How Is the Asymmetry Between the Open Future and the Fixed Past to Be Characterized?

Abstract

A basic intuition we have regarding the nature of time is that the future is open whereas the past is fixed. However, although this intuition is largely shared, it is not a straightforward matter to determine the nature of the asymmetry it reflects. So, in this chapter, I survey the various philosophical ways of characterizing the asymmetry in openness between the future and the past in order to account for our intuition. In particular, I wonder whether the asymmetry is to be characterized in semantic, epistemic, anthropocentric, physical, modal, metaphysical or ontological terms. I conclude that an ontological characterization of the asymmetry is to be preferred, since it is superior to the alternatives in explanatory power, intelligibility, and in how it coheres with interesting senses of openness.