Most professors and administrators are aware that academic freedom is in danger of being brushed aside by a public that has little understanding of what is at stake. They may be only marginally aware that the defense of academic freedom is endangered by certain confusions concerning the nature of academic freedom, the criteria for its violation, and the structure of an adequate justification for claims to it. These confusions were enshrined in some of the central documents on the subject, including the 1940 Statement on Academic Freedom and Tenure, agreed upon by the American...