I take Mark Rothko at his word when he claims that an encounter with his paintings involves 'companionship' and argue that this insight reflects the artist's recognition that an observer and his work are in a relationship in which, as the German sociologist Hartmut Rosa puts it, 'both sides speak with their own voice'. To understand what this might mean, I first discuss Rosa's theory of 'resonance' and its importance for the study of art. Then, I explore 'resonance' in relation to Rothko, relating it to how he manipulated the language of painting to de-centre the normative visual perception of the observer, but also how he potentially opens this observer up to radically non-normative psychological and somatic experiences. The de-centring involves making space for an active relationship with Rothko's paintings which shifts the observer from the focused, outer-directed and controlling attention that usually dominates visual perception towards a more inwardly directed but more porous mode enacted under conditions of essential uncontrollability.