Great minds have struggled for centuries over one of the fundamental cultural questions: What is art?
Following in the footsteps of thinkers such as Immanuel Kant and Leo Tolstoy, a Brighton and Hove Council cleaning crew decided to make a small contribution to the debate.
When they came across a slogan painted on an art gallery window, they made a quick assessment of its aesthetic value - and decided it could only be the work of vandals.
They set to work removing the phrase Portslade Massif from the Ink_d gallery in North Road, Brighton, after they decided the reference to ghetto-style gang warfare on the west side of Hove proved it was just another piece of illegal graffiti.
Unfortunately, like many critics before them, they had mistaken a piece of modern art for a talentless daub.
In fact, the slogan was part of the title of an exhibition by controversial musician and artist James Cauty, whose works were on sale inside the gallery for more than £4,000.
Gallery staff were nonplussed when they arrived on Friday morning to find the sign on their window had been removed.
Dan Hipkin, Ink_d studio director, said: "Brighton and Hove City Council, like anywhere, has problems with graffiti gangs but this is private property and my problems with the cleaning crew doing this is more about freedom of expression.
"If it was so offensive, then why weren't the police called?
"If we'd written the words in neat writing they wouldn't have touched it.
"They obviously thought they were helping but they weren't."
A spokeswoman for Brighton and Hove City Council said: "We apologise for removing the writing from the window of the art gallery.
"It was a genuine mistake, one among the many successful and careful removals of graffiti that the council cleans off private properties every year.
"In this case, we responded as soon as we were aware of what had happened.
"Our advice would be to check with the council first when painting messages on private buildings as it may also be breaking planning regulations.
"Having said that, our graffiti team will be more cautious in the future."
Mr Cauty held a sale of the art on show on Thursday night exclusively for the people of Portslade.
He hit the headlines as the frontman of alternative early- Nineties chart-topping duo The KLF, who as The K Foundation infamously burned a million pounds in banknotes.
He created the works for his exhibition, The Rize and Fall of the Portslade Massif, while living in the area for the past four years.