Knowledge representation in a multi-layered database includes systems and methods for storing and retrieving data in the multi-layered database. The multi-layered database includes an object database layer that stores objects corresponding to real world entities and each object is associated with object properties, object relationships, and relationship properties. Underlying the object database layer is a graph database layer that stores nodes, node properties associated with the nodes, edges, and edge properties associated with the edges, wherein the nodes correspond to objects, node properties are indicative of the object properties, the edges are indicative of the object relationships, and the edge properties are indicative of the relationship properties of the object. Further, underlying the graph database layer is a backend database layer that stores corresponding data and metadata. Data can be stored and retrieved from the multi-layered database by composing and decomposing information between layers.