One cool night this month, small knots of men gathered around the darkened corners of the Plaza of the Savior to buy and sell home-brewed alcohol. The stream of cars darting into the shadows indicated that business was booming.

On a hot August afternoon, passers-by seemed unfazed by a worker sprawled unconscious on the lawn outside a television factory. His face was flushed crimson. The popular diagnosis was delivered in a word: vodka.

Then, last week, the communist daily Tribuna Ludu reported that Poland ranks third in the world in consumption of high-proof spirits -- a ranking that is much disputed by other sources.

The next day, another paper told of the arrest of an intoxicated mechanic in the town of Zgierz. He had commandeered a train to fetch a bottle of vodka from a friend, explaining that he was thirsty.

Such items are unremarkable in a country long plagued with a destructive pastime: excessive drinking. What is startling is that all this has happened in August, the "Month of Sobriety" declared by Poland's Roman Catholic Church.

Church officials say that up to 50 percent of the population will respond to their call for giving up vodka this month in the "protest against the plague of alcoholism." Yet the scale of Polish drinking, they concede, is such that little may seem to change.

Vodka, in its myriad Polish flavors and forms, remains even in August a staple of national life. It is the drink for every occasion, the hidden tonic of the workplace, even a weapon of political battle between the government and its church and political opposition.

"The dimensions of the present moral and social disaster," said a recent church statement, pose "a danger for the very existence of the Polish family and fatherland caused by drunkenness."

Despite two years of antialcohol campaigns by both the government and its opponents, 5 million Poles -- nearly 15 percent of the population -- are estimated to be problem drinkers. More than 320,000 were taken to the country's 52 sobering-up stations last year alone. Authorities recorded 11,500 cases of illegal alcohol production and linked alcohol to 85 percent of violent crimes.

Only in the Soviet Union, say experts and diplomats here, is the threat of alcoholism as grave as it is in Poland. Even as Soviet leader Mikhail Gorbachev has launched a campaign against drunkenness, Poland's experience is showing that a national habit so advanced is not cured easily by either decree or persuasion.

"Above all, drinking is a reaction of escape and exclusion," sociologist Mikolaj Kozakiewicz told the weekly paper Polityka. "We shall learn something about it when we examine the economic situation, people's anxieties and sense of danger, frustrations and feelings of impotence."

Shortages of food and goods, the lack of variety in entertainment and media and a national sense of depression following the downfall of the independent trade union Solidarity in 1981 all have frustrated authorities' efforts to control Poland's drinking, say Kozakiewicz and other sociologists.

History is also a factor. Experts here say Poland has had a drinking problem since it was first occupied and partitioned by foreign powers two centuries ago. With each foreign occupation since then -- and there have been several -- the intake of alcohol has increased, encouraged in some instances by authorities eager to pacify the populace.

Consequently, Polish nationalist opposition groups always have taken an interest in sobriety. The first trade unions opposing foreign occupation grew out of an antialcohol movement. A century later, shipyard workers in Gdansk banned alcohol during the strike that led to the formation of Solidarity.

"Vodka is public enemy number one, not of Polish health but of Polish independence," said opposition historian Bronislaw Geremek. "It is the best instrument for inducing the social state of passivity."

Under such circumstances, the battle against alcoholism in post-Solidarity Poland inevitably has turned political, pitting church against state, party reformists against entrenched bureaucrats, and supporters of the banned trade union against the administration of Gen. Wojciech Jaruzelski.

Perhaps the most vivid image of this year's antidrinking campaign was not the church-led pledges of Poles to swear off vodka but the sight of police arresting activists holding a "Sober in Solidarity" banner outside a liquor store.

"The government has the intention to combat alcoholism, and we also support the efforts of the church in this matter," said spokesman Jerzy Urban at a recent press conference when asked about the arrests. "But there are certain regulations about demonstrations that have to be respected."

The arrest of store pickets was not the first time government officals had attempted to undercut independent antialcohol campaigns. Last year, following a similar August sobriety appeal by the church and Solidarity, Urban announced that sales and consumption of alcohol were well above average during the month. The church said its surveys showed half of big-city residents did not drink.

"The authorities cannot tolerate any independent action, any spontaneous movement, even about alcoholism," said Marcin Przybytowicz, a former Solidarity activist who leads one of the several Brotherhood of Sobriety groups formed with the encouragement of the church. "And the problem with drinking in Poland is that there is no independent organization to fight against it."

Critics say the government has financial and political motives not to crack down on liquor. According to government figures, the state's alcohol enterprises are its most profitable and the government has obtained as much as 15 percent of its revenues in recent years from selling spirits.

Two years ago, the legislature passed a tough antialcoholism law that banned drinking in state offices, limited hours for sales by shops, funded treatment centers and led to sharp increases in vodka prices. A year later, the law was modified to eliminate plans for concentrating alcohol production and distribution in a central authority, apparently under pressure from local authorities and distilleries that had profited under the old system.

Meanwhile, many Poles responded to shorter shop hours and higher prices by buying or producing potent -- and often more dangerous -- substitutes. "An increasing number of people reach out for moonshine and even for such 'liquors' as methylated spirit, windshield spray, brake fluid or hair tonic," noted a writer in the Warsaw daily newspaper Kurier Polski.

Church and Solidarity activists say their appeals for sobriety have been more effective. But some concede that their motives, too, are mixed. "We have a double purpose," said Andrzej Stankiewicz, one of four Brotherhood of Sobriety members arrested for picketing a Warsaw liquor store. "What we want to do is, under the pretext of telling people not to drink, teach them to open their minds to reality and to the ideals of Solidarity."

Thus, when police quietly suggested that the alcohol picketers would be tolerated if they only changed the graphic style of the word "solidarity" -- done in their banner as in the union's logo -- the group refused. "We have to use symbols that give people the right information," said Przybytowicz.