El mètode objectiu

The author critiques pure introspective psychology for producing detailed descriptions of mental states without revealing their causal conditions, and advocates an objective method that links psychic phenomena to physiological processes. He surveys competing theories and debates such as parallelism versus determinism, highlights how associative and logical sequences observed introspectively fall short of causal explanation, and argues for applying the causal criteria of the physical sciences to psycho‑physiological succession. The work recommends experimental and physiological investigation to identify determining conditions and examines consequences for attention, association, and the study of lower forms of mental life.