IT'S A CLICHé, I suppose, but to witness someone in the process of dying is to appreciate the daunting task of being alive. When my father was in the last stages of bone cancer, it was painful to witness how the disease had thinned away not only his formidable body but also the heavy assurance with which he had once carried it. The disease revealed the many layers that made up the idea he had of himself and left a voluble man almost wordless, in an aching quiet from which we all longed for him to be free. The great triumph of Wit, Margaret Edson's gorgeous, Pulitzer Prize-winning play now on imperfect but wrenching display at the Seattle Repertory Theatre, is the way in which it almost tangibly sinks through those layers and arrives with shining immediacy at the language of a fearful human heart. In a heady, often vividly funny work that bemoans our prideful use of language as surely as it celebrates the beauty of every word, Edson provides deliverance with a heartbreaking definition of what it means to be free.

"It has always been my custom to treat words with respect," says Dr. Vivian Bearing (Megan Cole), author, professor, and John Donne scholar; and Wit is an evening spent with her as she rallies that one defense against an ovarian cancer that cares nothing about her mental prowess. She claws at everybody -- at her doctors, at us -- in an effort to cling to the words she's always used to cover a very raw soul, even reciting Donne's Holy Sonnet VI ("Death be not proud...") during a gynecological exam. Vivian feigns comfort narrating the vocabulary of her impending death but denigrates any emotions we may bring to her plight, sighing, "I cannot believe my life has become so corny." She initially shuns the comfort of her down-to-earth nurse (played by a warm, winning Liz McCarthy) as surely as she welcomes the challenge presented by the socially inept medical fellow Dr. Posner (Brian Dillinger), who sees her cancer with the same unfeeling zeal with which Vivian views punctuation.

Cole's work here in the crucial lead role is as flawed and impossible to ignore as her character. Her interpretation is heavy on technique, with a raspy, distinct vocal quality kicked up several notches into the bone-rattling barks of an Ivy League Patton. Her clipped, rhythmic speech pattern feels as though it were set in stone, and every choice she makes is unrelentingly, rather fascinatingly huge. This is disconcerting, but give her time--because Cole's severe rendering of Vivian's impenetrability makes the character's pains and revelations that much darker.

Cole's right in sync with her director, Martin Benson, whose approach is to come down on top of the material and squeeze his way into the corners rather than come up from underneath. It's a style that thrashes the play about soundly and sometimes leaves no nuance unturned. If there's a flaw to Edson's work, it's that the passionate minutiae of the play's many levels often linger on the edges of didacticism. Benson blows them up until you can't look away, but that's a double-edged sword. His grasp of the play's howling sorrows will bring tears to your eyes as surely as his excitability will weaken your response to his other players. Dillinger's young upstart, in particular, is too cartoonishly awkward for us to believe he's a star pupil -- he's simply first in a class of other buffoons. Edson wants us to link the steely obsessions of her doctors with Vivian's literary fastidiousness, not hover above them, clicking our tongues in judgment. She's surely critical of a certain element of the health care profession, but her main concern is the walls that allow a clinical approach to living.

Whatever the faults of this production, those walls do come crashing down, and the cathartic uplift that results from that devastation is not to be missed. Benson and Cole dig in fiercely, and their affectations eventually complement the density of the piece. As Vivian's personal journey reaches the breaking point, Cole's flinching tenderness and frightened rages intricately strip away her original façade; if you don't cry, you're likely made of the same stone that Cole's take on this woman originally suggests. The reappearance of Vivian's former mentor (Jean Burch, who shuffles about with a soft dignity) is only further need to wring out your handkerchief.

Wit is a play that brings a discussion of grace all the way down to the level of a human cell, to a semi-colon. It's a breathtaking evocation of the fact that words can lead us to the truth, even though we're usually taking them the other way.