 All one can do is describe what has been found to be a very good mathematical model for time and say what predictions it makes.However, the claim that Popper was a positivist is a common misunderstanding that Popper himself termed the "Popper legend".In fact, he developed his beliefs in stark opposition to and as a criticism of positivism and held that scientific theories talk about how the world really is, not, as positivists claim, about phenomena or observations experienced by scientists.