(Directory on Nihilism: https://www.philosocom.com/post/the-irony-of-nihilism)
The Joker is one of the most iconic fictional villains (originally from comic books). In some ways, he is more popular than Superman and, to a lesser extent, Batman.
In this article, I will try to explain the character's rationality, despite it being defined by insanity. After all, he wouldn't have been popular without both.
He is a very mysterious character with no definitive origin story or real name. Since the previous century, he has had various names and origins, but none of them are considered his "true" background. Only interpretations. This may include his own movie.
(There are also various versions of the Joker, but let's not digress.)
What makes him very unique is the fact that he has no ambitions and has no clear purpose or philosophy. He is probably fiction's most adored nihilist.
To describe it briefly, nihilism is essentially the rejection of all meaning. A true nihilist does not attribute meaning to anything, not even to themselves.
However, some nihilists may enforce their philosophy with logic, even though logic is meaningless.
This can make one a very dangerous individual; One that has no respect or tolerance for anything. The Joker is, basically, an agent of chaos. His "purpose" is to cause mayhem for mayhem's sake. Nothing more.
Despite being an extremely unstable man, the Joker always has clown makeup on. I think I understand why. He is a clown because he makes a mockery of society and humanity, out of our need to cling to purposefulness and value.
He does so by committing acts of terror and mischief, all to laugh at our existing order. Truly, he's the ultimate anarchist.
Friedrich Nietzsche saw his "Overman" as being one step above humans. His "Overman" is one that lives by their own rules, laconically.
The Joker's "philosophy" is one that does not even exist, and in a way, it is above Nietzsche's dream of moral independence. The Joker is one that is independent from morality itself.
He does not see a need for it. Unlike Nietzsche, who takes morality away from others, The Joker kidnaps said morality, ties it to an electric chair, and blows it up with TNT.
You might think that the Joker is a lunatic, but I think it's possible to understand his "rationality." I think his rationality comes from the notion that there is little point to reason, allegedly, when you can reject it all and just give in to your urges.
Logic is something that humans don't necessarily inherit. We are not necessarily logical beings by default. However, we can learn to be more logical through philosophy. Philosophy is the study of the fundamental nature of knowledge, reality, and existence. It can help us to understand the world around us and to make better decisions.
The Joker's "philosophy" can be defined as Chaotic Nihilism. Nihilism is the belief that there is no meaning or purpose to life. Chaotic Nihilism is a more extreme form of nihilism that rejects all forms of authority and order. The Joker does not believe in anything, not even himself. He is a creature of pure chaos.
Kefka (from Final Fantasy 6), a very similar character to the Joker, is also a nihilist. However, Kefka's nihilism is more depressing than the Joker's. Kefka believes that the world is a meaningless place and that there is no point in living. He wants to destroy the world and everything in it.
The Joker, on the other hand, does not believe that the world is meaningless. He believes that the world is full of possibilities, but that we are limited by our own beliefs and expectations. He wants to break free from these limitations and to live life to the fullest.
I think we can conclude this piece by saying that the Joker is an anti-philosopher. An anti-philosopher can be defined as someone who rejects any logic and any reason. Thus, in their absence, all that is left is unrepressed emotional behavior.
NOTE: I am not referring to the common definition of anti-philosophy that is defined by Wikipedia. According to Wikipedia, anti-philosophy is the rejection of traditional philosophy. (That version might as well be self-contradictory -- opposing something, using the same thing one opposes!).
The Joker's anti-philosophy is simply the rejection of logical reasoning as an important factor in our lives. Since morality and ideology also come from reason, they also get rejected by said character.
Final thoughts: I believe the Joker is a very relatable character nowadays because he embraces our complete submission to our whims.
By his actions, he calls to destroy the superego, or our repressing self, and give in to the id, the one that lacks rationality but grants plenty of gratification.
He is truly a.... comic relief.... in a world where we must restrain ourselves.
It seems that we humans do not like spending a lot of energy. Therefore, we may use plenty of shortcuts, to avoid exhaustion.
Perhaps one of them is to avoid improving our rationality? Maybe philosophizing is one of the reasons I am a very fatigued man?
Anyway, unlike the crazy clown over here, I haven't really had much fun in years. As someone who used to have a lot of fun 10–20 years ago, I think I understand his clinginess to infantile joy and poor humor.
He is a clown. And yet everyone takes him seriously. Even I. The irony.
(Even my cat is more reasonable than this guy.)