Naturalness in the Making: Classifying, Operationalizing, and Naturalizing Naturalness in Plant Morphology

What role does the concept of naturalness play in the development of scientific knowledge and understanding? Whether naturalness is taken to be an ontological dimension of the world or a cognitive dimension of our human perspective within it, assumptions of naturalness seem to frame both concepts and practices that inform the partitioning of parts and the kinding of kinds. Within the natural sciences, knowledge of what something is as well as how it is studied rely on conceptual commitments. These conceptual commitments shape how entities and processes are categorized as natural depending on how naturalness has been understood within that discipline. In this paper, I explore how commitments to naturalness shape different conceptualizations of what were previously and what are now considered to be fundamental parts in plant morphology. Relying on an historically informed epistemological approach, I trace the origins and development of models of plant morphology from (1) Goethe’s classical LEAF-ROOT-STEM archetype model; (2) Agnes Arber’s revisions to Goethe’s model reconceived in her partial-shoot theory of the leaf; and (3) Rolf Sattler’s proposal for a processual model of plant morphology. These influential models posit ontologically and epistemologically inconsistent conceptualizations of the natural fundamental parts of plants and how they are related to each other. To explain what this inconsistency means for the concept of naturalness and the role it plays in plant morphology, I suggest naturalness might best be conceived of as a contextually bound classificatory concept that is made and remade through its operationalized use within a model, theory, set of practices, or discipline.