From Robert Nozick‘s final interview:
The Harvard graduate students of the late 60s and early 70s were the center of SDS activity on campus. I had been here for two years as an assistant professor, and left and went to Rockefeller University for two years, and came back in 1969 when I was 30 years old as a full professor. In the previous semester, students had taken over the university’s main administration building; their occupation was ended by police action. Feelings ran high. I announced a course, and it was printed in the catalog, titled “Capitalism,” in the philosophy department. The course description was “a moral examination of capitalism.”
[…] Somehow a rumor had spread, or maybe they saw what books were there in the textbook section of the bookstore, where in addition to something by Marx and some socialist book were Hayek and Mises and Friedman. So one graduate student came up to me at the beginning of the term and said, “We don’t know if you’re going to be able to give this course.” This was a graduate student in philosophy. And I said, “What do you mean?” He said: “Well, you’re going to be saying things…” and he mumbled something, “there may be interruptions or demonstrations in class.” And I said — I was then, you have to remember, 30 years old — I said, “If you disrupt my course, I’m going to kick the shit out of you.” He said, “You’re taking this very personally!”
[…]I said, “It’s my course. If you want to pass out leaflets outside the classroom door, and tell people that they shouldn’t come in and take the course, that’s fine. I won’t allow you to do things inside the classroom.” He said, “Yes, well, we may pass out leaflets.” Time went by and nothing happened during the first week, the second week. So I saw him in the hallway and asked, “Where are the leaflets?” He said, “Well, you know, we’re very busy, we have a lot of things to do these days.” I said, “I called my mother living in Florida and told her that I was going to be leafleted, now come on!” But nothing ever happened.