The Socialist Youth organization here has campaigned against compulsory military service and publicly mocked the Army's May Day parade. The youth magazine Mladina has argued that undemocratic election procedures make the authority of the federal prime minister illegitimate.

At Nova Revija, the local intellectual journal, an editor casually reported that its staff has "no illusions about the vitality of Marxism." He added: "After all, Marxists can be dangerous."

Almost anywhere else in this Communist-ruled country, such open expressions of dissent would invite a jail term. In Ljubljana, capital of the Yugoslav republic of Slovenia, however, a liberal local party leadership has taken advantage of its increasing autonomy to allow a climate of tolerance unthinkable five years ago.

"The Slovenian authorities are willing to tolerate our criticism because they want to show our republic as special and promote our independence within the federation," said sociologist Dmitrij Rupel. "As Slovenes, we have common enemies. All of us see the threat of centralism and domination by Belgrade."

The Slovenes' defensive, locally managed pluralism is one sign of how fragmentation of authority has changed Yugoslavia since the death in 1980 of Tito, the country's last strong leader. Under the decentralized system left by Tito, government power increasingly has been taken over by the country's six federal republics and two autonomous regions while a collective and largely anonymous federal leadership acts only by unanimous consent.

Yet even as Slovenes have welcomed the changes, Yugoslavia as a whole has been gripped by economic disorder, bitter nationalistic feuding and apparent political paralysis. As the country approaches the landmarks of the Communist Party congress and local and national government elections, much of the political establishment appears at last convinced that Tito's bequeathed political system simply has not worked.

"At one time we gave the republics too little possibility to govern themselves, but now we have gone to the other extreme. Instead of a one-party system, we have eight one-party systems and eight closed economies," said Najdan Pasic, the president of Serbia's constitutional court. "Factional interests have become institutionalized and are so strong that they can paralyze the system as a whole."

Examples of the resultant irrationality abound. Pasic said a train regularly leaves the province of Vojvodina, a grain producer, with wheat shipments, crosses Serbia and drops off the wheat for export at the Adriatic Sea port of Split. The same train then picks up wheat imported from abroad to deliver to Serbia -- since Vojvodina's authorities would rather export than sell wheat to another republic. Meanwhile, the train must change locomotives several times because of the insistence of the various jurisdictions on maintaining separate railway systems.

On a broader scale, Yugoslavia's economy has been crippled by the duplication of industrial and agricultural investments by neighboring goverments and the upsurge of nationalism by its seven major ethnic groups, each of which wields decisive influence in one of the republics or provinces. The national organization of the Yugoslav League of Communists, as the ruling party is known, and the federal government, both led by eight-member collective presidencies representing each jurisdiction, have been stymied by the ability of one member to block any major initiative.

So far, efforts to change the national political equation have been one of the best illustrations of its difficulties. After years of work and long debates within the League of Communists, a commission charged with examining proposals for political reform issued a "critical analysis of the political system" early this year that suggested only minor measures. Nevertheless, Yugoslavia clearly has moved toward greater federal centralism in economic matters in the last year as the International Monetary Fund and western creditors holding its $20 billion debt have pressed for change. Although predicting that few new initiatives will emerge from the party congress in June, many officials and politicians believe that similar political reforms are sure to follow.

For both federalists and republicans, the question is how far the recentralization of authority will go -- and whether it will reverse the political and economic liberalization that has developed in recent years.

Advocates like Pasic say increased federal authority will allow Yugoslavia to unify its badly divided internal market, enforce market-based economic efficiency over the nationalist and protectionist instincts of local republics, and prevent one rebellious jurisdiction from thwarting the other seven on common national policies.

Yet politicians and intellectuals in Slovenia and neighboring Croatia, which oppose most proposals for reform, warn that the country is drifting toward a different kind of centralism that will simply stifle economic initiative with administrative controls and reverse the trends toward increased local democracy.

"Everyone knows there must be changes, but the answer is not a central power that can dictate a way out," said Marjan Sedmak, a writer on the Slovenian newspaper Delo. "The answer is a central power that will guarantee more economic freedom, self-management and democracy. But that's not the way we're going."

For all sides, much of this complex debate has been focused by the expected installation in May of a new federal government, and the selection -- after a bitter behind-the-scenes struggle -- of Branko Mikulic, a Croat from Bosnia-Hercegovina, as its prime minister.

Mikulic, a 57-year-old former party chief in Bosnia and now a member of the collective presidency, won renown in Yugoslavia by serving as an efficient organizer of the 1984 Olympic Winter Games in Sarajevo. According to several informed accounts, divided party and republican officials turned to him in the hope that he could bring more discipline and efficiency to the federal government.

Western diplomats and many supporters of political reform have since welcomed the prospect of Mikulic at the government's helm.

Intellectual dissidents and many liberal politicians, however, describe Mikulic as a standard-bearer of the totalitarian-style centralism that is the risk of increased federal power.

Predictably, some of the sharpest and most public criticism of Mikulic has come from Slovenia and its aggressive press.

"Mikulic is the kind of person who could say that the cause of inflation is not bad spending but the class enemy -- like this magazine," said Miha Kovac, the editor of Mladina, which has attacked Mikulic's election as undemocratic.

Nevertheless, Kovac and others here predicted that they might ultimately be protected by the very entanglement of the country's political system.

"The fact is that nobody in Yugoslavia is powerful enough to carry out big changes, either for centralization or for democratization," Kovac said. "That's our pride, and our curse."