As children, we have all suspected it: perhaps we are all, moving strangely beneath the sky, victims of a trap, a joke whose secret we will one day know. This reaction is certainly infantile and we turn away from it, living in a world imposed on us as though it were “perfectly natural”, quite different from the one that used to exasperate us. As children, we did not know if we were going to laugh or cry but, as adults, we “possess” this world, we make endless use of it, it is made of intelligible and utilisable objects. It is made of earth, stone, wood, plants, animals. We work the earth, we build houses, we eat bread and wine. We have forgotten, out of habit, our childish apprehensions. In a word, we have ceased to mistrust ourselves. Only a few of us, amid the great fabrications of society, hang on to our really childish reactions, still wonder naively what we are doing on the earth and what sort of joke is being played on us. We want to decipher skies and paintings, go behind these starry backgrounds or these painted canvases and, like kids trying to find a gap in a fence, try to look through the cracks in the world.