On the Meaning of Psychological Concepts: Is There Still a Need for Psychological Concepts in the Empirical Sciences?

When empirical psychology mostly focuses on physiological processes and external behavior that have their own concepts, the meaning of psychological concepts becomes obscure. If there are only physical processes and external behavior, then why are psychological concepts needed in the empirical sciences? Since the late 19th century, empirical psychologists and cognitive scientists have argued that introspective information about normal psychological processes is not reliable. Furthermore, many philosophers consider that the physicalist theory of mind is true, which would imply that psychological concepts are only words without explanatory power. However, without introspection, we would not be able to form concepts about other minds and psychological phenomena and understand the psychological states of other people or animals. The meaning of a psychological concept is neither its use for external behavior nor language use in context.