 Several other philosophers and physicists have come forward with similar ideas. Aharonov and Vaidman (1997) have formulated a two vector approach to quantum mechanics “in which a quantum system is described, at a given time, by two (instead of one) quantum states: the usual one evolving toward the future and the second evolving backwards in time from a future measurement.” Also Cramer’s transactional interpretation of quantum mechanics involves the idea of a second wave travelling backwards in time (Cramer, 1986). The basic assumption behind all of them is that in the micro-world we find only causal symmetry, and this fact together with proper boundary conditions can be used to give an explanation of outcomes that seem otherwise paradoxical. Such quantum correlation experiments can, however, be interpreted in many other ways. In the end it seems as if it all depends one whether one assumes that Bell experiments break with either the locality condition or the separability condition. A time-symmetric interpretation of quantum mechanics is required only if one believes that it is the locality condition that is violated in order to avoid being in conflict with relativity theory.