AROUND 32 YEARS AGO, a few months after The Groves of Academe was published, Gilbert Highet, surveying the world of letters as if from Olympus, concluded, "In America the most effective satirist is Mary McCarthy, who writes a peculiarly cold but skillful prose, as graceful as a deft surgical operation."

Fourteen books later we know there has been much more to Mary McCarthy -- she's now 72 -- than dissections of Colonel Blimp college presidents and sleazy professors of literature who defend themselves against discharge on the grounds they were once communists. Not only has she written rapier novels. She is a clear-eyed, cool-voiced analyst of human behavior and one of the few commentators on the arts for whom the term "critic" seems barely adequate. She is nearly a national cultural asset, and the pieces retrieved for Occasional Prose show us why once again.

Gathered from lectures in unlikely places like Kansas, Poughkeepsie, and Aberdeen, from prefaces and postfaces to several books, from such publications as Saturday Review, The New York Review of Books, The New York Times and Britain's Observer and Sunday Times, these 21 selections range from obituaries of friends who fought the battle of liberalism to reports of social disorder visited on us by the Vietnam war, from accounts of Richard Nixon's debasement of our language and the romanticism of Boris Pasternak to insights into the penny-pinching meanness of the French petite noblesse and the eccentricities of those who devote their lives to plants.

In a preface to Jean-Francois Revel's Without Marx or Jesus, Mary McCarthy tells us, "There is something wonderfully disinterested about Revel's biases, a joy in bias itself as an artistic form . . . He has a Falstaffian side and only cares that his 'slant' should run counter to respectable culture and received opinion. If he has a personal grievance, it is a long-standing, deeply nurtured one against the immovable forces of entrenched beliefs that insult his sense of the self-evident."

We admire in others the qualities we ourselves possess. Revel's independence of mind and his enthusiasm for turning conventional wisdom upside down -- maxims like "War is a continuation of politics by other means" reversed into "Foreign policy is an initiation of war by other means" -- are essentially what attract us to Mary McCarthy. She is Irish, had a Jewish grandmother, got her Phi Beta Kappa key at Vassar and began her writing career on the Partisan Review. She may have both genetic and acquired contrariness. And it has the right targets.

"If I hear often enough 'Poverty is no crime,' I feel an urge to reply 'Poverty is a crime,' meaning that it is against the laws of humanity or that to be poor is to be already two-thirds of a criminal in the eyes of the police."

While she doesn't believe that the 1968 Whitehall antiwar demonstration she covered in London gave the U.S. a push toward withdrawal from Vietnam, she suggests "another way of looking at the question." She turns it around. "What would not demonstrating have accomplished? . . . Nothing. So given the choice between a problematical nothing and a certain nothing, maybe it was best to demonstrate after all."

This thought follows, by the way, her observation that to ask demonstrators, "What do you hope to accomplish?" had "the effect of a negative password. It virtually invited the bum's rush." Such commonsensical questions were "an unwelcome interruption in a theatre of revolution." McCarthy takes sides but not blindly.

She thinks about writers and writing with this same sort of pollution-free intellect. "In the realm of ideas," she says of her friend Hannah Arendt, "Hannah was a conservationist; she did not believe in throwing away anything that had once been thought. A use might be found for it; in her own way, she was an enthusiastic recycler."

Phillip Rahv, her old mentor at Partisan Review and grand pooh-bah of the U.S. literary left, knew America intimately but lived emotionally in the ghetto of his Jewish Ukrainian past. "He never learned to swim," she says. "This metaphorically summed up his situation: he would immerse his body in the alien element (I have nice pictures of him in bathing-trunks by the waterside) but declined or perhaps feared to move with it. His resistance to swimming with the tide, his mistrust of currents, were his strength."

TO READ Mary McCarthy is often sheer pleasure. Her mind works like bright light, showing us details that redefine what we thought we had seen before. Her sentences are displays of grace.

Vladimir Nabokov "has been trying throughout his career to make a one-man literary restoration, using his prodigious memory to undo the present." While the Russian Revolution as described by Boris Pasternak "still has some of a Tolstoyan natural force, awesome and fierce . . . in Solzhenitsyn, the savage natural is replaced by the universal ordinary." From Henry James on, our expatriate writing has a "certain Jackie-and-Ari color supplement flavor" as characters appear to be "impersonating figures in a work of art -- something few people dare to do at home." During the 1920s "there were more converts made to hedonism than to any other faith, and that may still be the message of the most influential fiction of today, from Mailer to Updike."

Reviewing Italo Calvino's voluptuous The Castle of Crossed Destinies, Mary McCarthy notices that "the act of reading, when finally consummated, is seen to be parallel to the act of love." In an essay on the Italian critic and leftist Nicola Chiaromonte, she notes that "the theatre is dependent on numbers, both to produce it and to consume it. Far more than the novel, or say, the sonnet, it is keyed to demand . . . The sociability of the theatre distinguishes it from films, where one sits in the dark . . . One is never lonely in the theatre."

The motor that runs Mary McCarthy is powerful but different. She believes, for example, that fiction may not change societies but changes individuals the way falling in love does. As a result of reading John Dos Passos' The 42nd Parallel at the age of 20, she went from political royalist to liberal socialist. She believes that "if beauty is good for something, then it is a mysterious something that we today cannot put our finger on." But she knows that "everyone needs the good, hankers for it, as Plato says, because of the lack of it in the self. This greatly craved goodness is meaning, which is absent from the world, outside the chain of cause and effect and incommensurable with reason."

Mary McCarthy's purpose in writing is exactly this: to find meaning, to make order of human expression and action. I do wish in this particular book she had left out her rewrite of the plot of La Traviata for a Metropolitan Opera guide book and had passed up the temptation to memorialize her garden pieces. They're geese among swans. The rest of the essays in Collected Prose are the goodness she and we crave: gorgeous meaning.