Circa III: Soleri's arcologies: In Arizona, a visionary architect has decreed a stately pleasure-dome - The concept is a metropolis in miniature

Best-known, most publicized, and least built of radical new city concepts are the "arcologies" of Paolo Soleri, an Italian-born and -trained architect who has made his home for many years outside Scottsdale, Ariz. An arcology - a word coined by Soleri, connoting architecture plus ecology - is a self-contained, morphologically various, three-dimensional structure that constitutes a whole living city in itself. Although some people may regard Soleri's designs as megastructures, he is careful to remind us that they are really a form of miniaturization of cities, in which functional interactions are highly integrated. Thus arcologies embody ideas far more soaring than the primordial housing and city functioning that most megastructure or merely monumental concepts suggest. Arcologies are lit by a visual imagination whose only match in words (for my money) appears in Invisible Cities, a poetic novel by the Italian writer Italo Calvino, or in Anabasis by St. John Perse.