Far be it from us to argue, but the Gibson Sotheby's listing for this 4-BR, 3.5-BA duplex on Beacon Street claims that it contains "one of the Back Bay's most elegant fireplaced dining rooms." Nah. We'd pretty much say it's the most elegant, at least for a long while. The 3,970-square-foot duplex, which starts on the second floor of a Civil War-era building, is on the market for the first time since 2004, when it traded for $3,500,000, for $6,500,000. Along with the dining room, what also grabbed us by the lapels was the above bedroom, which has two Buddhist statues flanking a bunk and what we can only imagine is the serenity of the Charles River views beyond.