Throughout this essay it has been necessary to engage in a running fight with what may be called a positivistic conception, or rather misconception, of history, as the study of successive events lying in a dead past, events to be understood as the scientist understands natural events, by classifying them and establishing relations between the classes thus defined...
To speak of the psychology of reasoning, or the psychology of the moral self (to quote the titles of two well-known books), is to misuse words and confuse issues, ascribing to a quasi-naturalistic science a subject-matter whose being and development are not natural but historical. But if psychology avoids this danger and renounces interference with what is properly the subject-matter of history, it is likely to fall back into a pure science of nature and to become a mere branch of physiology, dealing with muscular and nervous movements.
But there is a third alternative. In realizing its own rationality, mind also realizes the presence in itself of elements that are not rational... These irrational elements are the subject-matter of psychology... sensation as distinct from thought, feelings as distinct from conceptions, appetite as distinct from will...
