and tortures?

8 Is Batman The Sum Of His Experiences?

Batman (Vol. 1) #700 By Grant Morrison And Various Artists

Time and the Batman

Examining Batman through the lens of the metaphysical has been one of the great passions of writer Grant Morrison, one of Batman's all-time greatest writers. With "Time and the Batman" from Batman (Vol. 1) #700, Morrison reaches the zenith of their examinations. Studying Batman's past, present and future, Morrison summons elements from Batman's history, as they did through their entire run as the character's head writer.

Elements ranging from Bat-Mite to the Batman of Zurr-En-Arrh and everything in between were subject to Morrison's exploitation during their run. Are the pre-Crisis events of Batman's life truly part of the canon? Should they be considered in the totality of Batman's existence? And, as is the ultimate question when Morrison goes meta, does it matter?

7 Does The World Have A Place For Batman?

Batman: Last Knight On Earth #1-3 By Scott Snyder, Greg Capullo, Jonathan Glapion, FCO Pascencia And Tom Napolitano

Batman emerges in Batman: Last Knight On Earth

For the modern standard in thought-provoking Batman stories and imagery, readers need look no further than the classic collaboration between writer Scott Snyder and Greg Capullo. Batman: Last Knight on Earth features a world where the citizens of Earth have all but abandoned the very notion of heroism and have turned to DC's most diabolical villains as the recipients of their admiration.

It's a world where Gotham City is slowly becoming unrecognizable to the Dark Knight. And despite Snyder's wild scenarios and Capullo's inventive visuals, one question sits at the heart of the entire enterprise: Has the world moved beyond Batman?

6 What Are The Limits Of Batman's Moral Code?

Batman (Vol. 1) #237 By Dennis O'Neil & Bernie Wright & Harlan Ellison, Neal Adams, Dick Giordano And John Costanza

Batman interrogates a Nazi war criminal in "Night of the Reaper!"

Batman's one rule has been well-established through the decades: the Dark Knight does not take lives. However, the true morality of that personal directive was put to the test in the 70s as part the attempts of writer Dennis O'Neal and artist Neal Adams to revitalize the character.

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With a pair of Nazi war criminals on the loose in Gotham on Halloween night, Batman finds himself racing against a vigilante known as the Reaper. The Reaper is bent on killing the former Nazi agents. Of course, in Batman's eyes, no one has the right to take a life. But that view is challenged when the Reaper is revealed to be Dr. Benjamin Gruener - a Holocaust survivor.

5 How Compassionate Is Batman Willing To Be?

Batman: The Killing Joke By Alan Moore, Brian Bolland, John Higgins And Richard Starkings

Joker loses his mind in The Killing Joke.

Alan Moore's The Killing Joke remains arguably the greatest story featuring Batman's archenemy and one of DC's most skilled manipulators. The Joker attempts to torture Commissioner Gordon to a breaking point by paralyzing Barbara Gordon and subjecting Gotham's top cop to an amusement park ride of terror. And it's all in the service of proving that a single bad day can break anyone.

In the end, Batman actually offers to help the Joker. While the Clown Prince of Crime considers the offer, he ultimately turns the Dark Knight down. And Batman questions if he sees an endgame for his tumultuous rivalries with his rogue's gallery that doesn't involve bloodshed.

4 Is Bruce Wayne Or Batman The True Identity?

Batman: Ego By Darwyn Cooke, Jon Babcock And Mark Chiarello

Batman confronts his own id and ego in Batman: Ego.

Batman is faced with a battle taking place literally within himself. After a petty crook named Buster Snibbs gives up the Joker's location to Batman, Snibbs can see the writing on the wall. He takes out his own family before taking his own life, anticipating the Joker's retaliation.

Consumed by guilt, Batman's mind splits into two halves: the revenge-driven Batman and his "real" self, Bruce Wayne. Whether Bruce Wayne or Batman is the mask is a question that's been posed before, but Cooke's Batman: Ego brings it to the forefront in a way readers had never quite seen before.

3 Is Duality Holding Batman Together?

Batman: Legends Of The Dark Knight (Vol. 1) #28-30 By Matt Wagner, Steve Oliff And Willie Schubert

Batman Faces Cover By Matt Wagner With Batman And Harvey Dent Two-Face

There is no better mechanism for studying Batman's duality than a good Two-Face story. And "Faces" from Batman: Legends of the Dark Knight (Vol. 1) #28-30 is one of the best. After a two-year absence after another escape from Arkham, Two-Face embarks on a killing spree. Batman investigates the former Harvey Dent's attempts to acquire a secluded island as well as recruiting an army of circus sideshow performers.

It's a fascinating story that examines the reason that everyone wears two faces: One in private and one for the public. It's a common thread among many of the Dark Knight's foes. Batman lives that very dichotomy, and at the end of the story, writer and artist Matt Wagner ponder whether his broken identity is what keeps Batman together.

2 Who Is Holiday?

Batman: The Long Halloween By Jeph Loeb, Tim Sale, Gregory Wright And Richard Starkings & Comicraft

Batman In The Long Halloween

Sometimes the simplest questions are the most fun. Batman: The Long Halloween sees a mysterious killer called Holiday claiming a new victim on every major holiday, starting on Halloween night. There aren't any burning questions about the dual nature of Batman or deep pondering about the human condition.

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But it is an excellent whodunit, with writer Jeph Loeb planting red herrings throughout and keeping the audience guessing. It isn't thought-provoking in the way other entries on this list are, but like any good mystery, readers have to maintain a sharp mind to keep up.

1 Should Batman Be Locked Up With His Enemies?

Batman: Arkham Asylum By Grant Morrison, Dave McKean, And Gaspar Saladino

DC Comics' Batman Arkham Asylum Cover, depicting Batman walking into Arkham

Grant Morrison and Dave McKean collaborated to produce Arkham Asylum: A Serious House On Serious Earth, the definitive tale of Batman facing his entire rogue's gallery in a single night. The inmates are literally running the asylum, and Batman has one hour to stop them all before all hell breaks loose.

As he descends further through the asylum and confronts one enemy after another, his understanding of what he calls "madness" begins to change. Until, near the end, it's clear to him that his own mental state might warrant his own cell in Arkham.

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