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Is History a Science?
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Poll Question: Is history a science?
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    Posted: 12-Sep-2006 at 05:41
 
Originally posted by Quetzalcoatl

Originally posted by Omar al Hashim

Originally posted by Quetzalcoatl

Originally posted by gcle

Newton's Laws of Motion aren't even true, just approximations that are applicable in a limited range of circumstances.
Shouldn't be put this way. Newton Laws of motion are true within  certain limits, but no longer applicable outside the boundaries of the relevent parameters. Those limits are usually well within what a human being experienced normally (light effects excluded). In fact, all laws are only applicable within certain limits.

Except for the fact that gcle put it far more accurately and eloquently than you, exactly what is the difference between what you and he said?
 
He is just eloquent; I'm accurate.
 
He claimed: Newton's laws aren't true but are only approximations: not true, only approximations.
 
The truth: Newton's Laws are valid within certain limits, no longer applicable outside  those limits: the truth is limited.
'Valid' raises a different issue. An approximation may well be valid. In fact it may well be valid to make a decision based on an assumption known to be only probable.
 
 
Practical models are approximations of the Laws. The Laws themselves aren't approximations, but are formulated under certain ideal conditions (the limits). Get it now!
The Laws as formulated are of course not approximations: they claim to be accurate. However in any circumstances they are only approximately true, though within a certain range the difference is negligible.
 
They are not true within certain limits and untrue outside them.  If they were then it would be possible to say what those limits are, and it isn't.
 
The relativistic laws that have been accepted in their place are more accurate over all ranges, though the difference may not be measurable with our instruments. To assume however that the relativistic equations will not ever be shown to be themselves only approximately true would be to go too far.
 
 
No wonder I prefer science over History. Science is fact; I can get Gcle cornered anytime, and put an end to his incessant riposte.  I really need to stop being argumentative, it's a sign of weakness.
Wink
  
 
Someone else raised the interesting question of whether considering the formation of the solar system is a historical study or a scientific one. It is, it seems to me, obviously both. So the distinction is a false one.
 
Both science and history study the past, because there is nothing to study except the past. 'Science' however implies a methodology that historians may or may not follow.
 


Edited by gcle2003 - 12-Sep-2006 at 05:46
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Posts: 952 		  Quote Paul Quote  Post ReplyReply Direct Link To This Post Posted: 12-Sep-2006 at 05:54
Originally posted by Quetzalcoatl

 @Paul

 No Paul, this is not the definition of science. Science is about observations; procedures; readings and measurements; calculation and theory; and, eventually, debates and conclusions. Science has its flaws, however.

 
Science is about finding the results, the corperation funding the research is paying you to find.
 
 
If a cosmetic giant organises major research into whether it's creams stop aging....A cigarette company conducts major tests to find a connection between smoking and cancer.... A fast food company tests to see if junk food is harmful to kids........ What's the chances of them finding anti aging cream is phony, smoking kills you and fast food makes you fat?
 
 
 


Edited by Paul - 12-Sep-2006 at 06:02
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Posts: 984 		  Quote Quetzalcoatl Quote  Post ReplyReply Direct Link To This Post Posted: 12-Sep-2006 at 06:55
Quetzalcoatl:
Interesting, although your contradictory arguments are rather difficult to decipher, I have discovered that, you are wrong!
But for the opposite reason, thus I was wrong too. Newtons 2nd Law is saved by simply redefining it.

The most common form you will find Newtons 2nd law in is F=ma, which I note is not the one you quoted above. The one you quoted above does work at relatavistic speeds.

If we were working with F=ma then in reality (or relativity)

Which when v << c is approximately F=ma. (Or the limit as v tends to 0 is F=ma)

But if we redefine Newtons Law to this:

It holds!

But for now I think I will leave this argument where it is. If you wish to start a thread about how all science is mearly a description of the real world I'd be happy to frequent it, but lets stop destroying dear Aelfgifu's thread.
 
Contradictory! No too complicated for you to comprehend, nevertheless accurate.
 
Laws are constantly refined to stay Laws. If a contradiction is found the law is invalidated or becomes at best Laws-approximation (not proper Laws, especially if there are applications). Laws are ideal models, unless discredited, cram that in your head. Laws-approximation are merely convenient in practice, but theoretically flawed.
 
That's why F=ma or F=m(dv/dt) is no longer considered as Newton's second law, but a law-approximation. The formula was refined the new formula become Newton's 2nd law.
 
