Adding nonmonetary factors like rights breaks sum-based measurement approaches.

Evidence

This is exactly the sort of issue we have already seen when contrasting consumption concepts and measures of poverty with human well-being ones. Once one begins to include nonmonetary factors, such as rights, then staying within the sum approach to conceptualization and measurement becomes difficult. — Gary Goertz, Social Science Concepts and Measurement, 1453

Categorization

• DEFINE: Explains why the ‘sum’ concept structure has a built-in limit: it presumes commensurable, aggregable components.
• XREF: Echoes debates over multidimensional poverty indices (e.g., human well-being vs. consumption measures).