The idea of art is everywhere these days. I turn on CSPAN and there is John Updike, lecturing at the National Institute of Humanities on American painting. He divides, with flinty irritability, our painting history into "lineiness" (horrible word!) and "painterliness." Updike ridicules John Singleton Copley’s startling and surreal portrait of Nathaniel Allen (1763) for its heightened artifice and then rips into Charles Sheeler and Thomas Hart Benton.