THE CURSE OF THE GIANT MUFFINS And Other Washington Maladies By Michael Kinsley Summit. 286 pp. $17.95

ONE IS often told that it is a mistake to assemble and republish one's already published writing -- occasional pieces, as curiously they are called. At least I've been frequently so told, for I have done it several times myself. I would defend this modest design for enhancing audience and earnings and do so now in the case of Michael Kinsley. We have here items, agreeably brief for casual reading (and sometimes better for their brevity), that are drawn from his offerings these last seven or eight years in The Wall Street Journal, Fortune, Harper's and most of all in The New Republic. They are admirably written, topical and informative, especially on Washington people, scene and culture.

However, the interest comes not just from the good writing, the clear, effective, resourceful prose, but also from the superb consistency of the author's views. Many writers move unpredictably between assigning virtue and assigning fault. It is, of course, far more important that people know what is wrong with them, and of this Kinsley is fully aware. Accordingly, he concerns himself wholly with people or tendencies that are morally defective, intellectually perverse, financially depraved or, by way of variation, "egregious," "odious" and "piteous." He wastes no time whatever on anything or anyone who is good.

The list of those so usefully characterized is very impressive. Ronald Reagan, perhaps needless to say. And Ed Meese and Howard Baker (widely, if inexplicably, admired). And members of the Supreme Court for Roe v. Wade. And James Buchanan, the last Nobel economics laureate. And Armand Hammer, Mary Cunningham, Tish Baldrige, Felix Rohatyn (the double Felix), Lloyd Cutler, Michael Deaver and a wide assortment of Washington lobbyists named and unnamed. And Ralph Nader, though he has some qualifying virtues. The list goes on. The editors of The Wall Street Journal, while modestly intelligent, are not so when editing Kinsley. Nor is Martin Peretz, the owner of The New Republic, when rejecting an adverse story of unspecified content on Edward Kennedy. An especially large number of other journalists are gravely wrong or inadequate, including Alexander Cockburn, William Shawn, James Reston and, on frequent occasion, the editors of The New York Times.

Some people of niggling tendency may think my praise of the author's consistency a trifle overdone. They will point to exceptions. And, admittedly, there are some. Thus on an early page he says in a wholly forthright and generous way that "{George} Bush is not stupid." That breaks with his pattern. But he goes on almost immediately to cite the vice president's "moronic toast" to Philippine dictator Ferdinand Marcos in 1981. To be not stupid but a moron is not unequivocally good.

There are other slight irregularities in his finding of ill fame. While hard on conservatives like Ronald Reagan or Michael Deaver, he is far more severe when he comes to liberals. This will trouble some of my faith, but again, in my own way, I would defend him. He is the editor of a liberal journal, The New Republic; as such, he undoubtedly knows more liberals than conservatives and knows them better. Thus he is better aware of our flaws and sees more urgently our need to be aware of them.

MUCH OF this book, as noted, has to do with Washington people and culture. I have not been so much in the capital in these last years and had not fully realized how bad everyone there had become. Kinsley himself deserves no slight credit for surviving so virtuously in such surroundings. But he is also pretty severe on the people of the Republic as a whole. He thinks Americans are given to silly fads and preoccupations, including nuclear war (such concerns he regards as deeply banal), the heart condition of Baby Fae, the immigration extravaganza at the Statue of Liberty, the Anglophilia displayed during the visit of Prince Charles and Princess Di and the pornography crusade of Attorney General Meese.

While I do not wish to dilute my praise, I do think that the educational effort by physicians and others on the nature of nuclear war has been both valuable and enduring and has even got through to the administration as it now seeks to counter it with an arms control agreement. On other matters, however, I am, as ever, admiring. My Scotch-Canadian ancestors were stoutly antiroyalist and strongly opposed, as is Kinsley, to making an expensive fuss over visiting kings and princes. At the Statute of Liberty celebration there was a shocking failure to mention the tens of thousands of us who came quietly (and in most cases very informally) over the Detroit River or down through Vermont and New Hampshire. We surely deserved one short but compelling speech.

It will be evident that I am more than slightly awed by Kinsley's criticisms and condemnations and the superior perception and moral purpose that they imply. I am even more awed that in reviewing this work I should find myself, in critical competence and moral certainty, in one order of magnitude above even Kinsley. The judge, no less, of the Lord High Executioner. Were I at all vulnerable to heightened self-esteem, this would be seriously damaging.

But enough. I hope everyone in Washington will read Kinsley. It will do very little for their self-esteem. But as he makes clear, the possibilities for personal improvement and reform are universal and simply enormous.

John Kenneth Galbraith is Paul M. Warburg Professor of Economics Emeritus at Harvard University.