The Law of Natural Numbers

  • Michael Elazar
Part of the Boston Studies in the Philosophy of Science book series (BSPS, volume 288)


Having excluded every possible external cause for free fall, while establishing impetus as a necessary inner cause, Fabri proceeds to develop his “natural numbers” law – that in each successive (equal) amount of time a falling body passes a distance which is one unit bigger than its immediate predecessor, i.e. according to the simple series 1, 2, 3, 4, 5 etc. This chapter outlines the way Fabri develops his “discrete” rule – a mirror image of Galileo’s continuous analysis – by employing impetus and adopting Galileo’s Archimedean-style “infrastructure”, that discards levity and allows for motion in the void.


Arithmetical Progression Free Fall Natural Motion Uniform Motion Heavy Body 
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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Max Planck Institute for the History of ScienceBerlinGermany

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