18.09.2011 
Topography - Reality - Cognition [Voser 
2001] 
A) The solid and liquid earth bounded by the physical 
earth's surface, or topographic surface, which 
is the surface which we see, on which we stand, walk, drive, and, occasionally, swim. It is highly 
irregular, even after some obvious smoothing which is always necessary to make it a smooth 
surface amenable to mathematical treatment, and also after some averaging with respect to time 
since this surface undergoes temporal variations (on the order of decimeter or more) because of 
tidal effects, etc.