When it comes to communicating between individuals, tools that go beyond the diversity of individual perceptions need to appear, otherwise there is no communication. There is thus an abstraction process that is part of the cognitive development of the human subject through which individual entities are grouped into classes according to similar, pertinent, repetitive features. Communication is only possible thanks to a coding of concepts in signs, this coding being, in the case of human beings, language. This clearly shows the role of concepts, which functions as a turntable, ensuring the transition from the perception of reality to the infinity of its aspects of communication through a limited inventory of ordered signs in a system.
