Summary

Abstract

What is time? ‘Time is the measure of motion.’ True, maybe, but hardly illuminating as to the inner nature of time – hardly a definition or analysis of time. Motion, after all, is change of location over time. ‘Time is the possibility of change.’ That too may be true. But it’s also circular: the possibility of change is the possibility for a single thing to have different properties at different times. ‘Time is the order of events.’ Order in terms of what? Size? Importance? No: order in time.1 A definition of time would have to define it in atemporal terms. But what terms might those be? What transcends time? Logic. Mathematics. But if we can define time in purely logical or mathematical terms, then time must be a purely logical or mathematical entity. Like a set or a number, time would be an abstraction, its nature knowable a priori, if at all. But time is not like a number, and its nature cannot be known without empirical investigation. So we can’t define time in purely logical or mathematical terms. So we can’t define it at all. Time is conceptually and metaphysically primitive. It has no inner nature. It is part of the ontological bedrock.