include wearing a professional dress during business meetings, shaking hands to greet others in the West, or bowing to greet others in the East. A single symbol can carry multiple distinct meanings such that it provides multiple types of symbolic value. Paul Tillich Paul Tillich argued that, while signs are invented and forgotten, symbols are born and die. There are, therefore, dead and living symbols. A living symbol can reveal to an individual hidden levels of meaning and transcendent or religious realities. For Tillich a symbol always "points beyond itself" to something that is unquantifiable and mysterious; symbols open up the "depth dimension of reality itself". Symbols are complex, and their meanings can evolve as the individual or culture evolves. When a symbol loses its meaning and power for an individual or culture, it becomes a dead symbol. When a symbol becomes identified with the deeper reality to which it refers, it becomes idolatrous as the "symbol is taken for reality." The symbol itself is substituted for the deeper meaning it intends to convey. The unique nature of a symbol is that it gives access to deeper layers of reality which are otherwise inaccessible. Role of context in symbolism A symbol's meaning may be modified by various factors including popular usage, history, and contextual intent. Historical meaning The history of a symbol is one of many factors in determining a particular symbol's apparent meaning. Consequently, symbols with emotive power carry problems analogous to false etymologies. Context The context of a symbol may change its meaning. Similar five-pointed stars might signify a law enforcement officer or a member of the armed services, depending upon the uniform. Symbols in cartography Symbols are used in cartography to communicate geographical information (generally as point, line, or area features). As with other symbols, visual variables such as size, shape, orientation, texture, and pattern provide meaning to the symbol. According to semiotics, map symbols are "read" by map users when they make a connection between the graphic mark on the map (the sign), a general concept (the interpretant), and a particular feature of the real world (the referent''). Map symbols can thus be categorized by how they suggest this connection: Pictorial symbols (also "image", "iconic", or "replicative") appear as the real-world feature, although it is often in a generalized manner; e.g. a tree icon to represent a forest, or green denoting vegetation. Functional symbols (also "representational")