But, amid a stream of gloomy news from Europe, including the downgrade of the debt of France and eight other countries, the sense that default is inevitable is growing. “When you simply go over the bare figures I can’t really imagine another scenario,” said Michael Fuchs, a leading member of Chancellor Angela Merkel’s Christian Democratic Union in the German Parliament.

“Mathematics is mathematics, and one plus one has to equal two and not five,” he said, describing how, even with a significant restructuring of its debt, the Greek government’s deficit would still be too large and its economy not competitive enough to put the country back on a sound footing.

That sense can be self-reinforcing as well, making it even harder for Mr. Papademos to push through the changes Greece needs to survive the current crisis.

Greece’s dire economic condition can hardly be overstated. After two years of tax increases and wage cuts, Greek civil servants have seen their income shrink by 40 percent since 2010, and private-sector workers have suffered as well. More than $75 billion has left the country as people move their savings abroad. Some 68,000 businesses closed in 2010, and another 53,000 — out of 300,000 still active — are said to be close to bankruptcy, according to a report issued in the fall by the Greek Co-Federation of Chambers of Commerce.

“It’s an implosion — it’s an endless sequence of implosions from bad to worse, to worse, to worse,” said Yanis Varoufakis, an economics professor at the University of Athens and commentator on the Greek economy. “There’s nothing to stop the Greek economy losing 60 percent of its G.D.P., given the path it is at.”

Still, more than 70 percent of Greeks say they want to stay in the euro zone — and they continue to believe that Mr. Papademos is the right man for a tough job. Yet the prime minister faces stiff, if stealthy, resistance from politicians who calculate that it makes no sense to risk their careers backing radical changes in the Greek economy that may ultimately fail to solve the problems.

There is ample evidence of Greece’s political dysfunction. About a year ago, after missing earlier fiscal targets, Greece promised to sell off $65 billion in state assets as a condition for receiving emergency loans. So far, though, it has sold only about $2 billion worth, because of domestic opposition and a reluctance to part with assets at what the government says are fire-sale prices.