Need expert advice on how to handle a seemingly legitimate objection

[fast]

I do.

Speaking of imaginary points, just curious, how fast are we moving? If you say relative to what, let's make it relative to imaginary points one earth hour away from each other. For example, at 11:30 est, stick your hand in the air and point. The area of the universe that the tip of your finger takes up will be imaginary point 1. Exactly one hour later, as indicated by the time on your cell phone, stick your hand in the air and point again. Let that area of the universe right where the tip of your finger is be imaginary point 2. If we were to measure the fixed distance between the two points, how many miles would it be?

1. Relative to the tip of my finger, the point at the tip of my finger doesn't move at all.

2. I want to say anywhere from about a thousand miles (at the equator) to zero (at the pole) but I'm having trouble nailing down what that is relative to. Perhaps it's relative to the center of the earth?

3. We could get different figures by treating the sun as stopped, or the center of the galaxy.

4. For that matter, we could take the frame of reference of your belt buckle, a migrating owl, or a curing cheese---anything at all except a photon. (And I'm not sure about the photon.)

Each of these answers is as true as the others, because all motion is relative to the observer.

it did come to me that the distance travelled is greater than the distance from the two points because of the planets rotation. To illustrate, imagine using a magic marker and putting a dot on the side of a frisbee. Throw the frisbee in a strait line to someone else. The distance between the two people is one thing, but capture the path of that dot on a high speed recorder and map the path the dot takes as it swirled around and around--to see that it doesn't go in a straight line. Your finger is that dot, but the point in space is where the frisbee first left your hand. So, the poles of the planet won't play apart in calculating the distance between the two points--that would only perhaps be important if measuring the distance travelled of your finger.

 

[Wiploc]

it did come to me that the distance travelled is greater than the distance from the two points because of the planets rotation. To illustrate, imagine using a magic marker and putting a dot on the side of a frisbee. Throw the frisbee in a strait line to someone else. The distance between the two people is one thing, but capture the path of that dot on a high speed recorder and map the path the dot takes as it swirled around and around--to see that it doesn't go in a straight line. Your finger is that dot, but the point in space is where the frisbee first left your hand. So, the poles of the planet won't play apart in calculating the distance between the two points--that would only perhaps be important if measuring the distance travelled of your finger.

I didn't follow all of that, but I'm willing to say that there may be a point of view from which that all seems true. There are, of course, other points of view (frames of reference) that are just as valid.

 

[fast]

it did come to me that the distance travelled is greater than the distance from the two points because of the planets rotation. To illustrate, imagine using a magic marker and putting a dot on the side of a frisbee. Throw the frisbee in a strait line to someone else. The distance between the two people is one thing, but capture the path of that dot on a high speed recorder and map the path the dot takes as it swirled around and around--to see that it doesn't go in a straight line. Your finger is that dot, but the point in space is where the frisbee first left your hand. So, the poles of the planet won't play apart in calculating the distance between the two points--that would only perhaps be important if measuring the distance travelled of your finger.

I didn't follow all of that, but I'm willing to say that there may be a point of view from which that all seems true. There are, of course, other points of view (frames of reference) that are just as valid.

http://starryskies.com/articles/2007/11/earth-speed.html

Just a little something

 

[steve_bnk]

The sentence "Quadruplicity drinks procrastination" was coined by Bertrand Russell as a typical meaningless sentence to make the point that such sentences are neither true nor false.

But W.V. Quine disagreed with him. According to him, for a sentence to be false is nothing else but for it not to be true. Quadruplicity doesn't drink anything, so the sentence is just false.
EB

I think I agree with Russell. Phrases like that fall under the category of "Not even wrong". Something being false implies that you can look at the statement and point to where it is that it fails a truth test. Meaningless phrase are just ... meaningless.

[...] History has plenty of examples of terms and expressions that would have been meaningless to people a century ago, or even ten years ago, which now have definitions in dictionaries. That we don't understand it also doesn't entail that the person saying it doesn't mean anything.

The meaning of a term is independent of what a person may happen to mean when using a term.

Fast says...

