Definitions can not be correct or incorrect, it's a decision, you can define something however you want in principle. — ChatteringMonkey

Again: they're not my definitions.

They can be more or less useful though, and I'm saying they don't seem to be very useful if they only apply to a theory of time that can't be the case and that nobody believes in. — ChatteringMonkey

You seem to imply that nobody believes in the B-theory of time, that time does not flow. Do you have any support for this claim?

I'm done with the thread, I said what I have to say.

But a lot of scientists believe in eternalism, and I'm pretty sure very few of them believe that there can be no motion under it. Are they just all that stupid for not realizing that motion is impossible under eternalism, or doesn't it have to entail that and the presupposed qualification sceme is simply misguided? — ChatteringMonkey

There's another option, that they believe there's something outside the eternalism framework, which provides the special metaphysical status for something like a spotlight theory. That these people are scientists, and this principle lies outside the discipline of science is reason why they would believe in it without giving it much thought. One can believe in eternalism, and also believe that eternalism gives an incomplete representation of time, without speculating about what is required to complete it. The discipline of science does not require that one speculate about the principles being applied.

I don't think anybody claims that these theories of time are complete physical theories. The way I see it that they are merely theories about time that could possibly fit our experiences. And my point is that I don't see that there is anything in eternalism per se that precludes motion, unless you define it as such.

The best way to know the meaning of something is to consider different scenarios and whether you would call it that. An example is the meaning of knowledge. Would you Call a guess Knowledge? If the teacher asks you a question, then you give some random number then it turns out to be right, then is that knowledge. No, so its something that is gained through justified process. This is an example of using this method and you would continue with different situations until you reach a meaning that satisfies the purpose at the moment.

With Time, the first thing you got to ask is, is Today time? No, rather you would say that "I have a class at that time". From this we can say time may be an ordered set collection of something. We only talk about time in relation to events. From this I know an event is the entire description of all reality. The present can be called the Description of reality that is true, while past events are the events that was once the present but is no longer true. The present is the reference point of the past events in which was true and not true.

A visual would be

E3, E2, E1, Present

E3 essentially means that it was the present

E3, E2, E1, Present(E3 from previous)

E3, E2, E1(E3), Present

E3, E2(E3), E1, Present

Then the present became different thus a new present and and the present that was is now a past event. All of this takes the present as the reference point since the description of reality is what exists. Past event exists only as true statements. You guys should not be confuse Time with the measurement of change of phenomenon, like I climbed the mountain in three days. The event of the first day is you were at the the initial and the third day you are at the top. It is just individual occurrences which are related to one another.

The future is actually can only be a called when the present becomes the past thus the present now can be called an event after a past event. Which means the future the relation of past events to the present.

I don't see that there is anything in eternalism per se that precludes motion, unless you define it as such. — ChatteringMonkey

And in which case, mightn't this be turned around:

... objects are arranged in space in an orderly way. Their arrangement can be described without referring to "passage of space" or some equivalent of motion. — Echarmion

...?

Spatial patterns just as well can be described in terms of change and motion and passage. The rectangle changes (moves, passes, travels) from red to yellow, from left to right; and a rate of change is measured with respect to a horizontal position, which may represent time or (just as easily) any variable you like (hence we say the rectangle is coloured with a "gradient").

I don't think anybody claims that these theories of time are complete physical theories. The way I see it that they are merely theories about time that could possibly fit our experiences. And my point is that I don't see that there is anything in eternalism per se that precludes motion, unless you define it as such. — ChatteringMonkey

Nothing in eternalism "precludes" motion but the theory does not provide any principles which would allow for the actual existence of motion. So if one adheres to eternalism without any amendments, as a representation of the universe, this would be a universe without motion.

Nothing in eternalism "precludes" motion — Metaphysician Undercover

Unless you are talking about the Moving Spotlight theory (which I consider to be a hybrid of Eternalism and Presentism/A-theory, rather than true Eternalism), or unless you can provide an explanation for how motion is possible under B-theory Eternalism (i.e. without temporal passage), then I think it is clear that Eternalism does logically preclude motion.

