In the map-and-territory distinction, first principles are an example of a map. They are never the territory, they are only used to describe it. So you may observe something play out in reality, according to some principle, but you are not seeing the principle itself.
More precisely, more practically, first principles are the epistemically load-bearing elements of a map:
Now, these principles must possess two conditions: in the first place, they must be so clear and evident that the human mind, when it attentively considers them, cannot doubt their truth; in the second place, the knowledge of other things must be so dependent on them as that though the principles themselves may indeed be known apart from what depends on them, the latter cannot nevertheless be known apart from the former.
Wikipedia article on First Principles (quoting Principles of Philosophy), retrieved March 23, 2026.
The principle that bears a lot of weight may appear strong, solid, but it is still only a principle, part of the map, not the territory. Principles are logical constructs, not physical reality.
The distinction matters, because the model, mistaken for reality, becomes an epistemic dead end.
Merit, as a principle, makes an enticing offer: work hard, make great decisions and you will receive your just rewards. It is an artificial, made-up construct that does not physically exist in the world. There is not anything that you can specifically point to, identifying merit.
When treated and trusted as real, the principle discourages examination. If you work hard and get a positive outcome, then you received your just reward. If you did not get a positive outcome, then according to the merit principle, you did not work hard enough, so did not deserve better. Believing too strongly in the realness of merit, causes a blind spot; you close yourself off to other (perhaps better) ways of explaining an outcome, rendering them entirely invisible.
Relatedly, much like it seems only fair that your hard work should be rewarded with a positive outcome, fairness – as a principle, a quality – is often highly valued. It matters at work, in games and at social situations, where often rules or conventions exist to encourage fair behavior. We fundamentally wish for the world to be a fair place.
Fairness depends entirely on perspective. As such it is fully distinct from physical reality. A rock is a rock, regardless of who is looking. That is simply not the case with your belief about what is fair. So if you mistake the principle for reality, then you are mistaking a perspective for objective truth. But if you do that, not only do you lose sight of this being your perspective, you also risk being blind to other perspectives.
They are often so important to us or fundamental (load-bearing) in our reasoning that it bears reminding. Principles are the map, not the territory.