20120711

Newton: Hypothesize no Attraction


By now, readers will realize that gravitation is a push, not a pull. That is not, of course, what Newton is known for. He always gets blamed by indeterminists as their “attraction man” or the guy who proposed “action-at-a-distance.” He is also used as the man who said “hypotheses non fingo” (I propose no hypotheses). Nevertheless, Newton is known for plenty of hypotheses, with his mathematical explanation of gravitation being particularly hypothesis-laden. We saw in a previous post that Newton actually proposed a push theory (http://thescientificworldview.blogspot.com/2012/05/neomechanical-gravitation-theory.html). Thanks to astute reader Ron Davis, who just sent me these quotes from Newton, which state his position on attraction:


DEFINITION VIII

           ..."I likewise call attractions and impulses, in the same sense, accelerative, and motive; and use the words attraction, impulse, or propensity of any sort towards a center, promiscuously, and indifferently, one for another; considering those forces not physically, but mathematically; wherefore the reader is not to imagine that by those words I anywhere take upon me to define the kind, or the manner of any action, the causes or the physical reason thereof, or that I attribute forces, in a true and physical sense, to certain centres (which are only mathematical points); when at any time I happen to speak of centres as attracting, or as endued with attractive powers."  From direct Latin to English translation of Mathematical Principles of Natural Philosophy: Sir Isaac Newton 
            
SECTION  XI

THE MOTIONS OF BODIES TENDING TO EACH OTHER WITH CENTRIPETAL FORCES
    "I have hitherto been treating of the attractions of bodies towards an immovable centre; though very probably there is no such thing existent in nature.  For attractions are made towards bodies, and the actions of the bodies attracted and attracting are always reciprocal and equal by Law III; so that if their are two bodies, neither the attracted not the attracting body is truly at rest, but both (by Cor., IV  of the Laws of Motion), being as it were mutually attracted, revolve about a common centre of gravity.  And if there be more bodies, which either are attracted by one body, which is attracted by them again, or which all attract each other mutually, these bodies will be so moved among themselves, that their common centre of gravity will either be at rest, or move uniformly forwards in a right line.  I shall therefore at present go on to treat of the motion of bodies attracting each other; considering the centripetal forces attractions; though perhaps in a physical strictness they may be more truly be called impulses.  But these Propositions are to be considered as purely mathematical; and therefore, laying aside all physical considerations, I make use of a familiar way of speaking, to make myself the more easily understood by a mathematical reader."  The Mathematical Principles of Natural Philosophy, Newton.


Although his confusion is reflected in his ambivalence and over-worked erudition, Newton does not really come down on the side of attraction. This is despite his mystifying “centripetal impulse” comment. So why do most folks and most regressive physicists cherry-pick Newton in favour attraction? Attraction is consupponible with a slew of indeterministic assumptions. The “centripetal impulse” is akin to freewill and the view that humans are not subject to the Principle of Least Action” of mechanics. You could go through "The Ten Assumptions of Science," finding that each of them contradicts the hypothesis of attraction. It is nice to know that Newton really didn’t believe it himself.

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