The Structure of WholenessUsing a part-whole calculation the vague concept of wholeness is rendered exactly like the structure of an atomic Boolean lattice. The prototypical structure of the whole thus defined has the status of a category, since each element of our experience can be considered as its desired application. This will be illustrated using examples from different ontological fields. The hypothetical and therefore fallible character of the structure is shown in its inadequacy in grasping quantum logical facts. This requires a differentiation of the totality. The defined structure can be seen as circular in two respects: on the one hand it is the precondition for understanding its own syntactic and semantic bases, on the other hand there is a mutual definability between its atoms, which leads us to the thesis that totality cannot be defined in a non-circular way. Introduction In this article I seek both to explain the popular, but vague, notion of totality and to highlight its significance for ontology. To begin with, I will give a brief overview of the essential elements: in accordance with an elementary intuition of "wholeness", I introduce an implicit axiomatic definition of its structure, which turns out to be a familiar Boolean lattice. This internal view of the concept of totality is followed by a more philosophical external view, which looks at the structure in its context. It will be shown that the structure corresponds to the criteria of an ontological category, i.e. consistency, adequacy, content and coherence, so we are justified in speaking of the 'category of totality'. This feature leads to some interesting results: as a consequence of the adequacy of a category the structure turns out to be a model in its own right. Self-application leads at the level of the axioms to the Boolean lattice of all substructures and at the level of the terms of the axioms to the semantic Boolean lattices, which can be seen as fundamental units for the entire language. Therefore, understanding the structure of "totality" takes it for granted that there is a pre-understanding of it. Furthermore, there is another type of circular understanding at the level of the atoms of the structure, because there is a mutual definability between the atoms, which cannot be eliminated without leaving the totality. But even if we try to leave it, we enter another totality, so that circularity is ultimately inevitable.A. Intuition First of all, let me describe the main intuition of "completeness".’.