Sometimes good ideas sound good at the start and then when you're doing them or have done them, crash back down to Earth. In 2004, when Banksy-fever was high, yet his renown in the art-world only a sliver of what it is now, the artist produced a performative piece of art that was part stunt and part installation. It was conceptual, but also a bit of a laugh.

Printing out roughly £1million worth of fake £10 banknotes, Banksy took to handing them out at festivals and throwing them off of buildings. It then struck him. Shit, this is forgery and I could get in big trouble. Huge murals and installations already placed some value on his head and a counterfeiting charge was hardly going to help.

Tom Hockenhull is the curator of modern money at the British Museum and was keen on getting one of these skit-notes to add to their burgeoning collection. His issue wasn't so much their legality though, rather their authenticity. Since Banksy had recalled them, or at least put a stop to their production, other people began to reproduce them with photocopies. It was a kind of 'We Are Banksy' moment a la V For Vendetta.

Although this is his first official piece in the museum, it's not his first to appear there overall. In 2005 he stuck Peckham Rock to the walls, blending in as another piece of prehistoric art. The faux-primitive cave painting depicted a man pushing a shopping trolley with a tongue-in-cheek descriptor of the piece to accompany it. Now with the Diana note, the question is less about the merit of art daubed on walls and more about the value money carries, considering it is essentially just a piece of paper.

That's to oversimplify it of course, it's a symbolic piece of paper that denotes an agreed upon exchange. Still, the mischief, humour and reputation behind its creation has turned it into a sought-after piece. Artworks like these have all but solidified his reputation as the art-world's pre-eminent trouble-maker. A rebel very much with a cause. In a mythological parallel, he's a contemporary Loki.

In Norse mythology, Loki is the God of Mischief. He's a cunning trickster with a good heart. Banksy's public persona is very much in the Loki mould. Yes, he's anti-authority and yes, he holds power under suspicion, but the evangelising intentions are always good. His work has been, for many people, the onus for lifting the blinkers off. He has revealed that not all is what it seems and that simple acts are capable of affecting great change.

Loki is the son of Odin, the God of Wisdom. Banksy, although anonymous (so we don't know his parents, God or otherwise), acts out of a reverence for wisdom. With simple images, predominantly stencils, his wisdom is distilled into art that is effective and easy to interpret. It's aesthetically pleasing with a bit substance. Loki is also the 'slighted' brother of the preferred Thor. This too is a crucial aspect of Banksy's persona. No matter how much of an establishment figure he has become, the outsider status of an artist raging against the machine must still endure. Otherwise, the statements in the art lose value.

Considered an INFJ personality type, the Loki character helps us to understand Banksy. The 'I' in INTJ is Introverted Intuition and relates to Loki being a loner, working in secrecy to devise plots that are acted out more publicly. An INFJ is capable of being two people. There's a public and private. The melancholic and the humorous. These dualities may exist in everyone, but are magnified in this personality type. Banksy, in his relationship to the British Museum embodies this.

Poking fun at banks, money and our sense of value, his notes, partly through how they looked and partly through how they were disseminated, have gone on to become valuable objects. His cave painting was well thought-through, no detail was overlooked, especially in the execution of the transition between private thought and public display.

Defining Banksy or his work isn't easy, but seeing the mechanisms at play helps. It means that some things are certain. His work will continue to surprise, operating both on a cerebral and physical plane. These two qualities combined should continue to intrigue the art-world as he walks a tightrope between anti and symbol of establishment.