THE 1980s CAMPUS MOOD appropriated a weapon from the arsenal of the 1960s last week, as the sit-in returned to Harvard after a hiatus of several years. Only this time the site was Lamont Library, not some administrative meeting, and the demand was not for Black or women's studies, or for an end to Harvard's involvement in war-making, but for longer library hours.

This curious disparity between means and ends left not a few people confused, including several demonstrators. When librarian Heather E. Cole asked the 70 or so students who sat in their places after Lamont's closing hour whether they were prepared to leave, a lone protester shouted "Hell, no! We won't go!" Before the protest, organizers for GUERRILLA, the student activist group that planned the sit-in, said they would leave the library if administrators called the police.

GUERRILLA organizers noted that they did not intend their protest as a revival of '60s activism. And echoes of Vietnam protests and talk of police intervention were clearly out of key at a protest whose goal, after all, was simply to get the University to provide a round-the-clock studying area. The GUERRILLA members were rightly fed up at the snail's pace of the University's bureacruatic channels, and when Archie C. Epps III, dean of students, suggested to some at the sit-in that they bring their plan before the Committee on Houses and Undergraduate Life (CHUL), they pointed out that avenue had already proved fruitless.

The GUERRILLA sit-in showed two things. First, it was clearly effective: it got Dean Epps out at 1 a.m., and it got a 24-hour study area for freshmen in the Greenhouse Cafe (upperclassmen can already use their dining halls). Students with other complaints should note GUERRILLA's success, and realize that direct action can sometimes gain administrators' ears and solutions to problems where the "established channels" are sluggish. Ideally administrators would be more open to students' needs, but until the administration changes, students will have to act as well as talk.

But there was also a forlorn note to Tuesday night's protest, deepened by the occasional echoes of the conventions of 1960s protests. In that era, and as recently as the 1978 candlelight march protesting Harvard's South Africa-related investments, demonstrations sprang from a current of altruism. Today, as students devote ever more energy and time to the pursuit of their own advancement up the professional ladder of their choice, the weak sparks of protest spring instead from self-interest.

Students once used forms of protest like the sit-in to demand changes in a system they found reprehensible; today students use those forms to demand that they be allowed to participate in that system as effectively as possible. Let GUERRILLA and other students protest for longer library hours and the other little things that Harvard can do to make life easier for them; but let them do so only after they can say with truth that they have also protested about far worse problems that afflict people everywhere.