Seeing Doing and Knowing is an original and comprehensive philosophical treatment of sense perception as it is currently investigated by cognitive neuroscientists. Its central theme is the task-oriented specialization of sensory systems across the biological domain; these systems coevolve with an organism''s learning and action systems providing the latter with classifications of external objects in terms of sensory categories purpose--built for their need. On the basis of this central idea Matthen presents novel theories of perceptual similarity content and realism. His work will be a stimulating resource for a wide range of scholars and students across philosophy and psychology.