Military expansion. The Rashidun Caliphate expanded gradually; within the span of 24 years of conquest, a vast territory was conquered comprising Mesopotamia, the Levant, parts of Anatolia, and most of the Sasanian Empire. Unlike the Sasanian Persians, the Byzantines, after losing Syria, retreated back to Anatolia.
1 And the nature of this reality again can neither be consistently represented as a fixed and hard substance nor as an unalterable something, but only as a fixed order of recurrence of continually changing events or impressions.
noun perÂ·sisÂ·tence \pÉr-Ësis-tÉn(t)s, -Ëzis-\. Tweet. : the quality that allows someone to continue doing something or trying to do something even though it is difficult or opposed by other people. : the state of occurring or existing beyond the usual, expected, or normal time.ull Definition of PERSISTENCE. 1. : the action or fact of persisting. 2. : the quality or state of being persistent; especially: perseverance. See persistence defined for English-language learners. See persistence defined for kids. ADVERTISEMENT.