This chapter explores the unsayable in twentieth century poetry, namely in poems by R.M. Rilke, W.B. Yeats and Dylan Thomas. When approaching apophasis, poetry engages in philosophy, exploring the nature of existence and of perception as well as the limits of language. Müller argues that, contrary to the dreams of the Romantic poets, there is no great hope in twentieth century poetry to achieve an articulation of the mystery of being but rather delivers, paradoxically, formulations of its unknowability and inexpressibility. This consciously performed inability to speak other than in open questions or proclamations of unsayability is viewed as an ontological reflection on the situatedness of human expression, its environmental constitution. Reading poetry alongside William Franke's thoughts on apophasis, this chapter elaborates on a more than coincidental alliance between ecology and apophasis.