the old maps we clutch

The ordinary consciousness, that of scientific popularizers and on down the demographic rungs-- see the unknown, like on an old map, as a separate area, separate from the continents of knowledge. But is it? Can it be, so delimited, if we do not know it, and why else call it the unknown, -- so how can we say, how can we point on the map, under the dragon? 

In fact there is evidence to suggest the unknown surrounds and interpenetrates us constantly. Rather than terra incognita, should we be saying, usus incognitus?