What do the cats and humans symbolize in The Garden of Stubborn Cats by Italo Calvino?

The cats symbolize the natural world. They inhabit a world in which humans have long forsaken. It is a world still filled with mystery and life. It is connected with the natural world (the old lady's garden), a hidden oasis amidst the concrete jungle that man has created. Man's world is a dead world. Man has forsaken nature and the mystery of life for motorcars and freeways.