The thousands of enthusiastic Greeks who packed Athen's Syntagma Square Tuesday night were celebrating more than just two years of Socialist government here.
They were also commemorating the rise to power of Prime Minister Andreas Papandreou, a maverick whose popular words and independent foreign policy, mixed with pragmatic acts, make him perhaps Europe's most populist leader.
Like almost everything Papandreou has ever done, Tuesday's ''celebration of change'' has become a matter of controversy. Opponents of the government have attacked the extravagance of the celebration at a time of severe economic troubles. Others complain that the festivities have all the elements of a personality cult. One independent newspaper published a cartoon depicting Papandreou standing before a bank of microphones on a rostrum, dressed in a Roman emperor's garb, soaking in the ''Ave Andreas'' cheers rising from the crowd below.
Whatever the merits of the criticism, the glittering celebration will certainly do little to provide an objective assessment of Papandreou's record at midterm. The reality lies somewhere between Socialist claims that the government has remained true to its promises and guided the country into a ''new era,'' and assertions of critics that it has violated its mandate, severely damaged the economy, begun to move toward a one-party state, and weakened the country's foreign relationships.
Political and economic realities forced Papandreou to alter his plans soon after he took office in October 1981. In foreign affairs he has: made his peace with the European Community (EC) from which he had threatened to withdraw, or at least seek a ''special relationship;'' done nothing to fulfill his pledge to withdraw from NATO, and signed a new agreement allowing US bases to remain in Greece for at least the next five years.
Providing sufficient incentive for his turnabout was nearly $2 billion in economic assistance and loans from various EC sources and the United States, the need to maintain the military balance with Turkey, and a keen desire to preserve access to technology to modernize the Greek economy.
Still, Athens has become notorious in the West for its independent positions and its willingness to voice them loudly. Its opposition to NATO's plan to deploy Pershing II and cruise missiles in Western Europe and its veto of a European Community resolution condemning the Soviet destruction of a South Korean airliner are only two prominent examples. Whether Papandreou's balancing act between East and West brings Greece greater benefits than a more traditional pro-Western policy is a matter of partisan debate.
''The issues are ultimately marginal. Greece can afford to take a maverick line because it is very important that Greece should remain in the West,'' asserted a Western diplomat. ''But of course there could come a point when the climate is so bad that it is difficult for ministers to defend a deal in the EC favorable to Greece.''
Whatever their politics, most Greeks appear proud of the new international prominence their country has recently achieved. Greece currently presides over the European Community, and will organize the EC summit for early December, a meeting considered by many to be one of the most important in the history of the Community.
Last week the Greeks interceded with Lybian leader Muammar Qaddafi at the request of France, and 37 French citizens who had been held in Libya were promptly allowed to leave. The various Lebanese factions and Syria have officially asked Greece to send observers to help supervise the Lebanese cease-fire. Pierre Elliot Trudeau of Canada, Indira Ghandi of India, and Sweden's Olof Palme also visited Athens this summer.
''Andreas has made us feel proud, whatever his shortcomings,'' admitted one critic. But many government detractors say, with some justification, that Papandreou's policies result in few tangible advantages over the previous, more cautious stances.
Domestically, the picture is equally mixed. The Greek economy has been in decline for four years, before this administration took office. After an initial fling with expansionary socialist policies, Papandreou has been forced, like socialist leaders elsewhere in the West, to adopt an austerity program.
Yet his retrenchment has not been total. He has reformed anachronistic legislation in social policy, and has pushed an ambitous reform of the national health-care system through Parliament - although the government has declined to say when it will implement the program, and critics assert that it never will be for lack of money. The Socialists have also passed legislation that businessmen and conservative politicians blame for creating a ''climate of fear.'' But even the ''supervisiory councils'' they have begun to set up to monitor industry have only vaguely defined powers.
On the other hand, the Socialists have curtailed the right to strike in the public sector - which accounts for over half of economic activity - but strengthened the positions of unions in the private sector.
In the eyes of many, whether these actions presage stronger measures in the future, or merely represent an attempt to placate the left of Papandreou's own party or the Communists, matters little. The results are the same.
''There are too many surprises,'' complained one business leader, ''the government has failed to establish clear, consistent rules of the game. We do not ask for special favors, only consistency.'' As a result, many businessmen fear that the government will seek to nationalize, or at least control, private industry through its ownership of banks and are therefore reluctant to invest.
Recent polls show that Papandreou's standing has slipped, but he remains by far the most popular politician in Greece. His next electoral test - the EC parliamentary elections in June - is still eight months away and is considered by many a dry run for the 1985 national elections.