Download Axioms for Absolute Geometry

Euclidean and Non-Euclidean Geometry – Fall 2007
Dr. Hamblin
Axioms for Absolute Geometry
Our axioms for absolute geometry are listed here. As we proceed through the course, we will add to
this list.
Incidence Axioms
Our first axioms govern how points, lines, and planes interact.
I-1.
Each two distinct points determine a line.
I-2.
Three noncollinear points determine a plane.
I-3.
If two points lie in a plane, then any line containing those two points lies in that plane.
I-4.
If two distinct planes meet, their intersection is a line.
I-5.
Space consists of at least four noncoplanar points, and contains three noncollinear points.
Each plane is a set of points of which at least three are noncollinear, and each line is a set of
at least two distinct points.