ageGradeCount
plain-language theorem explainer
ageGradeCount fixes the number of universal age grades at five within the Recognition Science anthropology module. Cross-cultural researchers and anthropologists would cite the constant when modeling the five life stages observed in most societies. The definition is a direct constant assignment with no computation or lemmas required.
Claim. The number of universal age grades in human societies is $5$.
background
Age-grading systems divide the human lifespan into childhood (0-12 yr), adolescence (12-20 yr), adulthood (20-45 yr), middle age (45-65 yr), and old age (65+ yr). The module states that Recognition Science predicts exactly five grades because configDim D equals 5, the same template that yields five Big Five personality factors, five Köppen climate zones, five sleep stages, five social strata, and five hurricane categories. Adjacent-grade life-span ratios scale near φ, with the childhood-to-adolescence ratio approximately 1.67.
proof idea
The definition is a direct constant assignment of the natural number 5 with no lemmas applied.
why it matters
This definition supplies the grade count for the downstream AgeGradingCert structure and the theorems ageGradeCount_eq and ageGradeCount_pos. It implements the structural claim that five age grades are forced by configDim D = 5, consistent with self-similar scaling and the eight-tick octave in the Recognition framework. The module supplies an explicit falsifier: any ethnographic survey of at least 100 cultures showing a modal count reliably different from 5 ± 1.
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