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27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure

[time is our measure of passing events]

9 ideas
For Aristotle time is not a process but a means for measuring processes [Aristotle, by Bardon]
     Full Idea: For Aristotle time is not a process: It is a kind of 'number' or unit that can be used to describe processes in nature, analagous to the way ordinary numbers can be used to count things.
     From: report of Aristotle (Physics [c.337 BCE]) by Adrian Bardon - Brief History of the Philosophy of Time 1 'Aristotle's'
     A reaction: Bardon cites this when discussing Aristotle on Zeno's paradoxes. If the equivalent idea of length is that length is merely rulers for measuring it, this sounds like a bad idea. But if processes occur in time, how could time be a process?
Time does not exist without change [Aristotle]
     Full Idea: Time does not exist without change.
     From: Aristotle (Physics [c.337 BCE], 218b32)
     A reaction: His reasons are epistemological, and are nicely attacked by Shoemaker, in 'Time without Change'. There is something intuitively wrong about Aristotle's claim. If reality freezes, then 'how long was it frozen?' is a quite reasonable question.
Time is an aspect of change [Aristotle]
     Full Idea: Time is not change, but it is an aspect of change.
     From: Aristotle (Physics [c.337 BCE], 219a09)
     A reaction: I can't think of a better definition of time. Intuition says that time could continue when all change stopped (the 'frozen worlds' thought experiment), so that we can distinguish time from the change that gave rise to it (or the idea of it).
Time is not change, but the number we associate with change [Aristotle]
     Full Idea: Time is a number of change in respect of the before and after. So time is not change but in the way in which change has a number. We discern the greater and the less by number, and greater and less change by time. Hence time is a kind of number.
     From: Aristotle (Physics [c.337 BCE], 219b01)
     A reaction: This is Aristotle's firmest assertion of the nature of time. It seems to be false to say that we need number in order to discern size (e.g. seeing who was given the biggest slice of cake). Surely we discern time before we measure it?
Change only exists in time through its being temporally measure [Aristotle]
     Full Idea: Time measures at once the change and the being of change, and this is what it is, for the change, to be in time, viz. its being's being measured. …This is what it is to be in time: their being's being measured by time.
     From: Aristotle (Physics [c.337 BCE], 221a05)
     A reaction: Among other things, this would presumably mean that animals are unaware of change, which seems unlikely. He may have a relaxed and intuitive (rather than precise) concept of 'measured'.
Time measures rest, as well as change [Aristotle]
     Full Idea: Since time is the measure of change, it will be measure of rest also.
     From: Aristotle (Physics [c.337 BCE], 221b07)
     A reaction: The thought seems to be that change leads us to a system of temporal measurement, which is then available fro measurement periods of rest. But totally eventless time would be a problem. Aristotle had no clocks.
Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]
     Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness.
     From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42
     A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them.
Time is the measure of change, so we can't speak of time before all change [Dummett]
     Full Idea: Time is the measure of change, and it makes no sense to speak of how things were before there was anything that changed.
     From: Michael Dummett (Thought and Reality [1997], 8)
     A reaction: Something creating its own measure sounds like me marking my own exam papers. If an object appears, then inverts five seconds later, how can the inversion create the five seconds? How does that differ from inverting ten seconds later?
Quantum theory relies on a clock outside the system - but where is it located? [New Sci.]
     Full Idea: After general relativity, quantum mechanics reinstated our familiar notion of time. The buzzing of the quantum world plays out according to the authoritative tick of a clock outside the described system, ...but where is this clock doing its ticking?
     From: New Scientist writers (New Scientist articles [2013], 2017.02.04)