A river flows in one way rather than another because the particles that form the river have momentum one way rather than another. The reason they have this momentum is because the surfaces of the river interact with the air, obstacles, and the rock bed underneath it, and then pass on momentum to internal river particles, which pass on that momentum to other particles, etc. In this way, is the river not processing information regarding things it can directly "observe" about its environment at its surface, as well as the things it has experienced in the past, then processing that information deeper and deeper, until it ultimately leads to a decision on which way the river flows?