Guided by a series of associations of the word Ding in Adelung’s dictionary (1774/93) with metaphysical concepts and conceptualization, this entry explores how Goethe creatively appropriated the lexeme across a long trajectory of diverse textual practices. In light of the writer’s famously unsystematic approach to metaphysical problems, it focuses on scientific and literary works, as well as key autobiographical documents, in order to trace the meandering course of his ontological thinking as it developed into a morphologically informed cosmological reconstruction of the real. Through the transformative power of metaphor in his plays and poetry, in particular, as well as through scattered reflections in letters, conversations, and travel accounts, Goethe ultimately constructed a “metaphysics of appearances” (Metaphysik der Erscheinungen) that would link certain incorporeal generative ideas, including the primal plant (Urpflanze) and the no-thing (Unding), to their corporeal manifestations. In order to frame readings of Goethe’s metaphorical cosmography as staged in the verse play Satyros, oder der vergötterte Waldteufel (1773/1817; Satyros, or the Deified Forest God) and the world-theater Faust (1809, 1832), sections 2–4 present his morphological ontology—in response to Kantian dualism—as a dualistic monism. In this context the Ding/Unding dyad is explored as the basic unit of Goethe’s ontological thinking, which refuses to privilege one of its opposing terms over the other. By reconstructing things and thingness as the intractable problem of these two mutually exclusive concepts, Goethe offers opportunities for their further philosophical reflection. Section 2 begins with a discussion of Goethe’s conversation with Friedrich Wilhelm Riemer about Kant’s thing-in-itself—not as something real, but as an instrumentality of thought marking the unbridgeable gap between noumenal and phenomenal things. By contrast, his own dualistic monism suggests that (1) there is only a single dynamic universe of things and (2) in the process of its becoming each corporeal thing must be evaluated in relation to (a) all the other corporeal things in its midst and (b) the series of ontological modes, or the kinds of incorporeal things, that constitute the vector of its completion. To analyze these propositions, section 3 focuses on Goethean science, which equipped the investigator with “the eye of the mind” to see through to the essential reality of such dynamic things as optical, chromatic, and botanical phenomena in the otherwise invisible process of their formation. Section 4 then completes the preparatory framing by considering Goethe’s meditation about the ontological status of his Urpflanze (primal plant) in the anecdote “Glückliches Ereignis” (1817; Felicitous Event). Guided by this autobiographical account of his inaugural meeting with Friedrich Schiller, which configures their seminal friendship as an antipodal relationship, we can describe Goethe’s morphological ontology as a dualistic thing-monism that relies on essential polarities to sustain its non-reductive dynamism. With this complication of Goethe’s ontological point-of-view in mind, section 4 concludes by considering Ding in some letters that further connect it with Spinoza’s scientia intuitiva, which as the highest of three gradations of knowledge is adequate to the essence of things. Unlike Spinoza, however, whose geometrical method relies on the power of reason to build an ethically grounded epistemology, Goethe enlists the powers of the poetic imagination to construct a morphological ontology that is grounded in the power of negation. In this context section 5 offers readings of critical passages in Satyros and Faust that locate things on the vertiginous cosmological stage of perpetual becoming. And as section 6 argues in conclusion, the informing figures of thought in these works, including the void, allow us to situate Goethe’s Ding/Unding dyad within a lineage of philosophical and theoretical exploration that includes Heidegger’s late meditations on “Dingheit” (thingness) and “Leere” (void), as well conceptual innovations like the “virtual” in Gilles Deleuze’s transcendental materialism and the “incorporeal” in Elizabeth Grosz’s problem-oriented ontology.