This paper aims at surveying the experience of an impossibility of writing in Ese hombre y otros papeles personales by Rodolfo Walsh as an exposition of impotence. To this end, several entries from the "Diario" will be examined, as in these such impotence —fundamentally linked to Novel writing— is manifest in its various shapes, and a hypothesis on their nature starting from the idea of writing matter as possibility will be tentatively put forward, supported by Giorgio Agamben's works