Graph Theory = Network Theory = the essence of all systems, all networks, artificial networks, articulations intelligence, machine learning, neural nets, etc etc etc.
Every node is a sensor, is an input, that is defined by the edges associating it to other nodes, and so on.
Networks are matrices. Matrices are compositions of two sets of objects, of nodes and edges, revealing where they intersect.
I feel if we understand Graph Theory, we will better understand information, and how it is encoded and processed.
Intelligence is nothing more than the an expression of engrams, of memory traces, of a system of networks, adapting to new inputs.