O n a perfect spring day in Paris, the deer is first visible in the distance, poised between an avenue of just-budding plane trees in the 7th arrondissement. Its head is raised, its body poised. Seen there among the trees, it really could be a wild animal. In reality, it is a concrete deer, and not even a particularly naturalistic one, since it has the distinct look of origami about it. The sculpture is a play of scale and weight, as if feather-light folded paper has been enlarged and transformed into heavy concrete. The deer is strapped to a flat-bed truck, and it is being driven into the grand modernist headquarters of Unesco, the UN agency that looks after heritage, culture and education. It will stand there for a day in its gardens, with Alexander Calder’s Spirale for company and the Eiffel Tower as a backdrop.…