There is a glaring gap in the psychiatric literature concerning the nature of psychiatric symptoms and signs, and a corresponding lack of epistemological discussion of psycho-diagnostic interviewing. Contemporary clinical neuroscience heavily relies on the use of fully structured interviews that are historically rooted in logical positivism and behaviorism. These theoretical approaches marked decisively the so-called "operational revolution in psychiatry" leading to the creation of DSM-III. This paper attempts to examine the theoretical assumptions that underlie the use of a fully structured psychiatric interview. We address the ontological status of pathological experience, the notions of symptom, sign, prototype and Gestalt, and the necessary second-person processes which are involved in converting the patient's experience (originally lived in the first-person perspective) into an "objective" (third person), actionable format, used for classification, treatment, and research. Our central thesis is that psychiatry targets the phenomena of consciousness, which, unlike somatic symptoms and signs, cannot be grasped on the analogy with material thing-like objects. We claim that in order to perform faithful distinctions in this particular domain, we need a more adequate approach, that is, an approach that is guided by phenomenologically informed considerations. Our theoretical discussion draws upon clinical examples derived from structured and semi-structured interviews. We conclude that fully structured interview is neither theoretically adequate nor practically valid in obtaining psycho-diagnostic information. Failure to address these basic issues may have contributed to the current state of malaise in the study of psychopathology.