Calvin Trillin, who since 1978 has been writing a "humor column" for The Nation, is quick to recognize the risks of his assignment: "In modern America, anyone who attempts to write satirically about the events of the day finds it difficult to concoct a situation so bizarre that it may not actually come to pass while his article is still on the presses." What is even more bizarre is the very notion of humor in the solemn pages of The Nation, a contradiction in terms if ever there was one. Yet, as many of the four dozen pieces collected in "Uncivil Liberties" attest, Trillin has brought it off.

At the outset, Trillin defined the column as "a thousand words every three weeks for saying whatever's on my mind, particularly if what's on my mind is marginally ignoble." He granted himself broad journalistic license: "I must admit that in these columns I haven't made a fetish of the old traditions of journalism--the tradition, for instance, of covering events only when they actually occur. . . . I am also free from whatever traditions journalism might retain in the area of fairness and civility." Thus well armed with wit and malice, he went right to work, conjuring up in his very first column "a remarkably prescient H.L. Mencken quotation that seems to have been making the rounds of Washington egghead circles lately":

"On those dark moments when I fear that the Republic has trotted before these weary eyes every carnival act in its repertoire, I cheer myself with the thought that someday we will have a president from the deserts of the Deep South. . . . The president's brother, a prime specimen of Boobus Collumnus Rubericus, will . . . gather his loutish companions on the porch of the White House to swill beer from the bottle and snigger over whispered barnyard jokes about the darkies. The president's cousin, LaVerne, will travel the Halleluyah circuit as one of Mrs. McPherson's soldiers in Christ, praying for the conversion of some Northern Sodom's most Satanic pornographer as she waves his work--well thumbed--for all the yokels to gasp at. . . . The president's daughter will record these events with her box camera. . . . The incumbent himself, cleansed of his bumpkin ways by some of Grady's New South hucksters, will have a charm comparable to that of the leading undertaker of Dothan, Alabama."

That paragraph, in which Trillin can fairly be said to have out-Menckened Mencken, became an instant classic--as well as a source for further irreverence in subsequent columns, in which Trillin took on such weighty matters as journalistic credibility and the protection of sources, and reduced them to the puddles of silliness they so often can be. Wrapping himself in a mantle of feigned self-righteousness, he took on one-by-one the members of the press who questioned the authenticity of the Mencken quote, including one who clearly had found him out:

"When I told one of them, Theo Lippman Jr. of The Baltimore Sun, that I had seen the quotation typed on a piece of paper rather than printed in a book or magazine, he asked if the piece of paper had been in a typewriter at the time. Such are the excesses of skepticism that respectable members of our trade have been driven to in this post-Watergate era."

As should by now be evident the temptation to quote Trillin is entirely irresistible. On the grounds that humor yields more to quotation than analysis, I offer these further gems from the Trillin lode:

* "The deduction for charitable contributions is simply the government's way of indicating that rich people are in a better position than poor people to decide which eleemosynary institutions are deserving of the taxpayers' support. Why else would coal miners be required to share the cost of a stockbroker's gift to the St. Paul's School's boathouse fund? The laws providing tax shelters reflect the strong philosophical commitment of the Founding Fathers, particularly Alexander Hamilton, to the principle that the public good would be served if dentists owned cattle ranches."

* "The presence of Carter in the White House, of course, is based on the belief that the proprietor of any middle-sized agribusiness can rise to the presidency if he simply works hard, studies at night with his wife to broaden their cultural horizons and keeps a low profile during civil-rights disputes."

* "Although a full week has passed since First Lady Nancy Reagan resumed her regular schedule, the White House remains unsuccessful in its efforts to still rumors that the cause of her brief absence was an operation for the surgical removal of her adoring smile."

As these passages make clear, the amiable Trillin can be a very tough customer. He is never more so than in this imagined passage from the undergraduate Harvard diary of Arthur Schlesinger Jr.: "Dear Diary, Today I asked those cool Kennedy boys again if I could play in their touch football game on the quad and they said again that I was a wonk and a weenie and a wimp and a grind and walked like a duck. I told them that someday I would be a famous historian and if they ever let me play with them then I would write whatever they wanted me to write." Poor Schlesinger may never again be seen in public.

Malice may not be nice in political humor, but it is necessary--and Trillin possesses it in ample measure. The persona he has adopted as humor columnist is that of a "sausage-eating, slothful crank" who views the world with unflagging irritation and a profound understanding that things can, and will, only get worse. In his jaundiced view, Julie and Tricia Nixon look pretty terrific by comparison with Nancy Reagan, and Billy Carter makes him yearn for Donald Nixon. The good old days really were better.

But with Trillin around it is all a good deal more bearable. Even in his less-inspired efforts--these tend to be the ones in which his wife and daughters figure, further proof that family matters are best kept that way--he is perceptive, funny and iconoclastic. There's nothing quite so refreshing as a grump, and Calvin Trillin is clearly a grump for the ages.