The fall is always the time for quiet contemplation at the museum or gallery, and this year, the city’s cultural institutions have some particularly note-worthy lineups, with an emphasis on some of the best American artists of the late-twentieth century.

At the Museum of Modern Art, “The Big Picture: Abstract Expressionist New York” is a survey of the best of AbEx, all drawn from the permanent collection. At the Metropolitan Museum of Art, “John Baldessari: Pure Beauty” showcases the Southern Californian conceptual artist, while Robert Rauschenberg gets a big survey show at Gagosian, and Jeff Koons’ 1991 controversial show is re-staged at Luxembourg & Dayan.