Physical reality in planetary geomorphological inference and the pathway to a critical planetary geology

Abstract

I engage the philosophy of geology, and the philosophy of planetary geomorphology in particular, offering a perspective from the standpoint of a Mars geographer who is acquainted with both experimental and social research. I discuss the nature of geological reasoning and probe its somewhat paradoxical commitment to both a physical realism and to interpretative narrative construction, engaging particularly with how the interplay of these two factors are addressed in the works of the philosopher-geologist Victor Baker. I also draw attention to specific characteristics of knowledge construction in Martian geomorphology which systemically limit the attachment of our inferences to a physical reality. For instance I highlight a geospatial-geochemical dimorphism in the semantic content of available planetary data and several non-scientific controls on the knowledge construction process, including mission safety constraints and sociopolitical factors.Lastly, I find that physical geography has grown apart from planetary geomorphology in the decades since planetary geomorphology assumed its largely geological modern form. An academic siloing effect has followed suit. An immediate implication is that this contours the typical pathways of knowledge construction in our discipline, and I try to call attention to a few examples of this effect. As an effort to bridge this gap, I highlight the recent developments of the physical geographical subdisciplines of GIScience and critical physical geography. These disciplines offer opportunities for insight which might be fruitful for planetary geomorphologists, but their lines of inquiry have largely passed beneath our community’s radar. Specifically, in offering examples of what discourse in a critical planetary geology might look like, I hope to encourage the informal philosophical discussions already circulating in our community to pass into a formal space of debate.