'...Let me start over. If I'm correct and inductive arguments (a kind of non-deductive argument) are not the kinds of arguments that are invalid (or valid, for that matter) yet true to say of them that they are not valid arguments (and of course not invalid either), and if you agree with me (or if you can expound on the issue despite a contrary belief), what are some possible counter arguments to the objection that the very meaning of the word, "invalid" is not valid...'

Lord have mercy, the mother of all ironies.

 

[fast]

The sentence "Quadruplicity drinks procrastination" was coined by Bertrand Russell as a typical meaningless sentence to make the point that such sentences are neither true nor false.

But W.V. Quine disagreed with him. According to him, for a sentence to be false is nothing else but for it not to be true. Quadruplicity doesn't drink anything, so the sentence is just false.
EB

I think I agree with Russell. Phrases like that fall under the category of "Not even wrong". Something being false implies that you can look at the statement and point to where it is that it fails a truth test. Meaningless phrase are just ... meaningless.

[...] History has plenty of examples of terms and expressions that would have been meaningless to people a century ago, or even ten years ago, which now have definitions in dictionaries. That we don't understand it also doesn't entail that the person saying it doesn't mean anything.

The meaning of a term is independent of what a person may happen to mean when using a term.

Fast says...

'...Let me start over. If I'm correct and inductive arguments (a kind of non-deductive argument) are not the kinds of arguments that are invalid (or valid, for that matter) yet true to say of them that they are not valid arguments (and of course not invalid either), and if you agree with me (or if you can expound on the issue despite a contrary belief), what are some possible counter arguments to the objection that the very meaning of the word, "invalid" is not valid...'

Lord have mercy, the mother of all ironies.

that's what I'm here for ...

 

[Wiploc]

it did come to me that the distance travelled is greater than the distance from the two points because of the planets rotation. To illustrate, imagine using a magic marker and putting a dot on the side of a frisbee. Throw the frisbee in a strait line to someone else. The distance between the two people is one thing, but capture the path of that dot on a high speed recorder and map the path the dot takes as it swirled around and around--to see that it doesn't go in a straight line. Your finger is that dot, but the point in space is where the frisbee first left your hand. So, the poles of the planet won't play apart in calculating the distance between the two points--that would only perhaps be important if measuring the distance travelled of your finger.

I didn't follow all of that, but I'm willing to say that there may be a point of view from which that all seems true. There are, of course, other points of view (frames of reference) that are just as valid.

http://starryskies.com/articles/2007/11/earth-speed.html

Just a little something

We get conventional ways of talking that can be useful shorthand without being precise. We might say, for instance, that giraffes grew their long necks so they can reach high leaves. Someone who believes the earth really goes around the sun may speak of the sun "rising."

Your starry skies article conveys interesting information, expressed somewhat sloppily. They would probably express themselves differently if they were discussing the topic you and I are discussing.

Some parts of the article, I suspect, are just plain wrong, not a matter of loose terminology. Consider this bit:

[QUOTE = http://starryskies.com/articles/2007/11/earth-speed.html]To talk about where we are going, we must have a reference point, and for that we will choose the beginnings of the universe – the Cosmic Background Radiation (CBR) left over from the fires of creation. We are moving away from that, as are all things in the universe. But which direction? Go out on a spring night and find the constellation Leo the lion. The Earth is moving towards Leo at a speed of 390 kilometers per second.[/QUOTE= http://starryskies.com/articles/2007...rth-speed.html]

The CBR comes from all points of the compass. There is not even a sloppy sense in which we can be moving away from that.

 

[fast]

It's quite apparent now that the speed that we say something is moving is a speed that is relative to something else...thank you. However, that there are no (oh say) mile markers giving us a true speed that need not be relative to other objects (even if such speeds can be measured relative to other objects), that doesn't necessarily entail there is no actual true speed we're moving. I say this under the notion that our inability to measure it doesn't necessarily entail there is no it. I'm not convinced there is no true speed.

 

[Speakpigeon]

I feel that failures of communication do not indicate failure or successes of logic. While failures of communication is a subject worthy of a lot of study it doesn't necessarily belong in a thread on logic.

