Going round in squares: Theory-based measurement requires a theory of measurement

In their article on theory-based measurement, Borgstede and Eggert (2023) argue that a substantive formal psychological theory that is capable of predicting expected measurement outcomes for the theoretical objects of measurement it posits to exist is both necessary and sufficient for psychological measurement. They reveal that measurement in psychology mostly concerns the estimation of latent variables and compares unfavorably to the development of measurement in the history of physics. They, however, fail to include a comparison with the great advances in theory-based measurement achieved in modern physics. In this commentary, I describe how measurement is formalized in classical physics and examine what would be required to formalize the physical measurement of psychological phenomena. I conclude that, without an examination of the theoretical assumptions underlying current measurement procedures and a formal notion of psychological measurement, it is unlikely that psychological science will be able to generate the substantive theories suggested by Borgstede and Eggert.