Unity of Composition

[A] stratum does indeed have a unity of composition, which is what allows it to be called a stratum: molecular materials, substantial elements, and formal relations or traits. [TP: 49]

We may therefore use the term central layer, or central ring, for the following aggregate comprising the unity of composition of a stratum: exterior molecular materials, interior substantial elements, and the limit or membrane conveying the formal relations. [TP: 50]

The limit between them is the membrane that regulates the exchanges and transformation in organization (in other words, the distributions interior to the stratum) and that defines all of the stratum's formal relations or traits [TP: 50]

There is a single abstract machine that is enveloped by the stratum and constitutes its unity. This is the Ecumenon, as opposed to the Planomenon of the plane of consistency. [TP: 50]

A stratum, considered from the standpoint of its unity of composition, therefore exists only in its substantial epistrata, which shatter its continuity, fragment its ring, and break it down into gradations. The central ring does not exist independently of a periphery that forms a new center, reacts back upon the first center, and in turn gives forth discontinuous epistrata. [TP: 50-1]

[T]he organic stratum does have a specific unity of composition, a single abstract Animal, a single machine embedded in the stratum, and presents everywhere the same molecular materials, the same elements or anatomical components of organs, the same formal connections. Organic forms are nevertheless different from one another, as are organs, compound substances, and molecules. [TP: 45-6]

A given stratum retains a unity of composition in spite of the diversity in its organization and development. The unity of composition relates to formal traits common to all of the forms or codes of a stratum, and to substantial elements, materials common to all of the stratum's substances or milieus. [TP: 502]