Anatomical Retrofitting: Pi (脾) as Spleen and the Persistence of Ontological Ambivalence

Abstract Over the past decade, medical researchers in China have debated whether the Pi (脾) corresponds to the biomedical spleen or pancreas. This debate exemplifies a broader phenomenon of “anatomical retrofitting”, or the anachronistic imposition of contemporary categories onto living historical objects. “Anatomical retrofitting” as a means of rectifying cases of mistranslation further positions the biomedical spleen and pancreas as representing ahistorical, universal truths. This framework gives rise to a conceptual binary: while the biomedical spleen is universalized as what philosophers may describe as “logical” ontology, the Pi connects to a different nature of reality, or “metaphysical” ontology. Far from being an object of imprecision, the Pi was a dynamic vessel that also shared characteristics with the humoral spleen. Given that scholars in China have already subjected Pi to historical scrutiny, this paper urges scholars to do the same with biomedical anatomy. For instance, historically situating the humoral spleen demonstrates that it became less known and less articulated as it transformed into the biomedical spleen. Meanwhile, the pancreas remained an unstable epistemic object that took on the dynamic functions of the humoral spleen in nineteenth-century organotherapy. Through primary source analysis and literature review, this paper contends that the apparent ontological incommensurability between Pi and spleen is neither mutually exclusive nor irreconcilable. Instead, the dynamic nature of internal viscera, their many functions, and their participation in epistemic practices contribute to an ongoing ontological ambivalence that persists despite the forced certainty of anatomical retrofitting.