What we can count, or measure

Many like to think mathematics an absolute; Pythagorians actually worshipped it. But in reality it’s no more than a useful kind of mapping, and like any mapping, it simply can’t give accounting for even a significant proportion of all that is, or even of what’s purportedly represented. It’s a tool of some utility, no more.
We experience time, and measure it, first in days, later in other increments. Although we might feel that time has slowed, or sped up, that can only be subjective. One reason is problems of measurement. To test if time changes some kind of rate at high speeds (say, approaching the speed of light), one must determine at what speed the area of testing is moving - and that cannot be done. We have no fixed point, all movement is but in relation to other things - all of which, visibly or not, are also moving. There’re also questions related to changes in measuring apparati, in greatly varied circumstances. If, at great speed, time changes, well, size, and weight, might well change too. It’s quite questionable whether we can establish any meaning from that, especially about the nature of things in general. A small amount of data acquired from a single point of view is as nothing. Even with two points of view, we've hardly enough data to generalize.
So, time remains something we measure but cannot really quantify. How much time do we have? We really don't know. Mass, also, we don't really know about. Inertia we can measure (somewhat), but again we can't get at fundamentals as much as many appear to desire. It’s unlikely that a “god particle” will explain gravity, energy or the fundamentals of existence. One must be outside a system to understand that system.
I wonder if anyone understands money even as well as the best informed among us understand time or mass. I doubt it. It’s similarly a matter of relative proportions, and everything seems to have gotten out of proportion. We tend to fail to take too much into account, usually for ego aggrandizement and self-flattery. We like to think we’ve more going on than we're sure we really do. And it is so, that's true, but often in ways one isn't likely to really like.
What is money? A promise, debt, a contract of obligation - the backing of which by government is of less significance than how much businessfolk will honor it. Our legions of businessfolk, by the way, have become more powerful that our legions of armed forces, and under much less control.