FOR MANY PEOPLE, Roger Ebert was, is, and always will be a television personality. Television images are hard to shake, particularly when they’re nationally syndicated. Ebert’s show — co-hosted first, and most famously, with Gene Siskel, and later with Richard Roeper — could make or break a flick. It defined film criticism for over a decade, transforming it, to the frustration of anyone who considered criticism an exalted and solitary and written practice, into a popular onscreen pastime for two, comprehensible to most anyone, and condensable into a “thumbs up” or “thumbs down.” The show also defined Ebert in our minds: blazers, sweater vests, oxford shirts, unmoving eyes behind glasses, authoritative but dryly delivered pronouncements. Ebert was Costello to co-host Siskel’s Abbott: shorter, heavier, rounder.

Since Ebert’s prime, everything has changed: television is facing death by a thousand channels, TiVos, and webisodes; film criticism has become largely crowdsourced; and, most devastatingly, thyroid cancer has drastically narrowed Ebert’s face and taken his ability to speak, leaving him only the written word with which to communicate. But that’s plenty. Life Itself, a beautiful memoir of staccato sentences and chapters, covers the height of Ebert’s televised fame and the transition of his medium, his industry, and his health, and it shows that the heart of Ebert’s life lies offscreen.

Ebert began as a writer and remained a writer. He practiced journalism alongside Chicago Sun-Times legends like Jim Hoge and Mike Royko. He wrote deadpan new journalism-style interviews for Esquire, where he astutely championed a first-time filmmaker named Martin Scorsese. He collaborated with Russ Meyer on the cult hit Beyond the Valley of the Dolls and other films. He was the first film critic to win a Pulitzer, and he’s written voluminously: film guides, yes, but also a novel, a history of the University of Illinois, a walking guide to London, a copious blog, and now a memoir culled from that blog, sometimes word-for-word. As a result, Life Itself suffers occasionally from a sense of pastiche: some chapters seem thrown in for little reason, like a discussion of Ebert’s book collection, which fails to capture his genuine passion for the written word as wisely as his discussions elsewhere about, say, discovering Thomas Wolfe as a child, or being haunted and healed by Cormac McCarthy after surgery. Indeed, the book’s best moments, though well discussed on Ebert’s blog, are what TV’s constraints forced him to exile: the Midwestern childhood and the devastation of disease.

For fans of Ebert the celebrity, there are some big Hollywood names, the ones with whom Ebert got closer than the critic-subject relationship generally allows: Russ Meyer, Lee Marvin, Robert Mitchum, John Wayne, Ingmar Bergman, Martin Scorsese and Werner Herzog. (Other bold-face names — Coppola, Oprah, f...