With 1,021 students enrolled, Social Analysis 10: "Principles of Economics" again topped this semester's list of the 10 most popular courses--which for the first time in recent years consisted entirely of Cores.

The reduced number of Core classes, down this year to only 86 from the decade-high 105 offered last year, contributed to crowding in the remaining Cores.

Even Professor of Molecular and Cellular Biology William M. Gelbart's Biological Sciences 1: "Introductory Genetics, Molecular, Cellular and Developmental Biology," tenth on the list with 292 students, can fulfill a Core requirement.

However, instructors said they believe students make course decisions based on more than mere requirements.

"I'd like to think that there are compelling intellectual reasons other than that there are so few Core alternatives," said Hue-Tam Ho Tai, Young professor of Sino-Vietnamese history, who leads the ninth-ranked course, Historical Studies B-68: "America and Vietnam: 1945-75."

One reason for her course's popularity is its timeliness, Tai suggested, pointing to former Secretary of Defense Robert S. McNamara's recent memoir In Retrospect, which rekindled national interest in the Vietnam War era.

Neil Levine, Gleason professor of fine arts, pointed to growing interest in the famous Chicago architect as the lure for his course, Literature and Arts B-33: "Frank Lloyd Wright and Modern Architecture."

In fact, said Levine, he is serving on the advisory board for filmmaker Ken Burns' upcoming documentary on Wright.

Professor of Music Thomas F. Kelly also suggested that the course material was the main draw for his Literature and Arts B-51: "First Nights: Five Performance Premieres."

"I'm delighted, but I can't take credit for Handel's Messiah," he said.

Professor of Astronomy Robert P. Kirshner said he was excited to learn that his Science A-35: "Matter and the Universe," ranked sixth.

"I'm shocked, shocked to learn that A-35 is so popular--what's wrong with the other courses?" he joked.

However, he continued, there are drawbacks to so much unexpected student enthusiasm. The increased enrollment has forced Kirshner to schedule more sections and he may have to change the lecture location.

"I had a dark moment last night when I thought I should've limited the course," Kirshner said. "I won't, but it's a bureaucratic mess."

"All I can say is that nobody had better come in and ask to add the course on Monday, because I'm not going to do it," he added, laughing.

Kelly cautioned that the current enrollments can be misleading. Paine Hall, for example, can only accommodate 430 students, and because a greater number of students expressed interest in "First Nights," the instructors had to lottery the course.