The Uncertainty That Matters Isn't Fundamental

I'm on board with a lot of Fundamental Uncertainty. Even some of the stuff that initially feels like a disagreement turns out not to be so. For example, in chapter 8, Gordon writes:Over the course of the previous chapters, I've made the case that truth is fundamentally uncertain. It's not, as many believe, something fixed and eternal, nor is it a matter of pure opinion. Instead, the relative truth we know is grounded, not by absolute truth alone, but by our need for accurate world models to achieve the goals we care about.My first thoughts upon reading this kind of thing are along the lines of "Wtf does it mean for "truth" to be "eternal"? Could you taboo that and give me an example of what you'd use it for?" -- which is exactly turning Gordon's take on truth in on itself, so point taken. Truth is grounded in care, and fundamentally uncertain. I'm with ya here. True enough. It is because of this agreement that I find chapter 8: "Why does fundamental uncertainty matter?" to be the chapter that matters. My answer, however, is quite different: It does not, and it can not. By virtue of talking about the uncertainty which can not be reduced even in principle, we're talking about the part we can't do anything about. The part that there's no reason to care about, because nothing we do can change it. Ah, but it's important to know that we can't change it! Right? Chapter 8 isn't about resolving the unresolvable, it's about knowing what is unresolvable so we don't waste time trying.Except this too, we cannot know.The problem with the "problem of the criterion" is that should we get the criterion wrong, it infects everything. We cannot know that our residual uncertainty is fundamental, because fundamental uncertainty applies here as well. We can't even fall back to "well, sure enough", because to the extent that there's little left, there's little left. To the extent that we have a lot of fundamental uncertainty, we're fundamentally unsure how much and where it is biting us.We