As evidenced in this thread, there are Eternalists who will complain, with some saying that nobody really believes in this form of Eternalism. However, these same folk reject Presentism, while simultaneously wanting to retain the temporal passage and motion that belongs to Presentism. Do these folk allow the same concessions to Presentists when pointing out the shortcomings of Presentism? Perhaps. Maybe @ChatteringMonkey is right that nobody really believes in this extreme, pure version of Eternalism, and the same probably applies at the other end of the spectrum, too, but I think it's worth pointing out what those extremes entail. Criticisms of Presentism just seem to be much more prevalent.

Criticisms of Presentism just seem to be much more prevalent. — Luke

I think that's because the criticism is of a different order, not merely definitional. A universal now or present has been shown to be a problematic idea in relativity. So either you say relativity is wrong, which will be a hard sell because it has been tested over and over again, or you adjust presentism and maybe you could save some sort of universal now or present that accounts for relativity. Or you bite the bullet of relativity entirely and adjust the theory so that it only allows for local nows, which gets you close to some kind a solipsism.

I think that's because the criticism is of a different order, not merely definitional. A universal now or present has been shown to be a problematic idea in relativity. So either you say relativity is wrong, which will be a hard sell because it has been tested over and over again, or you adjust presentism and maybe you could save some sort of universal now or present that accounts for relativity. Or you bite the bullet of relativity entirely and adjust the theory so that it only allows for local nows, which gets you close to some kind a solipsism. — ChatteringMonkey

Yes, I wasn't asking for a repeat of the criticism. Do you acknowledge that Eternalism logically precludes motion, or do you have any further defence to offer?

No, on that point I'm only going to repeat myself.

Unless you are talking about the Moving Spotlight theory (which I consider to be a hybrid of Eternalism and Presentism/A-theory, rather than true Eternalism), or unless you can provide an explanation for how motion is possible under B-theory Eternalism (i.e. without temporal passage), then I think it is clear that Eternalism does logically preclude motion. — Luke

The point was that eternalism does not make motion impossible, because all you have to do is add more premises, like your spotlight theory does. Therefore we cannot say that it precludes motion.

Maybe ChatteringMonkey is right that nobody really believes in this extreme, pure version of Eternalism, and the same probably applies at the other end of the spectrum, too, but I think it's worth pointing out what those extremes entail. Criticisms of Presentism just seem to be much more prevalent. — Luke

Criticism of presentism is easy, because it is the simple position, and one simply needs to refer directly to special relativity to criticize it. Criticism of eternalism is more difficult because it requires understanding eternalism, which is a more complex position.

The point was that eternalism does not make motion impossible, because all you have to do is add more premises, like your spotlight theory does. Therefore we cannot say that it precludes motion. — Metaphysician Undercover

Do you agree that the Moving Spotlight theory is a hybrid of Eternalism and Presentism/A-theory? If so, then it's not Eternalism.

I don't see how that's relevant.

You said that Eternalism doesn't preclude motion "because all you have to do is add more premises, like your spotlight theory does". The Moving Spotlight theory (which is not mine) is a hybrid of Eternalism and Presentism; it is as much a form of Eternalism as it is a form of Presentism. I'm not sure what "premises" you are referring to. Regardless, I don't think that any of the Eternalists here are willing to accept the Moving Spotlight theory as their form of Eternalism. I'm happy to refer to it as B-theory Eternalism or the block universe theory, as I did in the OP, to avoid any ambiguity. Like most Eternalists, I'm quite sure this is what the Eternalists in this discussion are arguing for anyway.

what is motion but a spatial path in spacetime anyway? — jorndoe

To reiterate my argument against this general assumption by the Eternalists: Assume a four-dimensional object exists at every point between t1 and t2. What moves? Even if the start of the 4D object is at position x1 at t1 and the end of the 4D object is at position x2 at t2, it still would not have moved from x1 to x2, because this would be to treat the four-dimensional object as a three-dimensional object ("modulated by the passage of time") instead.

