Philosophy Now Forum

bahman wrote:But the particle exists in both positions, X and Y. So there is not really any motion of particle when our perspective changes. Hence the motion is an illusion in block universe.

"Think of a point particle for simplicity." <--I was quoting you there just in case that wasn't clear to you.

--Here we're talking about our perspective rather than just a point particle obviously-- <--I'm explaining how your definition of motion fits talking about our perspective instead.

--Our perspective exists in position X and does not exist in position Y at the initial time--

Terrapin Station wrote:

bahman wrote: But the particle exists in both positions, X and Y. So there is not really any motion of particle when our perspective changes. Hence the motion is an illusion in block universe.

C'mon man--I just spelled all of that out for you. I'm not talking about a particle. I'm talking about our perspective above:

For example:

"Think of a point particle for simplicity." <--I was quoting you there just in case that wasn't clear to you.

--Here we're talking about our perspective rather than just a point particle obviously-- <--I'm explaining how your definition of motion fits talking about our perspective instead.

And re our perspective:

--Our perspective exists in position X and does not exist in position Y at the initial time--

So OUR PERSPECTIVE HAS MOTION PER YOUR DEFINITION OF MOTION. Not a particle. Our perspective.

Thus there is motion in this picture of the universe. Namely, our perspective is in motion.

We cannot say there is no motion in this universe. There IS motion--our perspective is in motion, per the definition of motion you gave.

"Motion to me is the change in state of matter"

(1) --In this case the change in state of our perspective--

"from an initial time to a latter time."

(2) --So a change in state of our perspective from an initial time to a later time--

"Think of a point particle for simplicity."

(3) --Here we're talking about our perspective rather than just a point particle obviously--

"The particle exists in position X and does not exist in position Y, at initial time"

(4) --Our perspective exists in position X and does not exist in position Y at the initial time--

"and latter time. The particle does not exist in initial time, position X, and exists only at final time, position Y. "

(5) --At the later time (or the latter time), our perspective does not exist in the initial time at position X, but only at the final time at position Y--

"This is what we call motion in my opinion."

(6) --Yes. So then you should call this change or movement in our perception "motion," and thus the proposed block universe has motion after all; it's not motion-free.

bahman wrote:I don't understand why you stress that our perspectives are in motion.

Terrapin Station wrote:

bahman wrote: I don't understand why you stress that our perspectives are in motion.

Because the idea of a motionless universe is incoherent nonsense. I'm trying to help you see this.

Terrapin Station wrote: "Motion to me is the change in state of matter"

(1) --In this case the change in state of our perspective--

Terrapin Station wrote: "from an initial time to a latter time."

(2) --So a change in state of our perspective from an initial time to a later time--

Terrapin Station wrote: "Think of a point particle for simplicity."

(3) --Here we're talking about our perspective rather than just a point particle obviously--

Terrapin Station wrote: "The particle exists in position X and does not exist in position Y, at initial time"

(4) --Our perspective exists in position X and does not exist in position Y at the initial time--

Terrapin Station wrote: "and latter time. The particle does not exist in initial time, position X, and exists only at final time, position Y. "

(5) --At the later time (or the latter time), our perspective does not exist in the initial time at position X, but only at the final time at position Y--

Terrapin Station wrote: "This is what we call motion in my opinion."

(6) --Yes. So then you should call this change or movement in our perception "motion," and thus the proposed block universe has motion after all; it's not motion-free.

Terrapin Station wrote: Okay, so re statement (4), which is where the first significant disagreement is occuring (because (1) is about a block universe, (2) you agreed with, and (3) is just establishing what we're talking about--perspective in this case rather than a particle), you disagree with this:

"Our perspective exists in position X and does not exist in position Y at the initial time"

(although note AGAIN that what you're supposed to be addressing there is OUR PERSPECTIVE, not "a particle")

But at any rate you apparently disagree with "Our perspective exists in position X and does not exist in position Y at the initial time"

So you'd say that in a block universe, our perspective exists both in position x and y at the same time?

bahman wrote:No, our perspective exist in x first and then y later.

Terrapin Station wrote: [quote="bahman"
No, our perspective exist in x first and then y later.

bahman wrote:I hesitate to use the word motion for changing perspective since we define motion for another thing. That is it.

bahman wrote:We have a change in perspective, movement along time axis, which causes a change in position of things. This is however different from what I call motion.

Terrapin Station wrote:

bahman wrote: I hesitate to use the word motion for changing perspective since we define motion for another thing. That is it.

So "motion" doesn't hinge on "just any old thing" fitting into the definition. It only pertains to particular sorts of things?

Noax wrote:

bahman wrote: We have a change in perspective, movement along time axis, which causes a change in position of things. This is however different from what I call motion.

I think this post sums up the inconsistency.

In a block universe, there is you at Aug 24 and you at Aug 25, and you're incorrectly stating that the perspective changes. Is there no a bahman at Aug 24? Does that bahman in fact have the Aug 24 perspective? What exactly changed/moved? A block universe model states that you exist at all times, and nothing (perspective) travels from one point to another. OK, epiphenomenal dualistic mind might be able to travel through that, and you seem to assume this stance but then find conflict with it. But any other view does not have a 'current' perspective in a block model.

Yes, there is change and motion in the block universe. It is not an illusion. Thing X is in different states at different times, and that's motion/change, not the illusion of it.