Symbolic borders, sometimes called conceptual or abstract borders, are borders on the plane of the mental or metaphorical landscape. They can also be described as differences, understood as being regulated by spatial metaphors of crossing, inside/outside, etc. They are the conditions of manifestation of topographic borders.
Symbolic borders are very important in border poetics, where they figure as the major binary oppositions or limit values (poor/rich, female/male, black/white, English/French, private/public, etc.) which structure the world of the literary text. This means they are usually conceived of as being represented borders, rather than borders of the representation.
Other types of border can be viewed as sub-sets of symbolic borders. Thus temporal borders can be seen as symbolic oppositions between different periods of time, the epistemological border can be seen as the symbolic opposition between the known and the unknown, and textual borders can be seen as the borders between text and non-text, or between different styles. See Topographic border for an argument for calling also topographic borders symbolic.