In this short essay, Jean-Luc Marion pays fitting homage to Pierre Cahne by reading Stephen Mallarme's "With her pure nails offering their onyx high, horizontal ellipsis /Ses pur ongles tres haut dediant leur onyx, horizontal ellipsis " sonnet of 1887 with Martin Heidegger's phenomenological concept of anxiety. On the speculative hypothesis that Mallarme and Heidegger encounter the same phenomenon, as void and anxiety respectively, Marion stages an indirect meeting between the poet and the philosopher. This essay asks simply "what does the poet see that the philosopher does not?" and, inversely, "what does the philosopher understand that the poet does not?" In doing so, Marion approaches a synthesis of the two perspectives: reading Mallarme and Heidegger side by side allows one to see, like the poet, and to understand, like the philosopher, the same phenomenon. Through a close engagement with the finely balanced internal structure of the sonnet, alongside Heidegger's phenomenological descriptions, Marion shows how the inner reflection of the sonnet stages, poetically, the Nothing that Heidegger's fundamental mood of anxiety discloses, pulling each in directions neither alone would follow.