CONCEPTS
At the very core of language is the symbol-concept association. The symbol by itself is just a visual or auditory pattern with little significance. But when paired with a concept, the symbol becomes a powerful currency for thought and communication.
So what is the concept? Basically it is knowledge--stored information. It can be a small body of information--just enough to recognize something; to let us know that we have experienced it before.
(See an original unedited quote by moses in the Graphic Version)