Does Explaining Past Success Require (Enough) Retention? The Case of Ptolemaic Astronomy

Abstract According to selective, retentive, scientific realism, past empirical success may be explained only by the parts of theories that are responsible their successful predictions being approximately true, and thus theoretically retained, or approximated, posterior same predictions. In this article, we present as case study transit from Ptolemy’s Kepler’s astronomy, for Mars’ orbit. We an account prediction orbit perspective, scrutinize whether theoretical elements retained in Kepler. order give realist best chances, try different strategies. conclude all fail thereby constitutes a prima facie strong anomaly selective retentive realism. Structural realists call preservation structure rescue, but existing notions do not work. absence new notion works, burden proof lies on side.