Paul Cella, a talented writer I have not run across enough in recent years, has written a polemic against the propositions that our political life must treat all questions as open questions and that seditious or revolutionary movements should not be “the subject of firm legal and political sanction.” I agree with much that he has to say. My principal disagreement is that his essay assumes that people who value the openness of American society necessarily affirm these propositions. I don’t think it is at all reasonable to see positive references to America as an “open society” as endorsements of everything John Stuart Mill or Karl Popper had to say about the subject.