 The movements involved here are so-called “violent” movements, as opposed to “natural” ones discussed below. Avempace sketches a theory of dynamics based on a notion of “power” different from the Aristotelian notion of dynamis: they are mechanical forces which can join another force or counteract it by offering resistance. Shlomoh Pines introduced the term  “dynamics”[20]  to define his views, which no doubt were influenced by the tradition linked to John Philoponus (d. ca.  566).[21]  There is a minimum amount of moving power for each movable. For instance, to move a boat a minimum of power is needed, otherwise “one grain of sand could move the boat” (IB-SS-fakhry: 112.27).