The article highlights basic neuropsychological concepts of linguistic functioning, developmental and evolutional problems of language capacity and the cooperation of hemispheres in man. While the right hemisphere gathers impressions of the notions of things, the left hemisphere forms and uses abstract concepts. Primates can learn to communicate via symbols. Dyslexic children often have problems with ways of teaching that mainly use abstractions. Finally, the specific supply of concepts in both hemispheres is in part responsible for the very personality of a given individual.