Sandro del Prete

One day, an artist drew an illustration of a dancer on a sheet of paper. To enhance the effect, the sheet was rolled up, but it always returned to its original shape. Noticing this, the artist drew a hand at the at the other end and on the opposite side of the sheet of paper, so as to prop up the dancer. He then hung the sheet on the wall and stepped back to judge the effect. Suddenly, the hand disappeared: in its place appeared a second dancer. When he approached the illustration, the hand reappeared. Meanwhile, the second dancer, perhaps wishing to be a bit more "real" then her counterpart, had slipped her feet through the bottom of the rolled sheet of paper.