A law by definition is not an approximation, if found to be so, it is no longer a law. Full stop. End of discussion.
 
 
 
 


Edited by Quetzalcoatl - 12-Sep-2006 at 07:27
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However in any circumstances they are only approximately true, though within a certain range the difference is negligible.
 
They are not true within certain limits and untrue outside them.  If they were then it would be possible to say what those limits are, and it isn't.
It's the other way around.
Some people confuse engineering with physics and other theoretical sciences. A physical law is true or not (where truth must be understood in the scientific paradigm - check Hume, Popper, Kuhn, Lakatos). It's an approximation in a metaphorical sense, i.e. that we try to grasp how reality is, thar our view is not confirmed, but not in the particular sense of an enginerring or mathematical (in computation, inherent measuring errors, etc.) approximation.
When in these theoretical sciences a law is stated, somewhere in its full text (enounce, proof, etc.) you will see fragments of texts like "let's assume a constant force applied", "for an epsilon small enough" (a note here - this is an approximation, but not of the law itself but of a part of it which is specified as such - hope you can make the difference) etc.. These are actually restrictions which specify when the current statements are considered (proven) true and when they are not. The law itself works under such assumptions (restrictions), not to mention the "invisible" restrictions given by definitions, axioms, concepts the law operates with. On such concept which makes the difference between Newton's laws and SR is "mass". If we add QM then we see even "force" is not that simple to be defined.
 
Newton's laws, as any scientific laws, are constantly validated or invalidated by empyrical observation, therefore adding the aforementioned supplimentary restrictions. Theories may eventually be absolutely torn down by future evidences (like the earlier models of the atom or the nature of comets).

F = dp/dt is no trick, this formula is even suggested by Newton's original text, where the word "mass" is no part of it. F = dp/dt was known before 20th century.
First law, of inertia, is true under SR.
Even his second law, is true under SR with the supplementary restriction: "where B is insignificant" i.e. where v << c.
It's an overstatment to say "Newton's laws are no longer valid in modern physics". They hold under special circumstances or in new formulas, adapting his concepts to our current understanding.
 
Now coming back at history, a capital difference between history and physics (soft and hard sciences, if you want) is the value of the discourse. In physics the discourse is null, in history can be persuading (and here many quicksands can be listed: appeals to authority, rhetoric, abusing analogies and parallelisms, false dilemmas, etc.)
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Eeehrm, much as I enjoy your little fight here, it is rather off-topic. Please a bit more history and a bit less formulas. I hoped I never had to see those again after school.... Confused

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Posts: 984 		  Quote Quetzalcoatl Quote  Post ReplyReply Direct Link To This Post Posted: 12-Sep-2006 at 19:00
Originally posted by Chilbudios

It's the other way around.
Some people confuse engineering with physics and other theoretical sciences. A physical law is true or not (where truth must be understood in the scientific paradigm - check Hume, Popper, Kuhn, Lakatos). It's an approximation in a metaphorical sense, i.e. that we try to grasp how reality is, thar our view is not confirmed, but not in the particular sense of an enginerring or mathematical (in computation, inherent measuring errors, etc.) approximation.
When in these theoretical sciences a law is stated, somewhere in its full text (enounce, proof, etc.) you will see fragments of texts like "let's assume a constant force applied", "for an epsilon small enough" (a note here - this is an approximation, but not of the law itself but of a part of it which is specified as such - hope you can make the difference) etc.. These are actually restrictions which specify when the current statements are considered (proven) true and when they are not. The law itself works under such assumptions (restrictions), not to mention the "invisible" restrictions given by definitions, axioms, concepts the law operates with. On such concept which makes the difference between Newton's laws and SR is "mass". If we add QM then we see even "force" is not that simple to be defined.
 
Newton's laws, as any scientific laws, are constantly validated or invalidated by empyrical observation, therefore adding the aforementioned supplimentary restrictions. Theories may eventually be absolutely torn down by future evidences (like the earlier models of the atom or the nature of comets).

F = dp/dt is no trick, this formula is even suggested by Newton's original text, where the word "mass" is no part of it. F = dp/dt was known before 20th century.
First law, of inertia, is true under SR.
Even his second law, is true under SR with the supplementary restriction: "where B is insignificant" i.e. where v << c.
It's an overstatment to say "Newton's laws are no longer valid in modern physics". They hold under special circumstances or in new formulas, adapting his concepts to our current understanding.
 
