Geography is the "G" in GIS and we can trace GIS back to classical geographical
problems that have motivated scientists for more than three centuries.
Von Thünen's models to describe the land use practices radiating out from
a central market location are still important in spatial studies where
transportation costs have an influence over decisions on land use. Dr.
Snow is widely regarded as the father of modern epidemiology, and Ian
McHarg's overlay method developed in landscape ecology has become a standard
operation in GIS software. All of these scientists used spatial thinking
to solve a problem and we can learn many lessons from their efforts.
In a more general sense we observe that geospatial thinkers - and practitioners,
those wanting to operationalise their thoughts and take action - are concerned
with the influence of multiple factors that all converge on a particular
space. In this sense, location is the unit of integration and given the
number of factors involved it is not surprising that every location is
unique. The geospatial analyst tries to tease out the different effects
to better understand the problem - all the time working with inherent
conceptual and mathematical constraints in the recording and handling
of digital geospatial data.