I think it's here in Logic because it's about the notion of validity/invalidity.
So it's about the semantic of logic...
EB

 

[fast]

What is an example of a valid non-deductive argument?

 

[zorq]

What is an example of a valid non-deductive argument?

1 Almost all dogs are less than 1000 kg
2 Rex is a dog.
3 Rex is probably less than 1000 kg

 

[fast]

What is an example of a valid non-deductive argument?

1 Almost all dogs are less than 1000 kg
2 Rex is a dog.
3 Rex is probably less than 1000 kg

If 1 and 2 are true, then 3 MUST be true?

 

[Wiploc]

It's quite apparent now that the speed that we say something is moving is a speed that is relative to something else...thank you.

Cool! You're welcome.

However, that there are no (oh say) mile markers giving us a true speed that need not be relative to other objects (even if such speeds can be measured relative to other objects), that doesn't necessarily entail there is no actual true speed we're moving.

What would a "true" speed look like?

Suppose Jehovah's speed is ten miles an hour different from that of Los Angeles. Does this mean that Los Angeles is "really" going ten miles an hour? In what sense would that speed be more real than speed calculated in any other manner?

I'm reminded of god-based morality that is supposed to be objective even if it's not good for anything.

I say this under the notion that our inability to measure it doesn't necessarily entail there is no it. I'm not convinced there is no true speed.

Agreed. If we believe it, our belief has to be based on something other than our inability to disprove it.

As a layman, I base my belief on the consensus of the experts.

 

[fast]

Cool! You're welcome.

However, that there are no (oh say) mile markers giving us a true speed that need not be relative to other objects (even if such speeds can be measured relative to other objects), that doesn't necessarily entail there is no actual true speed we're moving.

What would a "true" speed look like?

Suppose Jehovah's speed is ten miles an hour different from that of Los Angeles. Does this mean that Los Angeles is "really" going ten miles an hour? In what sense would that speed be more real than speed calculated in any other manner?

I'm reminded of god-based morality that is supposed to be objective even if it's not good for anything.

I say this under the notion that our inability to measure it doesn't necessarily entail there is no it. I'm not convinced there is no true speed.

Agreed. If we believe it, our belief has to be based on something other than our inability to disprove it.

As a layman, I base my belief on the consensus of the experts.

A true speed would probably be extremely fast, like 2 1/2 million mph. I could be way off, but shoot, I can't measure it, but my best guess at this time would be somewhere around the speed in which galaxies are moving.

ETA: correction ... The speed in which our galaxy is moving...um, or the galaxy cluster to which we belong.

 

[Wiploc]

A true speed would probably be extremely fast, like 2 1/2 million mph. I could be way off, but shoot, I can't measure it, but my best guess at this time would be somewhere around the speed in which galaxies are moving.

ETA: correction ... The speed in which our galaxy is moving...um, or the galaxy cluster to which we belong.

I'm confused. What is our galaxy (or cluster) moving 2.5 million mph relative to?

 

[Wiploc]

Fast, you'd be doing me (and anyone else who replies to one of your posts) a favor if you put a blankline between your text and the text you're responding to. That way, the quote and unquote tags are easy to find.

 

[fast]

A true speed would probably be extremely fast, like 2 1/2 million mph. I could be way off, but shoot, I can't measure it, but my best guess at this time would be somewhere around the speed in which galaxies are moving.

ETA: correction ... The speed in which our galaxy is moving...um, or the galaxy cluster to which we belong.

I'm confused. What is our galaxy (or cluster) moving 2.5 million mph relative to?

Well, the thing is, I'm denying that it must necessarily be relative to something at whatever speed we are moving. I'm not saying we aren't moving relative to other things, however. If we could magically place two imaginary and stationary points one mile apart in front of our trajectory, we could measure the speed in which we're moving. Our inability to do such a thing makes it necessary to calculate relative speeds if we want to know how fast we are going. It's apparently recognized that we can calculate a variety of relative speeds; in fact, because we can't determine if there is in fact a truly motionless object, we are without the tools necessary to calculate a true speed. It's the very recognition that we can't do such a thing and the commonplace acceptance that we can only calculate speeds relative to other objects that gives rise to the faulty notion there is no true (or actual) non-relative speed. We are simply lacking a basis for calculation, but given that we know that, shouldn't we recognize that that is simply a barrier to doing the math?

