From: fortunati.luigi@gmail.com   
      
   Arm wrestling: initially, hand A pushing to the right and hand B pushing to   
   the left are still because the action and reaction are equal and opposite.   
      
   If the two opposing forces remained *always* equal (as Newton's third law   
   states), they would never start moving to the right or even to the left: they   
   would remain eternally still.   
      
   Ibex A and B fight horns against horns and are still because the action of   
   ibex A to the right is perfectly equal and opposite to the reaction of ibex B   
   to the left: how could they both start moving (accelerate) to the right or to   
   the left if neither of    
   the two forces prevailed over the other? They couldn't and they would remain   
   eternally still!   
      
   Team A pulls the rope to the right with the same force with which team B pulls   
   it to the left and they remain still until when? Until the balance of the two   
   opposing forces is broken and one of the two forces prevails.   
      
   The rope between the horse and the stone moves with uniform speed until the   
   force of the horse pulling to the right is equal and opposite to the friction   
   of the stone on the ground pulling to the left but when its speed increases   
   (acceleration) the force    
   of the horse cannot be equal to the resistance of friction!   
      
   In short, the perfect balance between action and reaction exists only when the   
   two bodies (together) are still or move with uniform and rectilinear speed but   
   not when they accelerate!   
      
   The young student who comes across this discussion will ask himself: are these   
   simple considerations right or wrong?   
      
   Since they are contrary to the teachings he receives, he should immediately   
   think that Newton is right and, therefore, that these considerations must be   
   easily contestable by those who know more.   
      
   But then he would also ask himself: how come the discussion ran aground   
   without anyone being able to refute it?   
      
   And the doubt would remain.   
      
   Luigi Fortunati   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)