Concept structure and dichotomous measurement are logically separate issues

Evidence

A common claim is that a concept is really dichotomous, for example, many feel democracy has this characteristic. These two positions frequently go together, a necessary and sufficient condition and a dichotomous view of the object (e.g., Przeworski et al. 2000 on democracy). However, since I am not using a classic, Aristotelian logic, but a fuzzy one, I shall separate the issue of dichotomous concepts from their structure, which may or may not invoke the necessary and sufficient condition principle. Throughout this volume I shall assume that dimensions are continuous, and that a dichotomous dimension is just a special case. — Gary Goertz, Social Science Concepts, 203

Categorization

• XREF: Przeworski et al. 2000 on democracy is the classic dichotomous-democracy target; connects to debates over democratization measurement.