A concept is defined as an abstract idea. It is understood to be a fundamental building block underlying principles, thoughts and beliefs.Concepts play an important role in all aspects of cognition. As such, concepts are studied within such disciplines as linguistics, psychology, and philosophy, and these disciplines are interested in the logical and psychological structure of concepts, and how they are put together to form thoughts and sentences. The study of concepts has served as an important flagship of an emerging interdisciplinary approach, cognitive science.
In contemporary philosophy, three understandings of a concept prevail:
- mental representations, such that a concept is an entity that exists in the mind (a mental object)
- abilities peculiar to cognitive agents (mental states)
- Fregean senses, abstract objects rather than a mental object or a mental state
Concepts are classified into a hierarchy, higher levels of which are termed "superordinate" and lower levels termed "subordinate".