 Bernini's "David" is a three-dimensional work that needs space around it and challenges the viewer to walk around it, in order to contemplate its changing nature depending on the angle from which it is seen.The sculpture relates to an unseen entity – in the form of Goliath, the object of David's aggression – as well as to the spectator, caught in the middle of the conflict.The warrior even literally oversteps the boundaries between life and art, putting his toes over the edge of the plinth.