Description/Abstract: The field of psychology has operated since its modern foundation with an unresolved structural problem: the mind cannot be observed without the observation contaminating the result. Every methodology in the current compendium — self-report instruments, controlled experiments, observational studies, double-blind designs — is subject to some form of observation contamination. This paper presents an alternative methodology, termed the Interior Method, which approaches psychological observation from inside the subject's perceptual framework rather than from the researcher's exterior perspective. Rather than observing the mind from outside (and thereby contaminating the observation), the Interior Method presents the mind with specifically designed informational inputs and reads the mind's natural, uncontaminated response as the diagnostic data. The method operates on an established principle: the human mind behaves in structured and predictable ways when presented with information that alters the perceived reality of the perceiver. By designing the informational input (the data point) while controlling the metadata (the subject's awareness of being tested), the researcher obtains clean psychological data without observation contamination. The companion paper, "The Universal Diagnostic" (Randolph, 2026d), constitutes the first full demonstration of the Interior Method. The present paper extracts the general methodology and presents it as a universal framework applicable to any domain of psychological inquiry — cognitive bias, personality assessment, clinical diagnosis, developmental psychology, social cognition, and any other area where the observation problem has historically compromised research quality. The paper further identifies the specific three-layer mechanism by which the Dunning-Kruger effect operates at the highest cognitive level in physics, constituting the most precisely anatomized compendium edge in the literature. Keywords: psychology methodology, observation contamination, cognitive bias, Dunning-Kruger effect, Interior Method, replication crisis, psychological assessment, uncontaminated measurement, self-administering diagnostic, clinical assessment, information processing
Lucian Randolph (Sun,) studied this question.