Can graffiti ever be valid, given that the word is defined as, “Possessing legal authority; executed with the proper formalities; legally acceptable or binding.” (OED) or should we accept that works by the likes of graffiti artist Banksy become valid, over time, due to an appreciation of the quality of the work and a subsequent acceptance, by both the general public and local authorities. The case of the removal of Banksy’s Slave Labour and No Ball Games murals from walls in north London is a case in point, where both locals and some councillors strongly objected to their removal by the owners of said walls for sale here and in the United States.

Perhaps the same case of validity can be made for modern stone circles – ie it is the ‘quality’ that matters not the ‘validity’ (though please don’t ask me to define quality :-)