The Initiative also approached Human Capacity from the outside in: instead of beginning with internal psychology, it asked what recurrent functional requirements appear across human life.

The result was a provisional architecture of 13 domains. The word provisional matters. These domains are discovery-stage candidates generated by converging literatures and dependency/recovery evidence. Many overlap strongly with established ICF, WHODAS and ADL/IADL domains, but current science does not establish that 13 is an irreducible or exhaustive structure. The architecture is meant to be validated, challenged, split, merged or extended.

What makes the domains useful is the distinction between a requirement and an implementation. Human beings need material resources, but paid employment is not a universal functional requirement. People need environmental access, but driving is only one culturally and technologically specific way of achieving it. People need nutritional provision, but they do not all need to grow, purchase or prepare food personally.

The domains therefore describe recurring areas in which something has to be sufficiently provided. The person may provide it directly, coordinate others, use technology, rely on institutions, or receive support.

That makes the domains a natural organizing layer for the website. Each one can ask the same set of scientific questions: What is required here? What capacities help a person participate in managing it? How do those capacities develop? What does the environment change? What do other people and institutions provide? What is expected of the person? What consequences do they actually bear? And how can any of this be measured?

The 13-domain proposal has substantial external convergence. ICF covers learning, communication, mobility, self-care, domestic life, relationships, major life areas and community/civic life; WHODAS covers cognition, mobility, self-care, getting along, life activities and participation; IADL measures commonly include food preparation, housekeeping, transport, medication and finance. This convergence supports the territory. It does not yet validate the exact number, boundaries or hierarchy of the proposed domains.