31. Rational Choice Utility function Peer group Scientists Akin to Natural selection Epistemic symmetry No Empirical Social phenomena Hard core& Outer Theoretical Core Both T/F Paradigm& Paradigm Shift incommensurability Context of Justification Context of Discovery incommensurable Social External factors Sophisticated falsification Verisimilitude Falsificationism David bloor,Barry Barnes Imre Lakatos Thomas Khun Karl Popper