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  "body": "\n## Summary\n\nOrdered geometry is the part of geometry that uses only points, lines and the relation of [[betweenness|CE8GX6ADZS]], with no notion of distance, angle or parallel.\nIts axioms are the axioms of incidence and order, including [[Pasch's axiom|KJT98G16Y4]].\nIt is common to [[Euclidean geometry|KRZD96GSVC]], [[absolute geometry|VKFPCSRNDH]], hyperbolic geometry and affine geometry over ordered fields.\nSegments, rays, half-planes, convex sets and the inside of a triangle all belong to it.\n\n## Explanations\n\n### L1 human\n\nOrdered geometry asks what one can say about a drawing if one may not measure anything.\nOne can still say which point lies between which, which side of a line a point is on, and whether a figure is convex.\nFor example, \"the two diagonals of a convex quadrilateral cross each other\" is a fact of ordered geometry.\n",
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