Philosophical perspectives on measurement

This chapter aims to present a brief conceptual history of philosophical thinking about measurement, concentrating in particular on the issues of objectivity and subjectivity, realism and nonrealism, and role of models in measurement, as well as a discussion of how these philosophical issues have shaped thinking and discourse about measurement in both the human and physical sciences. First, three perspectives on measurement and its epistemic status are discussed, grouped as (a) naive realism, (b) operationalism, and (c) representationalism. Following this, we discuss how these perspectives have informed thinking about the concept of validity in the human sciences, and how they have influenced the way in which measurement is characterized in different contexts as being dependent on empirical and/or mathematical constraints. We then attempt to synthesize these perspectives and propose a version of model-dependent realism which maintains some of the elements of each of these perspectives and at the same time rejects their most radical aspects, by acknowledging the fundamental role of models in measurement but also emphasizing that models are always models of something: the empirical components of measurement are designed and operated so as to guarantee that, via such models, measurement results convey information on the intended property. The analysis also provides a simple explanation of two of the most critical stereotypes that still affect measurement science: the hypotheses that (1) measurement is quantification, which hides the relevance of the empirical component of the process, and (2) measurement is only a process of transmission and presentation of preexisting information, usually intended as the “true value” of the measurand, which instead neglects the role of models in the process.