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Revision difference : point-free geometry
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Point-free geometry is based on the idea that in geometry it is not necessary to assume as a primitive the notion of point. Instead, we can start from the notion of a region in the space and the points are defined by suitable \textit{abstraction processes}, i.e. order-reversing sequences of regions. Firstly, such a question was analized by A. N. Whitehead in the books "An Inquiry Concerning the Principles of Natural Knowledge" and "The concept of Nature" in which the inclusion relation is a primitive. Successively in "Process and Reality" Whitehead proposed a new approach in which the connection relation is considered. Whitehead'analysis is philosophic in nature. Successively several autors translated this analysis into systems of axioms for a mathematical treatment of point-free geometry (see [1]). A very interesting proposal for a point-free approach to geometry is exposed in [2]. Point-free geometry is based on the idea that in geometry it is not necessary to assume as a primitive the notion of point. Instead, we can start from the notion of a region in the space and the points are defined by suitable \textit{abstraction processes}, i.e. order-reversing sequences of regions. Firstly, such a question was analized by A. N. Whitehead in the books "An Inquiry Concerning the Principles of Natural Knowledge" and "The concept of Nature" in which the inclusion relation is a primitive. Successively in "Process and Reality" Whitehead proposed a new approach in which the connection relation is considered.
\textbf{References} \textbf{References}
1. G. Gerla, Pointless geometries, in Handbook of Incidence Geometry, F. Buekenhout and W. Kantor (eds) 1994 North-Holland. 1. A. N. Whitehead, An Inquiry Concerning the Principles of Natural Knowledge, Cambr. Univ. Press, Cambrige 1919.
2. H. J. Schmidt, Axiomatic Characterization of Physical Geometry, Lecture Notes in Physics, Springer-Verlag, Berlin Heidelberg 1979. 2. A. N. Whitehead, The concept of Nature, Cambr. Univ. Press, Cambrige 1920.
3. A. N. Whitehead, An Inquiry Concerning the Principles of Natural Knowledge, Cambr. Univ. Press, Cambrige 1919. 3. A. N. Whitehead, Process and Reality, The Macmillan Co., New York 1929.
4. A. N. Whitehead, The concept of Nature, Cambr. Univ. Press, Cambrige 1920.
5. A. N. Whitehead, Process and Reality, The Macmillan Co., New York 1929.