This chapter discusses the debate between the existence of the past versus presentism in the academic debate. A first conclusion is that there seems to be a stalemate that cannot be decided by purely theoretical philosophical arguments. In an attempt to break this stalemate, philosophical interpretations of physics are taken into account. Yet, it is shown that here, too, there are good arguments both for and against the existence of the past—as the theory of relativity seems to suggest that all times exist equally, but the fact that the dynamics of physics only ever require the state of the world at the current time to predict the future, combined with Ockham’s razor, suggests that only the present exists.