Status Updates From La meccanica nel suo svilup...

"A rule, reached by the obsevation of the facts, cannot possibly embrace the entire fact, in all its infinite wealth, in all its inexhaustable manifoldness; on the contrary, it can furnish only a rough outline of the fact, one-sidedly emphasising the feature that is of importance for the given technical (or scientific) aim in view."
-Ernst Mach

It's my first time to know how the level equilibrium formed