Certain aspects of magical force certainly are, like Initiate Grade, or Foci Forces, because grades are clearly deliniated things and are referenced I believe in the Jackpointer profiles, and Foci forces are specifically chosen.
Spells used to also have objective grades, as spell formulae had to be learned at specific grades.
Other stuff is less clear. In theory, the universe has enough tools to measure force objectively (Ex: Assensing telling you if you are weaker or stronger than something lets you create an objective scale that would become accurate if a group of mages recorded their assessments of each other's power levels). Likewise, this would let you determine force to some extent if you desired (have the mages, once their power levels are quantified, summon the strongest spirits they can, and compare them).
However, this is a bit like quantifying strength scores by having characters all test each other's carry weight. Its a BIT more natural with magic, but it would still be weird. It might be appropriate to measure magic on SOME scale that isn't the 1-6+ scale (Like a magic 3 mage could score anywhere from 2799-3800 'manawatts' or whatever from their aura), or it could remain a nebulous comparison thing. I would lean to the second, or at least have the first be VERY innacurate and fuzzy and not easy to measure at all, as part of the nature of RPGs is to codify things to specific absolute values, but in general capacities of people don't work like that, its an abstraction, and avoiding characters talking about any sort of 'magic score' helps avoid everyone feeling like they are in a videogame.
