This rich selection of Mike Marqusee’s writing captures the kaleidoscopic mind of a polymath who delighted in deploying one sphere of knowledge to provide exhilarating insight into others. These pages illuminate the connections and contrasts between William Blake and Thomas Paine, Bob Dylan and Muhammad Ali, cricket and the nation state, Jewish identity and the BDS campaign, flamenco music and the films of John Ford, and the vagaries of political activism, often working closely with those who, subsequent to Mike’s untimely death in 2015, went on to lead the Labour Party. The extraordinary profusion of Mike’s interests was rooted deep in the soil of principles: a lifelong commitment to socialism, a recognition of the transformative nature of art, an expansive internationalism, and a commitment to intellectual and personal honesty heedless of cost. Acute and erudite, the pieces that make up Definable Traces in the Atmosphere reveal an intellect both serious and engaged. But Mike was never a writer who succumbed to the doctrinaire or the earnest. In marveling at this tapestry of some of his most memorable writing we can share another defining characteristic of its author’s outlook: a joyful appreciation that life’s pleasures are there for the sampling.