It is hard to say. Certainly the tony, upscale Frog that closes tonight has long since been transformed from the Frog that opened in an erstwhile antiques store a block from its current location back in 1973. Frog was among the first of Philadelphia's "boutique restaurants," and dinner there had something of the quality of a high school play. If one of the exuberant young waitresses stumbled during her recitation of the daily specials from the blackboard menus, the ingenuousness of the error somehow added to the charm.
An effort - not altogether successful - was made to keep something of the ambiance of the old Frog when the restaurant moved to far more sumptuous quarters in 1980. Today a gilt-bordered blackboard hangs in the foyer with the message "Welcome to Frog" freshly chalked on it. But the specials are listed on a card that comes out of a computer printer.
The items that have remained big sellers on the menu over the years tend to be classics like rack of lamb, which may reflect a tendency among today's diners toward simpler taste blends. But it can hardly be argued that Frog is closing because Philadelphians have lost their taste for venturesome restaurant dining.
There may have been only a handful of fine restaurants in Philadelphia when Frog opened, but today there are dozens, many owned by people who served apprenticeships at Frog. And there has been a trickle-down effect as well. Philadelphians today can walk into an Irish pub and be confronted with a menu featuring pear-and-carrot soup.
Mr. Poses, for his part, does not see the closing as a watershed. "I don't think eras end, so much as they flow into one another," he said. He was initially surprised that so many people seem to be so affected by the Frog's demise, but now thinks he understands the sadness his contemporaries feel. ''We became a symbol of what it was like growing up in Philadelphia" during the 1970s and 1980s, he said.
On a recent evening, though, three women whose conversation made it clear they had dined at Frog many times over the years, clearly regarded the occasion of a final dinner at the restaurant as epoch-marking. They snatched matchbooks with the restaurant logo on them out of a bowl in the waiting area. ''This is history," said one, clutching her matchbook.