Archbishop Arturo Rivera y Damas sought to put the most positive light on the stalemated talks between the Salvadoran government and its rebel opponents today, stressing that they had met for 12 hours last Friday and agreed to meet again was an encouraging development.

"To talk for 12 hours is not something useless, precisely because part of a dialogue is the confrontation of theses and points of view," Rivera y Damas said during the homily given at mass in the San Salvador cathedral this morning.

The archbishop, who has served as the moderator in the peace dialogue initiated in October by President Jose Napoleon Duarte, said that even though the results of Friday's second session at the seminary of Ayagualo "appear modest," there was value in the fact that both sides had "put to the test" the ability to "listen to each other."

In terms of negotiations, however, there seemed little doubt that both the rebels and Duarte's government had come no closer to an understanding since they first sat down to talk in the northern town of La Palma Oct. 15.

President Duarte's initial proposal, that the rebels lay down their arms and accept his offer to compete in the political process by entering next spring's national parliamentary and municipal elections, has been dismissed by the representatives of the Farabundo Marti National Liberation Front and its political wing, the Democratic Revolutionary Front as "simplistic" and "unrealistic."

The rebels have maintained that Duarte's offer at La Palma was based on the assumption, which they regard as false, that El Salvador under his presidency had changed dramatically and that opponents of the government could campaign in an election without fearing assassinations by death squads or "disappearances" that cut into their ranks before they took to the hills to fight five years ago.

Ruben Zamora, the head of the rebel's four-man delegation to the talks at Ayagualo, said yesterday that the rebels did not accept Duarte's premise because the death squads continue to be active, their members still go unpunished and the apparatus of state repression that drove the rebels into the mountains is still in place.

Similarly, Duarte rejected Friday a rebel "global proposal" for peace that would create a new, broad-based government, reform the constitution and drastically purge and reorganize the armed forces.

In Duarte's words, the rebel proposal that Zamora said was presented Friday as a basis for future negotiations amounted to a call for his government's "unconditional surrender" and a demand for him to scrap the constitution he is pledged to uphold.

Duarte's dismissal of the rebels' proposal was so categorical that Duarte's leading political opponent, former major Roberto D'Aubuisson, the leader of the extreme right and a man U.S. officials long have singled out as a key figure behind the death squads, said Duarte was beginning to sound like one of his rightist party's supporters.

Duarte said his rejection of the rebel proposal was based primarily on the fact that it was "unconstitutional" and that he, as the elected president of El Salvador, was committed -- by law, personally and at the insistence of the military -- not to stray from the constitution.

The fact that the constitution, drawn up in 1983 by a constituent assembly dominated by D'Aubuisson's National Republican Alliance, is not accepted by the rebels has left Duarte in the position of insisting, as the rebels see it, that the only way for peace negotiations to be conducted is by his rules.

This the rebels have refused to do, leaving the peace talks deadlocked with little sign of potential momentum, given the dramatically opposed analyses of El Salvador's crisis posed by Duarte and his opponents.

"In most negotiations there has to be a willingness to move toward each other's positions, even if they mean compromising one's deeply held convictions," said one diplomat here who has watched the talks closely. "Here there seems to be no give, or even possibility of give, whatsoever."

Duarte, for instance, made clear in a press conference yesterday that the "fundamental concept" of adhering to the nation's constitution in his proposal was "unmodifiable."

Even if Duarte were disposed to try to bend, it is highly unlikely that the armed forces, which so far have given only grudging and qualified support for his dialogue with the guerrillas, would allow it.

Traditionally a stronghold of the right, the armed forces remain tied to D'Aubuisson, even if its high command has been pursuaded to support Duarte because of his success in getting U.S. economic and military aid from Congress since he took office last June.

Even so, Duarte had trouble gaining the support of the officer corps last month for the Ayagualo meeting because of a right-wing campaign against the talks and because of the death last month, in a helicopter explosion, of Col. Domingo Monterrosa, the Army's leading field commander and a supporter of Duarte's dialogue.

The effect of the Army's acceptance was to tie Duarte's hands in negotiations by insisiting that the constitution be a basis of any settlement.

The rebel proposal is based on the opposite premise: that any settlement must come at the cost of a total revision of the government, the armed forces and the constitution. The rebels maintain that the segment of the country that they represent had no say in the crafting of the constitution.

"Frankly," said the diplomat after the talks ended Friday, "there does not seem to be much they can talks about beyond talking about more talks. That is a far way from negotiating peace."