  In this paper I argue that the fundamental aspect of our notion of time is
that it defines an order relation, be it a total order relation between
configurations of the world or just a partial order relation between events.
This position is in contrast with a relationalist view popular in the quantum
gravity literature, according to which it is just correlations between physical
quantities that we observe and which capture every aspect of temporality in the
world, at least according to general relativity. I argue that the view of time
as defining an order relation is perfectly compatible with the way general
relativity is applied, while the relationalist view has to face some
challenges. This debate is important not only from the perspective of the
metaphysics of space and time and of how to interpret our physical theories,
but also for the development and understanding of theories of quantum gravity.
