This chapter brings together some of the main themes that run through the previous chapters, namely: the etiological-environmental individuation of cognitive kinds; the advantages of a real-kind approach to cognitive ontology; and the purview of cognitive neuroscience. On the first score, I distinguish the variety of externalism defended in this book from the familiar varieties in the philosophical literature. On the second, I show how taxonomic practices in cognitive science can benefit from reflecting on the overarching ontological categories in the cognitive domain and from greater clarity in distinguishing relationships among different kinds of kinds (for example, subordinate and superordinate kinds). On the third point, I argue that the scientific discipline of cognitive neuroscience, which aims to build bridges between neural and cognitive taxonomies, need not revolve around the search for neural correlates of cognitive kinds.

Psychiatric diagnosis and research is hampered by problems in nosological classification. Recent development has seen the suggestion of dimensionally-based classification systems like the Research Domain Criteria (RDoC) and cognitive ontology (CO), with the latter being developed by Bilder in his chapter. I here discuss some usually tacit or implicit presuppositions of CO concerning brain and mind. I conclude that, despite shifting from an entity-based approach (as in the DSM) to a dimensional approach, the cognitive ontology project still encounters the problem of connecting neuronal changes to psychopathological symptoms and, more generally, brain and mind.