Ernest Pignon-Ernest's visual artwork is seen in the streets of many towns: Naples,South Africa, Lyon and Paris have all hosted installations. A pioneer in urban art in France, he produces screen prints, drawings on black stone, paintings that he sticks to walls, doors, or stairs, and that work with the architecture.

When someone creates an image, he shows others, then he shows himself. The artist isn't there, but at the same time he is. The fact that they create the image is a kind of birth of the artist. It's like he's signalling to you via the art: asserting himself as a subject, which means he makes an image within a community and for others. He says, "I am a man". It's like waving a hand, a hand signal.

People in the Palaeolithic made sure their images were born from the rocks themselves:  they used the tiniest fissure, the slightest curve in the rock… as if the animal was born from that rock, like the potential was already there. Or sometimes – like the horse at the end – you get the impression the animals are emerging from the depths. This idea is there all the time. In that way, the sacred is there inside.

The strongest and most disturbing thing is maybe even when there is no drawing. They have just scraped away the rock, and the rock becomes a mammoth: it's almost a sculpture. They're saying to us: "See, these animals are here, potentially, they're here".