Abstract: Like everyone else, academics are susceptible to informational and reputational signals. Sometimes academics lack confidence in their methods and beliefs, and they pay a great deal of attention to the methods and beliefs of others. The academic study of law is particularly subject to cascade effects, as people follow signals that they participate in amplifying. Some of these effects run their course quickly, whereas others last a long time. Leaders can play a special role in starting and stopping cascades; external shocks play a special role in the academic study of law; sometimes like-minded people within academia move one another to extremes. This informal essay, the Foreword to the forthcoming annual book review issue of the Michigan Law Review, discusses these points in a tentative and impressionistic way, with brief comparisons to other fields.