During a talk Friday with students at Columbia University, a Harvard Law School professor who is a vocal Zionist, Alan Dershowitz, called for nuanced and unbiased discourse about Israel.

“What I want to do is help you find ways to insist that as students at a great university, part of being educated is being taught the complexity,” he said.

The author of “The Case for Israel” spoke at the invitation of the Columbia student group Pro-Israel Progressives, which was formed to counter the perception that liberal students are less supportive of Israel than conservative ones.

Mr. Dershowitz said politics have nothing to do with it. “Support of Israel is not a left or a right issue,” he said.

He said he is opposed to professors bringing their pro-Israeli or pro-Palestinian bias into the classroom. After students accused a Columbia University faculty member, Joseph Massad, of displaying a pro-Palestinian bias, Mr. Dershowitz said he advised the university “not to fire Massad, but rather to bring on to the faculty objective, unbiased people who could teach the issue in a fair way.”

Now a similar issue has hit Mr. Dershowitz’s campus, with the publication of an anti-Israel paper by the academic dean of the Kennedy School of Government. Mr. Dershowitz said it is “worse than anything done at Columbia.”

Asked about the proper response, Mr. Dershowitz advocated for calm. “The best answer to radical anti-Israel rhetoric is not radical, unthinking pro-Israel rhetoric. It’s thoughtful, moderate conversation on both sides.”