Early in his career, James Wood, the commanding, occasionally contentious literary critic at The New Yorker — once anointed “the last critic” — used a pseudonym. He published serious pieces under his own name, but his “hackwork,” as he has called it — short, 50-word reviews churned out for money — were the work of one Douglas Graham (Wood’s two middle names).

I thought often of Douglas Graham while reading “Serious Noticing,” a new collection of Wood’s writing. Two voices vie in this book. There is the voice we recognize in the reviews: the professor, stately and composed, guiding the reader through forensically close readings of the text, pointing out fiction’s innovations and revolutions — the “failed privacies” of Chekhov’s characters, the “unwrapped” consciousness in Virginia Woolf’s novels. The other voice — pitched about half an octave higher, blunt, reedy, very winning — pops up in the essays. I began to think of it as belonging to Douglas Graham, pragmatic Graham, who once paid the bills and still gives it to us straight.

The reviews and essays settle into a rolling rhythm, pleasing counterpoints. In the criticism, Wood stands at the front of the classroom, extolling that “serious noticing,” an attentiveness to language and the world that can serve as a small stay against oblivion. In the essays, Graham unravels all such certainties, lightly trolling: How absurd that I’m paid to do this work! How long will the money last? Wood luxuriates in D.H. Lawrence’s “joyously messy” sentences. Graham upbraids himself for being such a good boy, and for never daring to write such sentences himself. Wood is haunted by fiction and its effects; two reviews in the collection, written 20 years apart, analyze the same short story, Chekhov’s “The Kiss.” Graham, meanwhile, daydreams about giving his books away. Wood contemplates the death of God; Graham, the overdose of the Who’s Keith Moon.

In the introduction, Wood mentions that he was taught how to read by a deconstructionist who would badger the class with the same question: “What are the stakes here?” The two voices mingling in this collection give a beautiful, moving sense of the stakes of criticism as Wood has practiced it, vigorously, without interruption for 30 years: What does it mean to do this work well, and what does it add to the world? What has it added to his life? Wood’s latest novel, “Upstate,” which follows a deeply depressed philosopher, dramatizes these questions about the relationships between analysis and fulfillment. He writes in that book: “If intelligent people could think themselves into happiness, intellectuals would be the happiest people on earth.”