Natural Unity is fundamental unity gained by maintaining strict dependence upon direct empirical evidence and learn from it how to define properties and their units. At the time of the introduction of f=ma, when mass was not defined, it was made the third indefinable property of mechanics. That act caused the immediate loss of fundamental unity from all of physics that has since followed. The only remedy for the return of fundamental unity is for physicists to go back to f=ma and formally define mass. There are just two physics properties that are permanently indefinable. They are length and what physicists call ‘time’. All other physics properties must receive formal physics definitions in the strict historical manner of expressing the property as equal to a combination of other properties that have been previously introduced to us by their direct empirical evidence. This must be done at the time that they are introduced. The units of defined physics properties must be defined in the same manner. All properties are represented in physics equations solely by their units. It is the units that tell us what it is that physicists are really measuring. The return of fundamental unity will return the science of physics to the science of measurements.
James A Putnam