Nicholson Baker loves artificial constraints: the clarity they bring to a project, the odd angles and tones they inspire. The entirety of his first novel, The Mezzanine, takes place during a single escalator ride; his most recent work of nonfiction, Human Smoke, pieces together a history of World War II ­almost exclusively from snippets of contemporary accounts (newspapers, magazines, and diaries). So it was no surprise when Baker—sitting at his kitchen table, eating a tomato-and-cheese-and-cucumber sandwich—proposed a constraint for our interview. He asked—shyly, apologetically, but ­seriously—if we could somehow manage to conduct the ­entire thing without ever mentioning any of his books. Talking about them, he said, gives him a “cringe-y” feeling. That constraint, fortunately, turned out to be impossible. To talk about Baker’s life is, inevitably, to talk about his work; the membrane separating the two is unusually thin. If Baker is not exactly one of his own protagonists, he is a close cousin, or a fraternal twin. He and they inhabit the same world—one of odd enthusiasms (Wikipedia, singing poems), microscopically observed mechanisms (pencil sharpeners, windshield wipers), onomatopoeic noises (clonk, kashoonk), and quotidian anthropology (few other authors would notice, as Baker did in The Mezzanine, that late-twentieth-century American men trying to pass through a door at the same time always say “oop” to each other instead of “oops”). Occasionally during our conversations, Baker would recall a specific memory from his childhood—say, the pleasure of listening to music through headphones in the dark—and end up describing, exactly, a scene he’d already described as the childhood memory of one of his characters. Baker’s thirteen books divide roughly into three disparate categories: slim novels filled with idle thoughts about the trivia of daily life (The Mezzanine, Room Temperature, A Box of Matches); nonfictional polemics (Double Fold, Human Smoke); and wild sex fantasies (Vox, The Fermata, and, most recently, House of Holes). The books that don’t fit into those categories often manage to combine them. Checkpoint, a novel-in-dialogue about a man who wants to assassinate the president, is a wild polemical fantasy. In The Anthologist, a novel about a poet struggling to write the introduction to a poetry anthology, the trivia of daily life competes with a polemic for the hero’s attention and our own. After some twenty-five years of writing, Baker’s reputation is as unusual as his work. He has been praised, widely and enthusiastically, for his style, humor, originality, and empathy. (As Martin Amis once put it, “Throughout his corpus there is barely an ordinary sentence or an ungenerous thought.”) At the same time, some critics have very publicly loathed a handful of his books, most vociferously Vox (“tedious”), The Fermata (“repellent”), Checkpoint (“scummy”), and Human Smoke (“childish”). Many of Baker’s talents are self-consciously small: meticulously inventive phrasemaking, a masterfully intimate tone, and a superhuman gift for observation. He has a Dutch-painterly reverence for everyday rituals and objects—a belief that they will start to glow with significance if we only pay close enough attention. This has left Baker open to the charge that the work itself is trivial, quaint—a bubble of old-fashioned belletrism floating through a harsh ­modern world. (Leon Wieseltier, writing in The New York Times, once called Baker’s novels “creepy hermeneutical toys.”) What’s disguised by Baker’s cheerful tone, however, is his passionately sustained conviction that we should honor the details of our lives rather than getting carried away by projections and abstractions. In this quest, Baker has seemed continually willing to risk puzzling his fans and inflaming critics; he has shown an indifference to publishing fashions that few authors could have sustained. One index of this independence is that, although Baker has been published for his entire career in magazines such as The New Yorker and The Atlantic, he has never held a staff position. “I felt I had to be someone who would leap in from outside,” he told me, “and do some nutty thing and then run away cackling.” Baker is fifty-four years old, but you can still see the teenager in him: he is self-consciously tall and shy, and his face turned red, often, when we talked about his books. He lives in a rambling eighteenth-century house on the border of Maine and New Hampshire. We spoke there for several hours, first in the kitchen and then in the living room, next to the fireplace in front of which he wrote A Box of Matches. Later, Baker drove me to a restaurant in Portsmouth, New Hampshire, where, as we entered, a man exiting at the same time very distinctly said, “Oop!”