Teaching and misteaching measurement in psychology

“Do not block the way to enquiry.”—Charles Sanders PierceA feature common to all scientific methods is critical enquiry, that is, testing claims. If the teaching of methods in any scientific discipline fails to exemplify this common feature, then the enterprise of science may be subverted. This could happen, for example, if a hypothesis fundamental to some method were not taught critically or, more seriously, if critical scrutiny of it were to be systematically excluded from the curriculum. It is argued here that this has happened in psychometrics with regard to the claim upon which psychological measurement depends, namely, that psychological attributes (e.g., intellectual abilities, personality traits, and social attitudes) are quantitative. It is further argued that this has happened because of historical and social pressures within the discipline. Suggestions are made for additions to the measurement curriculum.