Arnold Pick (1851-1924) provided the first description of the neurodegenerative disease associated with his name; but his importance to the field of neuroscience goes far beyond this eponymous gift. His view that the process of dementia should be seen as a mosaic of circumscribed neuropsychological deficits and not as a diffuse degradation of mental abilities is essential for progress in a cognitive neuropsychological approach to the study of dementias.