Abstract

Ever since the heyday of the Vienna Circle, scientific realists have worked hard to document and clarify the structure and growth of truth content in theoretical descriptions. Today, this trait is particularly intense among “selective realists” – realists focused on theory parts with high empirical corroboration rather than whole theories. From their perspective, theories with posits systematically deployed in corroborated novel predictions are, with high probability, descriptively true or contain a proper part that is. Unlike traditional realists, selectivists acknowledge that (a) radical conceptual change is a recurring scientific phenomenon and (b) empirical theories have poor reliability records at the most profound ontological level. At the same time, they point to significant descriptive continuities at intermediate theoretical levels between successful theories and their successors – i.e., a false theory can (and often does) contain parts that succeed as correct descriptions. Selectivists seek to identify those parts. Their approaches limit ontological commitment exclusively to highly confirmed theoretical descriptions; unfortunately, the selection criteria they use seemingly support many regrettable choices. One source of trouble is that extant approaches leave unclear the ontology described by the selected parts. Historical cases and scientific practice gesture toward a functional resolution of this difficulty, but the clues could be more transparent and need elaboration. Otherwise, selectivism has improved in consistency over the last three decades. Current projects emphasize the continuity of well-established scientific content (relating to how entities and processes effectively behave within a specific regime or descriptive level) instead of just the continuity of “structure”. This paper provides some clarifications that arguably clear the road for realist commitment toward functional and effective theoretical content. The proposed functional/effective turn is checked against some plausible objections.