He had 5 postulates.
Originally Posted by peter eldergill
- You can draw a straight line from any point to any point
- you can continue a line to infinity
- you can contruct a circle with any center and any radius
- all right angles are equal to one another
- If a straight line falling on two straight lines make the interior angles on the same side less than two right angles, the two straight lines, if extended indefinitely, meet on the side on which are the angles less than two right angles.
None of these can be derived from the others.
People had been trying to derive the 5th from the others for millenia until it was shown that it couldn't be done by generating internally consistent geometries using other propositions
Reductionist and proud of it.
Being ignorant is not so much a shame, as being unwilling to learn. Benjamin Franklin
Chase after the truth like all hell and you'll free yourself, even though you never touch its coat tails. Clarence Darrow
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