One’s axioms are introduced at the beginning of one’s book and then all of the subsequent theorems are derived from the axioms. For example, Euclid claimed that, given a line and a point not on the line, there exists a unique line that passes through the point and is parallel to the given line. Lobachevski asserted that there is more than one parallel and Reimann that there are none. Thus, there are three geometries and, similarly, there may be more than one economics. I am, however, the only economist to ever precisely state my axioms and to base an entire theory on exactly those axioms and on nothing else.

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A Non-Mathematical Explanation of the Axioms
Do you call it total nonsense that Euclid assumed that, given a line and a point not on the line, there exists a unique line that passes through the point and is parallel to the given line?

Do you call it total nonsense that Lobachevski assumed that, given a line and a point not on the line, there exists many lines that passes through the point and are parallel to the given line?

Do you call it total nonsense that Reimann assumed that, given a line and a point not on the line, there exists no line that passes through the point and is parallel to the given line?