Giuseppe Primiero (joint work with Franco Raimondi) Software Theory Change for resilient near-complete specifications Abstract We model early-stage perfective and corrective changes to software system architecture in terms of logical operations of expansion and safe contraction on a theory. As a result, we formulate an inference-based notion of property specification resilience for computational systems, intended as resistance to change. The individuated resilient core of a software system is used to characterize adaptability properties.