What is a monster? Ask a child and they might point to pictures of a dragon or the boogeyman. But my favourite definition is that monsters are fear. 

Modern use of cute monsters like My Pet Monster or Monsters Inc is a way to reduce the power of fear.  By making something scary look funny its power is reduced much in the same way as the public speaking advice about imagining the audience all naked.  This is particularly apparent in those most susceptable to fear, children.  Without fail if there is a typical childhood fear then there is a funny saying, story or toy about it. Jerry Seinfeld has a good quote about fear but here I will refer to Steven Colbert's words "You can’t laugh and be afraid at the same time—of anything. If you're laughing, I defy you to be afraid."

Monsters were used for centuries to explain the unknown.  It is regularly said that fear and ignorance go hand in hand.  As science has pushed the curtains of our minds further back so has it pushed monsters back into the corners of our understanding. Where do we see monsters now? When we sleep. Sleep is an topic of medical science that I think we are still very ignorant about. Who do we often call monsters in the public eye? People with physical and mental disabilities. Often simply from prejudice. Martin Luther King and many others have drawn on the union of fear, ignorance and prejudice.

Monsters are so tied to such strong negative connotations that to call something a monster is one of the worst things someone can say.  It is practically impossible with our understanding of modern biology to call an animal a monster and when they are it is usually because they have taken on aspects of a human trainer.  Some recipiants considered deserving of the title of monster are people such a morally corrupt or violent criminals.  The whole topic of men and monsters has been explored famously in Dr Jekl and Mr Hyde, Frankenstein, The Picture of Dorian Grey, Scarface, and the list goes on for quite a while. It's quite a favoured topic for artists. I think this is in part because of the greyness of the definition and the murkiness of the path to get there.

Monsters. Why do they exist? What are they? How do you become one? Traditionally the dragon was slain by the noble knight and I will argue that in the modern day not much has changed.  Monsters still exist, most commonly in people's minds, in my mind even.  How do you 'slay' them?  The best answer I have been able to find is by acting like a noble knight; couragous, moral, tough, dutiful.  In seeking to be able to conquer monsters, be knights, people (not just batman :)) are told to face their fears and "Always do what you are afraid to do."