Even if the start of the 4D object is at position x1 at t1 and the end of the 4D object is at position x2 at t2, it still would not have moved from x1 to x2, because this would be to treat the four-dimensional object as a three-dimensional object ("modulated by the passage of time") instead. — Luke

Yes and this is the core of our disagreement since the beginning, I just don't see why you need something like "passage of time" to say that something moves. Because what is motion other that something changing position over time, that is literally the definition of motion.

What is the argument here? Maybe you don't agree with that definition of motion? Or you think, because the object exist over time, that no movement can happen because there are no separate existences? Or you think that because a lack of direction, or preferred moment, something cannot be said to move because that requires a (preferred) reference point? Or... ?

Because what is motion other that something changing position over time, that is literally the definition of motion. — ChatteringMonkey

What "something" are you are talking about here? Is it a 3D object which starts at t1 and moves to t2? Or is it a 4D object which exists at t1, t2, and all points in between? You seem to assume that existence at all points is the same as moving from one point to another.

You seem to assume that existence at all points is the same as moving from one point to another. — Luke

It is the same, because they don't exist at all points at the same time.

What "they"? Is it a 3D object or a 4D object? You don't get to assume it's a 3D object as an Eternalist, so how can it move through time? What moves?

Ok, I think I understand how you view it now.

An 'object' is not something that is set in metaphysical stone. A table is an object, but you can just as well describe it by its parts, or by the atoms it is made out of... it's a convention, or a decision where we draw the lines of an object. And so yes why not split a 4d object up into 3d objects...

So what moves? Whatever part of the 4d object that changes position over time.

Why would you think that lines that are arbitrarily drawn by us humans, that the language we choose to use, would have consequences for the nature of reality?

And yes why not split a 4d object up into 3d objects... — ChatteringMonkey

Because then you'd be talking about Presentism and/or the A-theory instead of B-theory Eternalism.

Why would you think that lines that are arbitrarily drawn by us humans, that the language we choose to use, would have consequences for the nature of reality? — ChatteringMonkey

I'm not really concerned with it. I'm interested in the logical implications of the concepts.

I'm not really concerned with it. I'm interested in the logical implications of the concepts. — Luke

Ok then, are you a rationalist maybe?

In eternalism, what word would you use to differentiate between a 4d object that only exists at one place and a 4d object that exists over multiple positions?

So what moves? Whatever part of the 4d object that changes position over time. — ChatteringMonkey

So 3D parts of the 4D object change position over time, despite the fact that the 4D object as a whole does not change position over time. Isn't this just smuggling in Presentism and/or the A-theory?

In eternalism, what word would you use to differentiate between a 4d object that only exist at one place and 4d object that exists over multiple positions? — ChatteringMonkey

In eternalism, I see no need to differentiate between them. To what end?

In eternalism, I see no need to differentiate between them. To what end? — Luke

To our ends of course, as human beings. Even if eternalism is true, we would only experience part of it, and things existing over multiple positions over time presumably would be still of interest to us.

So 3D parts of the 4D object change position over time, despite the fact that the 4d object as a whole does not change position over time. Isn't this just smuggling in Presentism and/or the A-theory? — Luke

No I don't thinks so, you need another concept of movement, like I said earlier.

To our ends of course, as human beings. Even if eternalism is true, we would only experience part of it, and things existing over multiple positions over time presumably would be still of interest to us. — ChatteringMonkey

It seems like you want me to say that one moves and one doesn't, or that one contains motion and one doesn't, except, in eternalism, neither moves and neither contains motion.

Put simply, 3D objects move; 4D objects don't.

So 3D parts of the 4D object change position over time, despite the fact that the 4d object as a whole does not change position over time. Isn't this just smuggling in Presentism and/or the A-theory?
— Luke

No I don't thinks so, you need another concept of movement, like I said earlier. — ChatteringMonkey

You "need another concept of movement" for what?