 

[zorq]

What is an example of a valid non-deductive argument?

1 Almost all dogs are less than 1000 kg
2 Rex is a dog.
3 Rex is probably less than 1000 kg

If 1 and 2 are true, then 3 MUST be true?

Yep

 

[steve_bnk]

A true speed would probably be extremely fast, like 2 1/2 million mph. I could be way off, but shoot, I can't measure it, but my best guess at this time would be somewhere around the speed in which galaxies are moving.

ETA: correction ... The speed in which our galaxy is moving...um, or the galaxy cluster to which we belong.

I'm confused. What is our galaxy (or cluster) moving 2.5 million mph relative to?

Well, the thing is, I'm denying that it must necessarily be relative to something at whatever speed we are moving. I'm not saying we aren't moving relative to other things, however. If we could magically place two imaginary and stationary points one mile apart in front of our trajectory, we could measure the speed in which we're moving. Our inability to do such a thing makes it necessary to calculate relative speeds if we want to know how fast we are going. It's apparently recognized that we can calculate a variety of relative speeds; in fact, because we can't determine if there is in fact a truly motionless object, we are without the tools necessary to calculate a true speed. It's the very recognition that we can't do such a thing and the commonplace acceptance that we can only calculate speeds relative to other objects that gives rise to the faulty notion there is no true (or actual) non-relative speed. We are simply lacking a basis for calculation, but given that we know that, shouldn't we recognize that that is simply a barrier to doing the math?

In calculus notation


s = distance
Velocity v = ds/dt or change indistance per change in time.
Acceleration a = dv/dt change invelocity per change in time.

It is more basic. It is not that there can be no absolute zero motion reference frame, it is that if it exists we have no wayto know it.

If you are in deep space in aspaceship, all you can measure is acceleration(change in velocity), using an accelerometer.

 

[Speakpigeon]

If we believe it, our belief has to be based on something other than our inability to disprove it.
As a layman, I base my belief on the consensus of the experts.

A true speed would probably be extremely fast, like 2 1/2 million mph. I could be way off, but shoot, I can't measure it, but my best guess at this time would be somewhere around the speed in which galaxies are moving.

ETA: correction ... The speed in which our galaxy is moving...um, or the galaxy cluster to which we belong.

The notion that the speed of a massive body is somehow absolute seems to be a category error according to the consensus of scientific experts, which in turn seems to point at a disagreement between scientific experts and the way competent speakers use the word "speed", in the case of massive bodies, as the distance traveled divided by the time of travel. But how is distance measured if not relatively to other massive objects? Science says we don't measure the distance between two points of space but between objects. But in competent speech, distance is the extent of space between two objects... or two places. So, the lexical meaning is clear and leaves room enough for the idea of absolute speed, which physicists say doesn't apply to the speed of massive objects. So, can we specify the notion of category error so that both are correct?
EB

 

[Juma]

The notion that the speed of a massive body is somehow absolute seems to be a category error

Nah. Speed is relative. But that is maybe not what you ment...

the way competent speakers use the word "speed", in the case of massive bodies, as the distance traveled divided by the time of travel.

Who are these "competent speakers"?
Seems you speak of something else than speed at a specific time moment. Som sort of "mean speed over land" or something line that.

But how is distance measured if not relatively to other massive objects? Science says we don't measure the distance between two points of space but between objects.

Eh, again. Who says this?

But in competent speech, distance is the extent of space between two objects... or two places. So, the lexical meaning is clear and leaves room enough for the idea of absolute speed, which physicists say doesn't apply to the speed of massive objects.

What does these "physicist" really say? Cause what you say doesnt make sense.

You can always talk about speed as the rate of change relative time of anything, really.

That real objects cannot have higher speed than c is a totally different matter.

I think your problem stems from the way we measure distance: in time units of light flight.