To, “Is it any good?” I think I have to answer, “Maybe not, but it’s probably as good as we’ll get.” He’s arguing that time is the quantity by which we measure our experience of change. As for whether or not that’s what time fundamentally is, I suspect there’s probably a lot more to it, but whatever it truly is, I’m unable to perceive time without changes taking place in my brain, so it’s a reasonable enough working definition.
To give a slightly silly illustration, imagine the universe as a giant stop motion set and God as the animator who moves everything in it. In between frames, he spends a bazillion real years (whatever those are) moving every fundamental particle into just the place he wants before advancing time as we know it by one Planck unit. Would our perception of time be any different in this scenario than what it is?
Aristotle’s definition really isn’t all that different than that of modern physicists. Units of time have been defined in various ways, but whether it’s a fraction of a day, or a certain number of vibrations of a caesium atom, all involve regular, periodic changes in material things. If anything, the idea of time in modern physics is probably closer to Aristotle’s than it was in Newton’s day.
His definition does look like that of modern physicists, but they certainly wouldn’t refer to our experience of change to argue that time must be defined in terms of change; but then, it is hard to see what other argument can be given for this basic move. Saying for example that we can and do, in fact, define time in terms of the decay of a certain isotope is not to give an argument that should be defined that way.
Thinking more about this after reading your answer, I think you’re correct in suggesting he’s making something of an inductive leap from the fact we can’t experience time without experiencing change to the conclusion that time does not exist without change. I would argue, though, it’s stronger than most such leaps given that it’s necessarily true that we can’t observe the passage of time without change. That’s not true of something like gravity. Even though all our observations of matter are consistent with the idea of gravity, I could still imagine that’s all just been an enormous coincidence and assert that, “There’s no mystical energy field controlling my destiny; it’s all a bunch of simple tricks and nonsense.”
Perhaps I can also imagine time passing without change, but I can’t imagine experiencing time without change. I might be unaware of time passing while anesthetized, but waking up with no wisdom teeth and a mouth full of bloody sponges immediately alerts me to the fact that time has indeed passed. And even if I did somehow observe changeless time, could I recognize it as time? If whiteness were truly fundamental to our concept of swans, it would be as correct to say “all swans are white” as it is to say to say “all swans are birds”. We wouldn’t classify a flying mammal as a swan no matter how much it might superficially resemble one. I might be wrongly imposing Kant’s ideas of phenomenon vs. noumenon onto Aristotle, but I don’t think he’s even attempting to describe time as it fundamentally is, only time as we’re capable of perceiving it.
“Time does not exist without change.” Aristotle seems to support this premise by purely talking about our perception of change and time. Like when we sleep dreamlessly we do not realise time has passed. But the obvious objection is that time has passed, objectively. Only our subjective perception has not realised this until after we wake up. We consult the clock or the person next to us and realise more time has passed than what we had perceived. To me, that says our perception of time can be wrong.
So I don’t get how Aristotle goes from talking about our perceptions to “evidently time is not independent of movement and change.” What he has shown is “our perception of time is not independent of our perception of movement and change.” Those are 2 different things. The jump from the latter statement to the former seems to happen without support. Am I missing something, please show.
I don’t think you’re missing anything, really. Maybe he’s not even making an argument, or maybe he’s arguing for a conceptual connection beteeen time and change based on how we ascertain what time is from our experience of change. See my answer above.
Leave a Reply to Michael Pang Cancel reply