Quadrimechanica Entropy: the basis of mechanics

Classical, Quantum, Relativistic and Statistical: the four branches of mechanics. However, the Quattro Donna of Physics disagree even about the entities that are supposed to be fundamental, such as space, matter and time. In order to search for an union, this contribution considers Indeterminacy in a Classical context and takes a path based on a division that could be named factual as opposed to the conventional approach of cause and effects. This sets back a primary division between "observable entities" and "measurable quantities". Recovering the primordial Classical experiment and describing the "Free Fall" in terms of distinct times - the relaxation time of the ("falling") 'light' bodies (m1, m2,...); the characteristic time of the 'heavy' (M) body and the rate of change of the mechanical system [M, m1, m2, ...]- the procedure led to conclude that Newtonian Mechanics extracted data from a gedanken experiment. Developing the concept of evolution of states (Entropy), an argument centred on Observability favours a uniform formulation, at the cost of non-linear "Classical" equations.