The category mistake as philosophical error
A category mistake presents facts belonging to one logical type as if they belonged to another. Ryle's example is a visitor who tours Oxford's colleges, libraries and laboratories and then asks where the University is, treating the University as one more building alongside them rather than as the way those buildings are organized. Dualism makes the same error: it treats 'mind' as a further thing next to the body instead of as a description of how the body's activities are organized.
