internal variance

Compiled with AI assistance and selectively reviewed. Please consult the cited passages; the books remain the authoritative source. About this companion

Editorial synthesis · provisional

Definition

Internal variance is McShea’s function-free notion of structural complexity as differentiation among parts, discussed as a precursor to the Zero-Force Evolutionary Law. It tracks differences or part types without deciding how well they work. RB1 uses nonadaptive examples to separate increasing variety from useful integration, so a larger internal variance is not automatically increased fitness, functional information or thermodynamic entropy.

Explanation

The direct paragraph attributes the term to McShea’s 2005 formulation and illustrates it through fence pickets acquiring different wear patterns and lunar surfaces accumulating craters. These examples are deliberately nonadaptive. The proposal preserves that illustrative status rather than treating a weathered fence as a reproducing organism or every new difference as a functional improvement.

The later formulation counts part types or degrees of differentiation independently of their functions. Variance-like models can express an average tendency toward divergence when relevant forces or constraints are absent. No new numerical index, normalization or measurement protocol is supplied here: the assessment retains the local conceptual measure and named theoretical genealogy.

RB1 then separates functional selection and organization from this background spread of difference, and rejects equating its level-relative variables with one entropy metric. AB similarly says functional information requires a specified function and possibility space. The proposed entry therefore does not substitute internal variance for an evaluation of viability, performance or organized retention.

Scope and attribution

Retain the nonfunctional measure, the native examples and their limited explanatory role.

RB1 — The Real Book, Volume I: The Possible Is Real

Differentiation among parts is explicitly divorced from function and adaptive explanation.

Occurrence locators: 224, 225, 226.

RB3 — The Real Book, Volume III: Murmurations

Variance-like differentiation supplies a null expectation distinct from goal-directed growth.

Occurrence locators: 41.

Background used in the editorial explanation

Named theories and mechanisms are distinguished from neighboring background, homonyms and the author’s own synthesis. Reproduced AI passages retain their separate voice.