A Posteriori Theory Adjustment in Contemporary Cosmology

The Cosmic Controversy — the debate over the confirmatory role of the Planck satellite data for inflationary cosmology — raises methodological questions with rich historical and philosophical implications. This paper focuses on one such issue: the disagreement over the legitimacy of a posteriori theory adjustments within the inflationary framework. I argue that inflationary cosmology displays a notable continuity with earlier scientific practice, particularly when examined through the lens of methodological patterns characteristic of early-1970s high-energy physics, such as those seen in the development of electroweak theory. However, I acknowledge a distinctive contextual shift in contemporary cosmology, one that invites a more critical examination of how the same methodological standards are applied today. My historical analysis is framed through the concept of eliminative reasoning, which helps illuminate the shared epistemic roots of the current methodological divide.