A dynamic view is conjectured for not only the universe but also the underlying theories in contrast to the convectional pursuance of a single unification theory. As the 4-d spacetime evolves dimension by dimension via the spontaneous symmetry breaking mechanism, supersymmetric mirror models consistently emerge one by one at different energy scales and scenarios involving different sets of particle species and interactions. Starting from random Planck fluctuations, the time dimension and its arrow are born in the time inflation process as the gravitational strength is weakened under a 1-d model of a ``timeron'' scalar field. The ``timeron'' decay then starts the hot big bang and generates Majorana fermions and $U(1)$ gauge bosons in 2-d spacetime. The next spontaneous symmetry breaking results in two space inflaton fields leading to a double space inflation process and emergence of two decoupled sectors of ordinary and mirror particles. In fully extended 4-d spacetime, the supersymmetric standard model with mirror matter before the electroweak phase transition and the subsequent pseudo-supersymmetric model due to staged quark condensation as previously proposed are justified. A set of principles are postulated under this new framework. In particular, new understanding of the evolving supersymmetry and $Z_2$ or generalized mirror symmetry is presented.