ABSTRACT
The dominant trend in analytic metaphysics is realism about the external world: that there are some things whose identity and persistence is independent of mental activity. If there are natural kinds, then one fact about the fundamental structure of the world is that some things belong together and others do not. If past, present and future entities exist, why are the present entities privileged? What’s so special about present things if it’s not existence? What makes it the case that present entities are metaphysically privileged over the equally existent past and future ones? The idea behind this objection is what motivates what many metaphysicians take to be a useful ontological principle: the truthmaker principle. This principle says that for any truth, there are some things in the world that make that truth true. If the truthmaker principle is true, there is a tight connection between metaphysics, in general, and ontology, in particular.
