Volume
Basis: 1 dec = 1 cubic dis (approx 0.026944002 Earth cm3)
Agreed to almost immediately.
Mass
Basis 1: 1 pos = mass of 1 proton (approx. 1.6726231 × 10-30 Earth grams)
Basis 2: 1 pin = the mass of pure water in 1 dec (approx. 26.94327493 Earth milligrams)
The proton was chosen as it is stable, universal, and the smallest commonly measured quantity among the civilization participating in the Convention. This choice was easily accepted. The topic of much debate was the scaling ratio for a reasonably useful “real world” basis. While the desire to maintain symmetry with the base-10 system was greatly desired, the formulas designed to achieve a “useful” basis were deemed too contrived. Bowing to simplicity, a physical measurement was used instead — as water was available in quantity on every world with a sentient civilization, it’s pure form at maximum natural density was to be used as the standard element of choice.
