  In his important summary of his dynamics – generally known by  its Latin title “Specimen Dynamicum” –  Leibniz distinguishes between two kinds of active force. The first,  and most important, is of course vis viva itself. In the  context of his physics, vis viva, or “living  force,” represents for Leibniz a measure of a body’s ability to bring about effects in virtue of its motion. It is an active force  which allows a moving body to, say, raise itself up to a given height or impart a motion to a slower body. (Intuitively, we might think of  it as the “force” that a bowling ball, for example, has  in virtue of its falling from some height, or the power a baseball  has once released from a pitcher’s hand.) As noted above, Leibniz  maintains that vis viva is conserved both locally in  particular cases of impact, and globally in the created world taken  as a whole. The living force a body expends in raising itself to a  given height must therefore be equal to the living force it gains by  falling from that height; the vis viva a body is able to  transfer to another body through impact must be equal to the  measurement of vis viva it loses during that   impact.[19] 