Bulgarian Christo Javacheff is one of the most controversial living artists. He's famed for wrapping up some of the world's most famous landmarks in a variety of fabrics. These include the coastline of Sydney, the Pont Neuf in Paris, park pathways in Kansas City, islands in Biscayne Bay, Florida and the Reichstag in Berlin.

Christo was brought up in Communist Bulgaria where people were not encouraged to see beyond how things look. Questioning was not encouraged. As a form of subversion to this, Christo believes he can reveal more by covering up objects, effectively blotting out details in order to more fully grasp the entirety.

Christo has been working in collaboration with his wife Jeanne-Claude since 1961.

The monument featured here is in Piazza Scala in Milan.

Leonardo da Vinci was a great painter, sculptor, architect, musician, engineer and scientist who lived 500 years ago. He first worked out how blood went round the body, and why the sky is blue. He made the first drawings of a helicopter and created the world's most famous painting, the Mona Lisa.

Would such a brilliant mind like his thrive today? Or would he be made to choose between being an artist, a scientist or an engineer? Society often likes to categorise people but this can be limiting. In a sustainable world people could explore their many interests freely, and society would benefit from this release of human potential.

This artist is famous for covering up well-known monuments. He believes that covering something up helps you to see the whole. Sustainable development also resists isolated causes, looking instead at how they are connected to the bigger picture.

The other day I was walking through the town when I came to that square where the big statue is. I noticed straight away that the statue had been all wrapped up in this huge sheet of black tarpaulin.

It looked odd, all covered up like that, but the really odd thing was: I couldn't remember who it was, the statue I mean, and I walk past it everyday, so I ought to know.

A few people had gathered round the covered up statue; they were watching a man from the council, he was busy checking that the tarpaulin was properly secured.

Then one of these onlookers, a funny little man with a funny little grin and a voice so loud it belied his short stature, he suddenly pipes up, "what's under your sack, Jack?" Now, the man from the council was obviously busy, and clearly felt he had no time to be answering questions from little men, no matter how funny they might or might not be. And so, he ignored the funny little man. He probably had a low tolerance level where funny little men were concerned. Oh, and by the way, I don't believe his name was Jack at all.

But the funny little man was nothing if not persistent. He was obviously determined to play, whether the man from the council wanted to or not, and he called out again, and this time, in an even louder voice, "What's under your sack, Jack?" Some of the onlookers began to laugh.

Perhaps it was this laughing that persuaded the man from the council to stop ignoring the funny little man. He sighed, heavily, "it's a statue of the Great Leonardo," he said.

And I thought, of course it is, it's Leonardo Da Vinci!

"Is it?" said the funny little man "and who's the Great Leonardo when he's at home then?"

"Leonardo Da Vinci," the man from the council said, and he turned away as though that was that, and he could finally get on with his job, and forget all about funny little men with funny little grins and unfeasibly loud voices. It wasn't to be, "Never heard of him!" said the funny little man."

The man from the council was visibly appalled that anyone could not at least have heard of Leonardo Da Vinci. So before he had time to think better of it, he was opening his mouth again - "You've never even heard of Leonardo Da Vinci?

"No, I have no knowledge of the gentleman at all," said the funny little man. "But you must have," exclaimed the man from the council, "he's one the most famous artists ever! He's one of THE most famous artists of ALL time!"

"No, never heard of him, " said the funny little man, as though it was no big deal. It obviously was a very big deal indeed to the man from the council, "But he personifies the spirit of the whole Renaissance, not only did he paint brilliantly, he was also a sculptor, an architect, a designer, a scientist, an anatomist. He made discovery after discovery. His ideas were years ahead of his time. Leonardo Da Vinci was a hero, some people would have liked to have seen him burnt at the stake, and all because he wanted to advance the understanding of science and the world, he - "

And that was when the funny little man suddenly interrupted the man from the council, and said, "That's a bit like today, when you get them scientists and philosopher types who want a sensible debate about stuff like genetically modified food, nuclear power, human embryo research, cloning, and that kind of malarkey, and some people get really, really furious when these things are even mentioned and think such talk should be banned forever. It's like that, isn't it?"

The man from the council stared at the funny little man in total astonishment, his mouth was wide open, "well, yes, it's exactly like that," he said, quietly. "So that's Leonardo Da Vinci then is it?" the funny little man asked and grinning even more bigly than ever. "Yes," said the man from the council "Right, well if that's Leonardo Da Vinci, fair play, he definitely deserves a statue he does. Anyway, I can't hang around chatting to you all day, you know, things to do and all that, so if you don't mind, I'll be running along, no, I really must go, see you!" And the funny little man with the funny little grin and the voice so loud it belied his short stature, he walked away quickly and was never heard of again, until the next time.

I can't believe that I didn't know that the statue was a statue of Leonardo Da Vinci. It's funny how sometimes the best way to draw attention to something is to cover it up; and it's funny how sometimes the best way to hide something is to reveal it completely… funny, and a little bit worrying too.