The article confronts genre theory with considerations of temporality. Starting from the assumption that the genres of essay and manifesto lend themselves to divergent constructions of time, it interrogates the artificiality of generic demarcations and highlights formalisations of time in the blended genre of the essay manifesto. Considering select representative texts, the article brings into view manifold dynamics that might otherwise be missed, especially with regard to temporality. Rather than assuming contrastive constructions of time on a spectrum of tension between the poles of duration (length of time and permanence) and momentariness (brevity and transitoriness), the article introduces the concept of dialectical gestures of time in the sense of two interrelated, mutually constitutive notions of momentary duration and enduring momentariness. As is shown, foregrounding dialectical temporal gestures in the essay manifesto highlights critical functional aspects of this form, including polemical disruption and explorative reflection.