The Marx­ist Frank­furt School’s prac­tice of neg­a­tive dialec­tics put the “crit­i­cal” in crit­i­cal the­o­ry, and none of its loose band of philoso­pher-crit­ics was as inci­sive as the dour, depres­sive Theodor Adorno. Against both mys­ti­cal and mate­ri­al­ist notions of his­to­ry as progress, Adorno argued in his trea­tise Neg­a­tive Dialec­tics that, writes Peter Thomp­son, “his­to­ry is not … Con­tin­ue read­ing Theodor Adorno’s Rad­i­cal Cri­tique of Joan Baez and the Music of the Viet­nam War Protest Move­ment