Ask learned folk to list the most civilizing developments in history and you'll likely get: a) fire, b) language and c) the wheel. Not bad answers, of course, but they overlook the creation of the piano bar.

Hold on, hold on. Think about it for a second. What can be more civilized than listening to live music, sharing beverages and being able to actually talk with friends and lovers -- not shout monosyllables toward hand-cupped ears across the din?

So modern man owes a vote of thanks to the people at the Kings Loft in Alexandria. They offer a tasteful sanctuary on the Old Town waterfront where you can listen to the classy jazz piano of Tony Matarrese and watch the boats passing on the Potomac.

The brown-on-beige room is beautifully appointed and arranged: The tables are well separated -- no elbow-to- elbow intimacy with someone else's dangling conversation, no accidental angling for the wrong olive in the wrong martini. There are paintings, wall hangings and lots of greenery, a fireplace ringed by sofas and a metal fountain making its own music in the midst.

It's a fine place to settle in for an hour's or evening's conversation and listen to Matarrese play everything from "Satin Doll" to "Stormy Weather" to "Summertime" to "Smoke Gets in Your Eyes."

Matarrese, who was the official White House pianist for presidents Kennedy, Johnson and Nixon, knows he's a role player, and he plays it well. If folks want to pay more attention to each other than to him, that's okay. He's there if they want to listen -- playing sometimes for pride and himself, trying never to do the same song the same way twice.

It's not the White House days when he was playing with such visitors as Brubeck, Ellington, Hope and Sinatra. But there also aren't any 11 p.m. get-here-now calls; he has a Baldwin grand ("And how many people can say that?"); and there are no seats right around the piano, meaning no spilled peanuts or rattling drinks and a chance to play for everyone, not just the few around the keyboard.

The room itself, for all its charm, unfortunately is not a forgiving one. The acoustics are hard, closer to cafeteria than cabaret, so there are times when the music loses its duel with conversation. The drinks can best be described as "polite." And the presentation of the food -- desserts, cheese platters, appetizer-size plates of mussels, shrimp and the like -- can be curiously uneven. The shrimp dish, for example, came with a half-lemon, the rind partly peeled and tied into an intricate little bow. The cheese, on the other hand, just sat there, three hunks plopped on a plate, garnished with a knife.

On the matter of the river view: A building has the poor form to partly intrude, and a parking lot also sits between the third-story Kings Loft and the Potomac. Now if they could just get someone like Christo to throw a tarp over the whole thing.

Of course, no one ever said civilization was perfect. KING'S LOFT 121 South Union Street, Alexandria. Open 11:30 a.m to 2 a.m., Monday through Friday; noon to 2 a.m. Saturday; noon to midnight Sunday. Tony Matarrese at the piano, Tuesday through Saturday, 9 to 1. 836-7010.