In one of the many conversations that animate "Columbus," a serenely intelligent first feature from the Korean American writer-director Kogonada, a part-time librarian named Casey (Haley Lu Richardson) and her co-worker Gabriel (Rory Culkin) discuss a tricky double standard. As Gabriel notes, someone who loves video games but finds books boring is criticized for having a short attention span, while someone with the opposite inclination is praised for having a long one. "It's not a matter of attention span, but of interest," he says. "Are we losing interest in things that matter?" Mercifully, he does not go on to extol the importance of gentle, gorgeously contemplative independent films like this one, though by that point "Columbus" has already made the case in much more delicate and persuasive terms.