While the archaeological perspective has gained strength in recent years, Mr. de Montebello said he believed that the importance of ancient objects' exact historical context had been overstated.
"It is regrettable that archaeological sites, which since the beginning of time have been plundered, continue to be plundered and that in many instances important information is lost," he said.
But he added, "It continues to be my view — and not my view alone — that the information that is lost is a fraction of the information that an object can provide."
"Ninety-eight percent of everything we know about antiquity we know from objects that were not out of digs," Mr. de Montebello said, and he cited the Euphronios krater — painted by one of the most important Greek vase painters of antiquity — as an example.
"How much more would you learn from knowing which particular hole in — supposedly Cerveteri — it came out of?" he asked. "Everything is on the vase."
Mr. de Montebello took issue with archaeologists like Malcolm Bell of the University of Virginia, who directs excavations at Morgantina, the ancient city in Sicily from which many experts believe the Met's Hellenistic silver was looted from a third-century B.C. house. For years, Mr. Bell has led the charge to have the silver returned.
But Mr. de Montebello insisted that Mr. Bell's certainty about the silver's origin, which is not shared by all archaeologists, was damaging in itself.
"I will concede that it is wrong — and clearly wrong — to remove objects from a site clandestinely without proper documentation," he said. Yet he added, "To perpetuate forever that these things come from Morgantina, that is also a sin."
When a reporter mentioned that Mr. Bell had shown him the hole in Morgantina where Italian officials said the silver was found, Mr. de Montebello bristled.
"There are lots of holes in Sicily — please," he said, betraying an impish smile. "And lots of people smoke. And I believe in Santa Claus, too."
In a telephone interview on Monday, Mr. Bell denied that he had ever claimed absolute certainty about the origin of the silver. "The issue is, when objects are removed from their original context illegally and clandestinely, it is very difficult to prove they are from a particular place," he said. "If you can produce a convincing case for their source with the evidence you have, then that's what you are obliged to do."