When we classify furniture as art, we do so because of an elevated design or an unusual poetics. But what about the mastery hidden beneath the cushions? “Deep Seated” offers viewers a look into the art of upholstery, specifically the laced-spring technique. The exhibition ranges widely, looking at furniture from the Renaissance, Baroque, Empire, and Art Nouveau periods to 20th-century modernism and contemporary experiments. Next time you plop yourself down on a couch, you will think about what’s beneath you. —Clara Molot