Navigating permanent underdetermination in dark energy and inflationary cosmology

We identify troubling cases of so-called `permanent underdetermination' in both dark energy and inflationary cosmology. We bring to bear (a) a taxonomy of possible responses to underdetermination, and (b) an understanding of both dark energy and inflationary cosmology from an effective field theory point of view. We argue that, under certain conditions, there are viable responses which can arguably alleviate at least some of the concerns about underdetermination in the dark energy and inflationary sectors. However, the epistemic threat of permanent underdetermination remains a significant challenge.