In the past year three speakers have been disrupted at Harvard by aggressive hecklers--Weinberger, a Palstine Liberation Organization spokesman at the Law School and the Rev. Jerry Falwell at the Kennedy School.

"In some sense they [these incidents] may be straws in the wind. There's no crisis, but it's a good thing to talk about," said Dean of the Faculty Henry Rosovsky. "Any violation of free speech is disturbing."

Since the Falwell protest, the Kennedy School has adopted the informal policy of warning hecklers twice before ejecting them from the speech. A recent test of the policy came last October in an Institute of Politics debate, when one heckler heeded the second warning and was not ejected.

Although he has never directly dealt with freedom of speech in a public statement, Bok has written extensively on the related issue of academic freedom, opposing restrictions on scholars regardless of their political or professional opinions.

Free Speech an Issue in 1972

The issue surfaced in Bok's first year as president. A number of students, mostly members of the now-defunct Students for a Democratic Society, interrupted many of Herrnstein's lectures in 1971-2, protesting an article he had written which concluded that a significant measure of intelligence is inherited.

Herrnstein charged two students with harrassment, but the cases were eventually dropped.

Bok rushed to Herrnstein's defense, at least in principle. "I consider such personal attacks to be deplorable regardless of their status under the rules of the University" he wrote in 1972. "Attempts to discourage free expression cannot be justified simply because they are made in an effort to protect society from allegedly harmful ideas."

In his 1982 book Bok included an entire chapter on academic freedom, refining this argument but not significantly changing his basic position.

Charles T. Kurzman contributed to this report.