Max Isserlin and the Role of Aphasiology in the Debate on Psychologism in Early Twentieth-Century Germany
What comes first, language or thought? Can we form concepts and ideas without drawing upon linguistic forms? Or, can we express ourselves verbally without previous conceptual intervention? These sort of questions have been long discussed in philosophy of mind and philosophy of language, but they also played an important role in the history of psychology. By the second decade of the twentieth century, a fascinating struggle between ‘pure’ philosophy and the newly emerging experimental psychology took place in Germany. It took many forms, but central to this problematic was the necessity of some psychologists to base knowledge and its justification in psychological laws, i.e. in naturalizing epistemology and logic. Detractors of such intentions can be found in many places, but one particular way of trying to keep philosophy and psychology apart was undertaken by some neurologists working in the pathology of language (aphasia).
The debate over aphasia in the German lands presented two seemingly irreconcilable views: on the one side, there were the holists, who saw the brain as a functioning whole. They disagreed with the classic localizers, who ascribed autonomous function to circumscribed areas of the cerebral cortex. This disagreement had important consequences not just for the understanding of aphasia but also for the understanding of the relation between language and thought. However, as the German psychiatrist and neurologist Max Isserlin (1879-1941) pointed out, these opposing views did have something in common; no matter what comes first, for most aphasiologists thought and language were functionally different and hence, must be studied independently. The new experimental psychology, especially the one labelled as thought-psychology (Denkpsychologie) had representatives, like Otto Binswanger, Arthur Kronfeld and Richard Hoenigswald, who believed that language could be completely reduced to thought and that aphasia and kindred disorders of speech could be therefore studied as paralogisms.
In this paper, I intend to put forward Isserlin’s defence of aphasiology as an empirical, psychologically based enterprise, which had to be different to any prescriptive theory of science and ‘pure’ philosophy. The pathology of language as conceived in the early twentieth century could, therefore, shed some new light on the relation of language and thought