Now coming back at history, a capital difference between history and physics (soft and hard sciences, if you want) is the value of the discourse. In physics the discourse is null, in history can be persuading (and here many quicksands can be listed: appeals to authority, rhetoric, abusing analogies and parallelisms, false dilemmas, etc.)
 
Finally, someone who understands. And guess what: a Frenchman. You french Chilb?


Edited by Quetzalcoatl - 12-Sep-2006 at 19:01
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Posts: 7035 		  Quote gcle2003 Quote  Post ReplyReply Direct Link To This Post Posted: 13-Sep-2006 at 05:26
 
Originally posted by Chilbudios

However in any circumstances they are only approximately true, though within a certain range the difference is negligible.
 
They are not true within certain limits and untrue outside them.  If they were then it would be possible to say what those limits are, and it isn't.
It's the other way around.
Some people confuse engineering with physics and other theoretical sciences. A physical law is true or not (where truth must be understood in the scientific paradigm - check Hume, Popper, Kuhn, Lakatos).
Hume and Popper certainly deny absolute truth is knowable. In that school, a statement is only scientific if it can be falsified. If it is absolutely true - cannot be falsified - then it is not scientific.
 
It's an approximation in a metaphorical sense, i.e. that we try to grasp how reality is, thar our view is not confirmed, but not in the particular sense of an enginerring or mathematical (in computation, inherent measuring errors, etc.) approximation.
When in these theoretical sciences a law is stated, somewhere in its full text (enounce, proof, etc.) you will see fragments of texts like "let's assume a constant force applied", "for an epsilon small enough" (a note here - this is an approximation, but not of the law itself but of a part of it which is specified as such - hope you can make the difference) etc.. These are actually restrictions which specify when the current statements are considered (proven) true and when they are not.
 
By the very authorities you quote, scientific assertions, whether you call them laws or not, cannot be proven true. They can only (Popper) be proven false. If you think what you are saying is proven true, then you're into metaphysics and religion, not science.
 
The law itself works under such assumptions (restrictions), not to mention the "invisible" restrictions given by definitions, axioms, concepts the law operates with. On such concept which makes the difference between Newton's laws and SR is "mass". If we add QM then we see even "force" is not that simple to be defined.
 
Newton's laws, as any scientific laws, are constantly validated or invalidated by empyrical observation, therefore adding the aforementioned supplimentary restrictions.
'Valid' is another concept - an engineering one if you will. It is frequently perfectly valid to make an assumption that you know is untrue. Thus it was perfectly valid in calculating the trajectory of an 18th century naval gun on the assumption that the earth was flat. That won't work for ICBMs, but it is perfectly valid to calculate their trajectory on the assumption the earth is spherical, which it is known not to be.
 
So validity has nothing to do with it.
 
 Theories may eventually be absolutely torn down by future evidences (like the earlier models of the atom or the nature of comets).

F = dp/dt is no trick, this formula is even suggested by Newton's original text, where the word "mass" is no part of it. F = dp/dt was known before 20th century.
Yes, but then p was assumed proportional to velocity which makes a huge difference. 'p' in the 19th century was a different concept to that post-Einstein.
 
The distinction between Newton's original formulation and the revised version is that mass was assumed by him (and anyone else around at the time) to be independent of velocity. So you could take it to the left of the derivative: F=mdv/dt with m constant. If mass varies with speed as we would now hold then m has to be part of the derivative F=dp/dt.
 
But that is a major change in the law. It isn't Newton's Law any more.
 
Incidentally Newton didn't even write F=mdv/dt since that notation for the derivative hadn't been invented yet.
 
First law, of inertia, is true under SR.
Even his second law, is true under SR with the supplementary restriction: "where B is insignificant" i.e. where v << c.
Nope. It's still only an approximation as long as it is expressed as mdv/dt, which is how Newton expressed it.
 
It's an overstatment to say "Newton's laws are no longer valid in modern physics". They hold under special circumstances or in new formulas, adapting his concepts to our current understanding.
Well if you change them then you've changed them. They're not his concepts any more, are they? Duh!
 
Now coming back at history, a capital difference between history and physics (soft and hard sciences, if you want) is the value of the discourse. In physics the discourse is null, in history can be persuading (and here many quicksands can be listed: appeals to authority, rhetoric, abusing analogies and parallelisms, false dilemmas, etc.)
I'm not sure what you mean by discourse.
 


