6 - The status of psychophysical measurement

Summary

You will not find the boundaries of psyche by travelling in any direction, so deep is the measure of it.

(Heraclitus)

The scientific experimenter … need not be in the least concerned with methodology as a body of general principles.

(Sir Frederic Bartlett)

If what Kuhn (1970) said about the way that science works is correct, then the fuse lit by Campbell and Nagel was in danger of being snuffed out. Quantitative psychologists now possessed a paradigm of measurement, one almost universally accepted throughout the discipline. This was that standardised psychological procedures for making numerical assignments yield measurements. The strength of this paradigm was not just that it sustained a thriving ‘normal science’ (in Kuhn's sense), but equally important, it would never meet with any ‘anomalies’ or unsolvable puzzles. Because every situation involves quantity and number (i.e., there are always aggregates to count), numerical assignment procedures can always be contrived for any psychological attribute. Furthermore, cases of genuine measurement, should they ever arise in psychology, could also be thought to fit this paradigm. It stood almost invulnerable.

The fact that relative to the classical paradigm, or even Nagel's representationalism, quantitative psychology's modus operandi was itself an anomaly, could be ignored by an established science of psychology, one securely located within the university system, with its own journals and research conventions, attached to an expanding profession.