Incidence Relations in the Plane
and in Space

Incidence relations come in two distinct kinds. In the first kind we start with some simple geometric objects and we look for another which is determined by the given objects. An example of this kind is the most basic of the incidence axioms of planar geometry. The other kind specifies the intersection of geometric objects. The easiest example of this is the other basic incidence relation of planar geometry.

Incidence relations in space.

In space we have points and lines, just as in the plane, but we also have a lot of planes. As a result there are a lot more incidence relations. We will simply list them here. First the "determining" relations. Next the intersection relations.

Return to Basic information about spheres.
Go to incidence on the sphere.
Table of Contents.
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