The Executioner’s Smile : ON THE FIRING LINE : The Public Life of Our Public Figures <i> by William F. Buckley Jr. (Random House: $22.50; 499 pp., illustrated; 0-394-57568-7) </i>

Marcel Proust’s housekeeper once declared that after working for Proust all others seemed quite vulgar. It is not unlikely that Bill Buckley feels the same way about William F. Buckley Jr.

Buckley is more than “Everyman”; he is “Everywhere.” His talents, protean is the only word for them, were never more vividly exhibited than in his own account, in the New Yorker magazine some years ago, of his “work week.” The velocity of Buckley in action resembles nothing so much as a cyclone rakishly invading the culture of a neighborhood. Sailor, editor, publisher, columnist, novelist, political philosopher, essayist, social critic, conservative grouser, apostate Yalie, he is the contemporary mirror of a Renaissance man moored somewhere between Voltaire and Ronald Reagan.

But it is television that catapulted Buckley so grandly from a mistily observed right-of-center grand vizier to a public icon, only slightly less publicized than Geraldo Rivera. And it is his “Firing Line,” public television’s longest running program (it began in 1966, predating Public TV) that is Buckley’s national rostrum.

This volume is an exegesis of the best of “Firing Line,” assembling mannerly and witty exchanges between Buckley and his guests, smeared generously with what Buckley would call “orgulous” musings.

I am not one to reread in hard cover that which has been published in daily newspapers or performed on TV. A merry band of syndicated columnists makes a nice living stirring old porridge. But I exempt “On the Firing Line.” If you enjoy literary karate chops, delivered with elegance, this book is for you. Dullness is the one sin for which there is no expiation. Whatever one thinks of Bill Buckley, and the possibilities are tauntingly delicious, he is rarely dull.

You have to picture Buckley on the tube, clipboard on his lap, lounging indolently, casting a half-lidded gaze at his high-powered guests, interrogating them with an intermittent patrician stammer which is genetically connected to high-born Englishmen, and then spearing them with a lance dipped in curare while they haplessly flap about in some confusion. But often Buckley extracts from his guests the best that is in them.

Consider that celebrated White House aide and recent felon, G. Gordon Liddy, discoursing on violence in the community: “The experience of mankind is that the big fish eat the little fish, that Jaws is still out there, not Charlie Tuna.”

Or Al Capp, the creator of “Li’l Abner” when Buckley queried him about a Harvard dean: “And what caused Dean Monroe, in your opinion, to make this error in judgment?”

Says Capp: “Because he’s a fathead.”

One of Buckley’s favorite guests is the famous professor, John Kenneth Galbraith, who when he unreels himself is some 6 feet 8. Ostensibly ideological enemies, in real life Buckley and Galbraith are neighbors in the posh Swiss countryside where they repair each year to unburden themselves of yet another published volume.

When Buckley chastises Galbraith about lying about with his hatchet on the corporate rich, Galbraith lobs this one: “One of the marvelous good fortunes of being an author that I share with Buckley is that authors, unlike automobile companies, are not yet required to recall their defective works.”

When Rosalyn Tureck, renowned harpsichordist and pianist, comes aboard, she recounts a famous pianist who performs for recordings the C-Minor Chopin in about 3,000 takes so that innocent listeners would believe it was a seamless web of excellence. Said Buckley: “He should have left in one mistake to make it plausible!”

Every now and then a guest scores. Witness Michael Kinsley, editor of the New Republic magazine. Said Kinsley to Buckley, “I have a reform for you and it sounds so perverse I think you will like it.”

Buckley impales Robert Schrum, one of the finest artisans of the political speech, with this: “Mr. Schrum, you spent a lot of time in the opening program to discuss this question. I would like to take you seriously, but to do so would be to affront your intelligence.”

So it goes. Go buy “On the Firing Line.” If you don’t summon up a few chuckles and/or an ascending sense of enjoyment, you’ve got the ranch, the drugstore and the bowling alley. One confession. I am now, always have been, a fan of Bill Buckley, so factor in that bias when you make your own assay.