Origin of meta-symbols: Navigation and point logic

Animal navigation based on local landmark is here expressed by a topological system consisting of point logic and open logic. Because disjunction of points is inconsistent with conjunction of opens, directed disjunction is introduced to improve the inconsistency. Choosing a directed set implies that a set of particular landmarks are mixed with up and they are regarded as one mass as a territory. It is nothing but an origin of a meta-symbol and/or familiar territory.