To the casual acquaintance, Kevin Pfeifer had a quiet, thoughtful demeanor that seemed of a piece with all the philosophy courses he took at Marist College. His gift for abstractions, though, was far exceeded by his taste for the concrete. And adventure.

He learned to fly, and logged 400 hours of flying time. He learned to sail, and loved to bring his friends out to race the tankers around Sandy Hook or his nieces and nephews out on Jamaica Bay. He loved to drive, and managed to sneak onto the secure grounds at Kennedy Airport, where he sped along a runway.

Mr. Pfeifer, 42, shouted with his life, not with his mouth. Growing up in Middle Village, in Queens, and spending many summer days in Breezy Point, he developed a close circle of friends who ate at Beefsteak Charlie's and joined him for his capers on the ground, at sea, in the air. He knew that fun was where you made it: he organized a legendary bash at an abandoned missile silo near Floyd Bennett Field in Brooklyn.

In Mr. Pfeifer's work as a city paramedic and later as a fire lieutenant, he had a knack for quietly bringing out the best in people, his brother Joseph said. Joseph Pfeifer was among the first battalion chiefs at the trade center on Sept. 11. He spotted his brother coming in with Engine Company 33, and the two Pfeifers exchanged a quick word, and then glances as they parted.