Many students, Illingworth says, simply refuse to take--or attend--9 or 10 a.m. classes, and 8 a.m. classes have almost entirely been eliminated. And this might be fine, except for the fact that "the Faculty are older and probably tend to live in the daytime world," Illingworth says.

Even if Faculty members were willing to offer classes later in the day, conflicts with Extension School classes and student groups about available classroom space would likely pose problems.

But perhaps the problem of absenteeism from morning lectures is not as bad as people make it out to be.

Roderick MacFarquhar, chair of the government department, moved his popular 10 a.m. class, Foreign Cultures 48: "The Cultural Revolution," up to 9 a.m. this year, without any negative effects on attendance, he says.

Of the 280 students enrolled in his class, the number that show up at 9 a.m. is "surprisingly good," he says.

It's possible that Lewis and Illingworth's backgrounds may make them particularly sympathetic to students' desire to keep weird hours.

"It would be hypocritical of me to object [to a 24-hour Harvard] on principle," Lewis says, "because that's the one I went to."

Lewis and Illingworth both recall 24-hour Harvard Square restaurants as well as an all-night bookstore.