"I'm a very private person, and I don't want to be famous," said Czeslaw Milosz yesterday morning, bleary-eyed and dressed in bathrobe and slippers at his Berkeley, Calif. home.

But it was already too late. The 69-year-old poet, critic and novelist who teaches Slavic languages and literature at the University of California, Berkeley, was awarded the Nobel prize for literature yesterday -- the third American to win the prize in the last five years.

Born in Lithuania, Milosz writes in Polish and is relatively unknown in the West, where he has lived for three decades. In Eastern Europe, where he was once a hero of the anti-Nazi resistance, he is now treated as a non-person because of his opposition to communism.

He sought asylum in the West in 1951 while serving as cultural affairs attache at the Polish embassy in Paris. Milosz refused a recall to communist Poland, saying that he was remaining in France "because I knew perfectly well that my country was becoming the province of an empire."

"I have rejected the Stalinists' new faith," he said, "because the practice of lying is one of its principal commandments. The Soviet religion is only another name for lying."

His best-known work, a novel called "The Captive Mind" (1953) -- which analyzes the effects of communism on four imaginary writers -- is now out of print in the United States. His collected verse and prose is being published in seven volumes by Nowa, an underground, dissident publisher in Warsaw, where the underground published his anthology of anti-Nazi poems, "Invincible Song," during World War II.

Poland's leading literary critic, Arthur Sandauer, described the award yesterday as a political decision by the West. Jacek Kuron, a leader of political dissent in Poland, said, "the coincidence of this Nobel prize with the success of the Polish workers and intellectuals seems symbolic."

"Milosz owes his prize to those striking shipyard workers in Gdansk last summer," said a Polish journalist in Warsaw yesterday. A spokesman for the Polish intellectual dissidents said that the award will strengthen current drives against censorship, and "the government is going to have a difficult time figuring out how to handle this."

In America, Michael Leach -- president of Milosz's publisher, Continuum Books -- said yesterday, "We have only about 400 copies of 'Collected Poems' left in the warehouse. I think we'll be going back to press on that one." He estimated that about 3,500 copies of the book have been distributed since 1973.

"I am very honored and moved," Milosz said yesterday, "especially since I am a poet. As you know, poetry, especially that written in a lesser language, is not popular. This has great significance." He said that he expects to go to Stockholm on Dec. 10 to accept the prize, which amounts to $212,000 this year.

Milosz (whose name is pronounced -- approximately -- "Ches-love Mee-losh") is the ninth American to win the Nobel prize for literature. But only one of these latest three Americans -- Saul Bellow, who won it in 1976 -- was a native American who wrote in English. Isaac Bashevis Singer, who won the Nobel in 1978, was born in Poland and writes in Yiddish.

During his first press conference at Berkeley after the award announcement, Milosz read a poem, "A Magic Mountain," which says, in part: Wrong Honorable Professor Milosz Who wrote poems in some unheard-of tongue. Who will count them anyway . . . and describes the exile's feelings in California: I kept dreaming of snow and birch forests Where so little changes you hardly notice how time goes by. This is, you will see, a magic mountain . . .

At the press conference, he described himself as shy and said he "would like to continue with my very private and strange occupation." Milosz said that he may buy a farm with the prize money, that he does not consider himself a political writer and that "A Nobel prize-winner is not necessarily a very intelligent person."

Asked how the award would change his life, he said, "I would like to hold my class today." The remark was welcomed with loud applause by about two dozen of his students who were standing at the back of the room, probably wondering whether he would ever be back to finish his discussion of Dostoevsky.

After posing for pictures, he went off to the university's department of Slavic languages, where his colleagues held a surprise reception for him, singing "For he's a jolly good fellow" in Polish.

One colleague grabbed him by the shoulder and said, "A telephone call has just come from Stockholm. A mistake has been made."

"I could survive," said Milosz.

Milosz was born in 1911 in Vilna, a part of Lithuania which became part of Poland when he was 12 years old, and he writes in Polish. During the period between the wars, he became a socialist and a leader of the avant-garde in Polish poetry, and in World War II he was an active member of the Resistance, like Greek poet Odysseus Elytis, who won the prize last year. After the war, a collection of his poems, "Rescue," was one of the first books to be published in the People's Republic of Poland. As a war hero, he was rewarded with a position in the foreign service, and by 1951 was cultural attache in Paris. He wrote "The Captive Mind" to explain his decision in that year to seek asylum in the West.

Milosz moved to the United States from France in 1960, eventually became a professor at Berkeley, and established a reputation as a scholar to match his reputation as a poet. One of his books which remains in print, long after "The Captive Mind" has disappeared from circulation, is a history of Polish literature published by Macmillan in 1969. Two collections of his poems are available in English, the "Selected Poems" published by Continuum in 1973 and "Bells in Winter," published by Ecco Press in 1978.

Although he claims to be a "private person," Milosz seemed to be talking partly about himself last summer when he wrote an article about another poet in exile: Russian poet Joseph Brodsky. He said that poetry is a "sacred craft" and that "the poet must observe a certain code: be God-fearing, love his country and native tongue, rely on his conscience, avoid alliances with evil and be attached to tradition." He said that the poet should avoid serving men who wield power and "he will be helped by knowing how miserable their minds are."

In announcing the award to Milosz yesterday, the Swedish Academy praised the "uncompromising clear-sightedness" with which he "voices man's exposed condition in a world of severe conflicts." Milosz agrees that "my poetry reflects many of the horrors of the 20th century."

Among this year's 150 Nobel nominees, many were more famous and thought to have better prospects, including Graham Greene, Gunter Grass and Norman Mailer.

In his recent poem, "Ars Poetica," Milosz writes: In the very essence of poetry there is something indecent: a thing is brought forth which we didn't know we had in us, so we blink our eyes, as if a tiger had sprung out and stood in the light, lashing its tail.

Milosz's earliest poems, published in the 1930s, were experimental and apocalyptic works. Milosz recalls -- in his autobiography, "Native Realm" -- that in his youth he was "constantly visited by a feeling of imminent catastrophe . . . of planetary proportions."

His forebodings were fulfilled in World War II, which inspired some of his strongest writing. "Since I opened my eyes," he wrote in 1944, "I have seen only the glow of fires, massacres,/Only injustice, humiliation, and the laughable shame of braggarts." In 1945, he described himself as a man who: Attacks the past but fears, having destroyed it, He will have nothing on which to lay his head. Likes most to play cards or chess, the better to keep his own counsel. Keeping one hand on Marx's writings, he reads the Bible in private, His mocking eye on processions leaving burnt-out churches . . .

His poetry has mellowed considerably in the years since he moved to California. What was once cosmic catastrophe has become a sort of cosmic homespun in some of his recent poems. The tone is usually philosophical, the forms often miniature or built from small segments. The violence of the wartime poems has cooled into such expressions as the two-line "Longing" from his latest collection, "Bells in Winter": Not that I want to be a god or a hero. Just to change into a tree, grow for ages, not hurt anyone.

In the recent "Tidings," he presents a series of images of "earthly civilization" with rules. That every day lots were cast, and that whoever drew low Was marched there as sacrifice: old men, children, young boys and young girls.

But that image is only one of many. Most striking is his image of the age of space and electronics: We lived in a golden fleece, In a rainbow net, in a cloud cocoon Suspended from the branch of a galactic tree. And our net was woven from the stuff of signs, Hieroglyphs for the eye and ear, amorous rings. A sound reverberated inward, sculpturing our time, The flicker, flutter, twitter of our language.

After examining such conflicting bits of evidence, he concludes that perhaps we'll say nothing of earthly civilization. For nobody really knows what it was.