All Dr. Katz's students admired how quickly he expressed a point, often through tidy lists. In honor of that style, I want to focus these remarks about Michael Katz and activism on four dimensions: (1) his understanding of the activist/academic tension; (2) how he advised his graduate students to wrestle with it; (3) how he engaged nonhistorians; and (4) how his work's prognosis of the prospects for social change transformed markedly in the last five years of his career.