Isness: A Structural Primitive Prior to Existence

Every domain-specific account of existence presupposes something that cannot be supplied from within that domain: a structural condition prior to any domain-specific mode of existence. This paper introduces isness as that condition and argues for three features: (1) its self-confirming character — no operation can remove isness without the removal itself having isness; (2) its role as the structural medium in which any appearing occurs, prior to any formal or ontological framework; and (3) its priority to the subject-object distinction — isness is presupposed by both idealism and realism. The paper situates isness relative to the Fregean tradition, Meinong's theory of objects, Quine's ontological criterion, Heidegger's ontological difference, and the contemporary grounding literature (Fine, Schaffer, Rosen), arguing that isness is prior to each.