Although the concept of force predates Newton 's law , there was no mathematical definition of force before Newton . The principle of least action ( or principle of stationary action ) , Schroedinger equation , Heisenberg uncertainty principle , causality and a few other laws also fall into this category ( of mathematical definitions ) . Some `` scientific laws '' appear to be mathematical definitions ( e.g. , Newton 's Second law F = , or the uncertainty principle , or the principle of least action , or causality ) .