problem-set/geometry/tarski/t7.desc created : 07/16/86 revised : 08/17/89 Natural Language Description : Theorem 7: For all pairs of distinct points y and z, if w and x are on the line yz to the left of y (i.e. not between y and z), then either w is betweeen x and y or x is between w and y. Versions : NOTE: all versions use a weighting scheme in which variables (and skolem functions) are weighted high and constants low. t7.ver1 : Original formulation of the axioms, from McCharen, Overbeek, & Wos [Aug. 1976]; uses hyperresolution, UR resolution, and unit deletion. created : 07/16/86. verified for ITP : Untested. translated for OTTER by : caw. verified for OTTER : 07/20/89. t7.ver2 : Reformulation of the axioms, from Quaife [JAR 5 (1989)]. created : 07/25/89. verified for ITP : Untested. translated for OTTER by : caw. verified for OTTER : no proof. t7.ver3 : Reformulation of the axioms, from Quaife [JAR 5 (1989)]. created : 07/25/89. verified for ITP : Untested. translated for OTTER by : caw. verified for OTTER : no proof.