Concept structures can mix necessary conditions with family resemblance across levels.

Evidence

While the most common practice by far is to use the same aggregation rule for all attributes at a given level, one should always keep the possibility of hybrid structures in mind. In a variety of settings I think that hybrid structures are very good ideas for doing ideal type conceptualization. For example, one could easily have a number of necessary conditions for a low level of democracy and then have a variety of conditions that work in family resemblance style to get to higher levels of democracy. — Gary Goertz, Social Science Concepts and Measurement, 1069

Categorization

• XREF: Echoes Wittgenstein-family-resemblance arguments in Along the Archival Grain’s discussion of colonial racial categories built flexibly, not by fixed criteria.