Writers who win the Nobel Prize for Literature do not often deliver memorable acceptance speeches, perhaps for roughly the same reason that Henry Kissinger became tongue-tied for once in his life when a woman approached him at a party and said: ''I've heard that you're a fascinating man; so fascinate me.''

But the Nobel Lecture for 1987, by Joseph Brodsky (who describes himself as ''a Russian poet, an English essayist, and . . . an American citizen''), was an exception. Not only did Brodsky rise to the occasion with one of the more daring celebrations ever written of the moral and political significance of literature. He even came up with a few sentences that managed to catch the attention of all the reporters covering the event.

The sentences were these: ''. . . there is no doubt in my mind that, had we been choosing our leaders on the basis of their reading experience and not their political programs, there would be much less grief on earth. It seems to me that a potential master of our fates should be asked, first of all, not about how he imagines the course of his foreign policy, but about his attitude toward Stendhal, Dickens, Dostoyevski.''

There are echoes in these sentences of a Russian tradition that attributes a transcendental importance to literature and that recognizes little or no distinction between its esthetic and its moral or spiritual dimensions. But more generally we have here a case of what the French call ''professional deformation.''

Like the most notorious American example of professional deformation in the realm of politics -- Charlie Wilson's ''What's good for the country is good for General Motors and vice versa'' -- Brodsky's statement attributes a wildly disproportionate role to his own field of endeavor. Ironically, however, whereas Wilson was not totally mistaken in identifying the fortunes of the United States with those of General Motors, Brodsky is entirely wrong about the relation between literary taste and moral or political virtue.

Actually, Brodsky himself supplies the best refutation of his own proposition when he acknowledges that ''Lenin was literate, Stalin was literate, so was Hitler; as for Mao Zedong, he even wrote verse.'' But having made this concession, Brodsky tries to get around it with a witticism: ''What all these men had in common, though, was that their hit list was longer than their reading list.''

Yet had their reading lists been longer, would their hit lists really have been shorter? Are we really supposed to believe that ''for someone who has read a lot of Dickens,'' to kill other human beings ''in the name of some idea is somewhat more problematic than for someone who has read no Dickens''?

In answering yes to these questions, Brodsky offers two arguments. The first is theoretical: ''esthetics is the mother of ethics.'' Therefore: ''The more substantial an individual's esthetic experience is, the sounder his taste, the sharper his moral focus.''

Well, speaking as one who has known large numbers of people with the widest range of esthetic experience and with the soundest taste in literature, I can only react with astonishment to Brodsky's assertion. Unlike him, evidently, I have found such people no better morally, and often much worse, than the less literate people I have also known. Indeed, I have found more spite, envy, cruelty, treachery and self-righteousness in the circles where esthetic experience and good taste are most highly prized than among, say, politicians or businessmen.

Brodsky's second argument for thinking of literature as ''a form of moral insurance'' against political ruthlessness is empirical. ''If only because the lock and stock of literature is indeed human diversity and perversity, it turns out to be a reliable antidote for any attempt . . . toward a total mass solution to the problem of human existence.''

But again, I have found that while literary people do tend (putting it mildly) to sympathize with human perversity, they are no great respecters of human diversity. If anything, they are more typically snobbish, dogmatic, intolerant and conformist with respect to the dictates of their own community.

Nor is it true that the great novelists and poets necessarily provide the kind of ''antidote'' of which Brodsky speaks.

Thus Brodsky singles out Dickens as a protection against ideologically inspired murder. Yet the deep influence of Dickens on the work of Louis-Ferdinand Celine did not prevent that evil genius of the modern French novel from becoming an enthusiastic fascist. And it was one of the English poets to whom Brodsky himself acknowledges a lasting literary debt -- ''my beloved Auden'' -- who as a young communist in the 1930s justified murder as ''necessary'' to the Revolution, and on another occasion called for ''the death of the old gang.''

These are not isolated or eccentric instances. On the contrary, many of the best writers of the 20th century have supported either fascism or communism.

It is also a fact that very few of the major novelists and poets of the age have had a good word to say for the bourgeois democracies. Yet these much despised societies have offered the only genuine ''antidote'' to the two murderous attempts in our time ''toward a total mass solution to the problem of human existence,'' and the only effective protection of the human diversity Brodsky holds so dear.

Does all this mean that literature has no moral or political value, or even that it is positively harmful? Plato suggested as much in proposing to banish the poets from his ideal state.

But it is not necessary to carry the argument quite so far. Literature can be justified in its own right by the delight and enrichment it gives to the mind, the imagination and the senses, and by the heightening of interest it fosters in life. It does not need and it cannot sustain the extravagant claims Brodsky makes for it -- understandable though it is that he should feel driven to make them at a time when poets are more likely to win prizes than to attract readers.