Edited by gcle2003 - 13-Sep-2006 at 05:48
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Originally posted by gcle2003

Hume and Popper certainly deny absolute truth is knowable. In that school, a statement is only scientific if it can be falsified. If it is absolutely true - cannot be falsified - then it is not scientific.
 Some observations:
- who's talking of absolute truth?
- you can't state anything without an axiomatic foundation. Axioms are unfalsifiable by definition. If you put all axioms down you'll see yourself unable to state anything. Anything at all. Moreover Popper's understanding of falsifiable as scientific was challenged by Kuhn and Lakatos.
- what is truth anyway? You're presupposing logical truth (as in prepositional logic, for instance), but I was specifying clearly enough truth as understood in the scientific paradigm. If you want to understand the scientific truth, you may want to read other modern logicians (Tarski, for instance) and get aquainted with a modern concept of truth as correspondence between two certain realities (reality here means a populated space, a mathematical space modelling something, not physical reality).
 
By the very authorities you quote, scientific assertions, whether you call them laws or not, cannot be proven true. They can only (Popper) be proven false. If you think what you are saying is proven true, then you're into metaphysics and religion, not science.
The only scientific assertions are the hypotheses. The other statemnts are "proven true" as the scientific method requires it, by incomplete induction i.e.
1) P(1) <- hypothesis
2) P(2) ... P(k, where k is finite) <- confirming the hypothesis
===
P(n) <- conclusion
They are true until proven otherwise, i.e. until !P(m) where m is finite > k.
 
Concluding they are not true ("proven true"), results to self-annilihation. Who cares what Popper said if he can't value his own statements. LOL
 
'Valid' is another concept - an engineering one if you will. It is frequently perfectly valid to make an assumption that you know is untrue. Thus it was perfectly valid in calculating the trajectory of an 18th century naval gun on the assumption that the earth was flat. That won't work for ICBMs, but it is perfectly valid to calculate their trajectory on the assumption the earth is spherical, which it is known not to be.
 
So validity has nothing to do with it.
Valid is an english word. I'm not talking about valid/invalid/sound/unsound. But valid as well-grounded, justifiable (check a dictionary). Your impetus to deny what others write overcomes the undestanding. Chill down!
 
Yes, but then p was assumed proportional to velocity which makes a huge difference. 'p' in the 19th century was a different concept to that post-Einstein.
 
The distinction between Newton's original formulation and the revised version is that mass was assumed by him (and anyone else around at the time) to be independent of velocity. So you could take it to the left of the derivative: F=mdv/dt with m constant. If mass varies with speed as we would now hold then m has to be part of the derivative F=dp/dt.
 
But that is a major change in the law. It isn't Newton's Law any more.
 
Incidentally Newton didn't even write F=mdv/dt since that notation for the derivative hadn't been invented yet.
 The law is still working in its original formulation: Mutationem motus proportionalem esse vi motrici impressae, & fieri secundum lineam rectam qua vis illa imprimitur.
The only change is in what mutationem motus means (and not fully, conceptually they are almost the same in classical physics and SR, is just that in SR the mass is dependent on velocity). But I already said that.
 
As for derivative, you seem to have no idea of concepts like variation which were well-known and understood at Netwon's time. There wasn't a mathematical operator, but I clearly stated "suggested" not "wrote".
 
Nope. It's still only an approximation as long as it is expressed as mdv/dt, which is how Newton expressed it.
To say "F = m*a for v small enough and for m large enough" is not an approximation, is a precise statement. To say "F = m*a" is an approximation. Newton's own formula (as you can read it above) is not an approximation even if we read it in SR. Only when we write "p = m*v" with no further details, then it becomes an approximation.
 
Well if you change them then you've changed them. They're not his concepts any more, are they? Duh!
I am saying Newton's laws as enounces written in our modern textbooks, you're talking about his concepts as he owns them or something. 
 
 
I'm not sure what you mean by discourse.
 
 
Check definitions 3 and 5.


Edited by Chilbudios - 13-Sep-2006 at 07:32
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Posts: 984 		  Quote Quetzalcoatl Quote  Post ReplyReply Direct Link To This Post Posted: 13-Sep-2006 at 07:51
But that is a major change in the law. It isn't Newton's Law any more
 
Wrong.  You are confused. The Law changes accordingly, but retained the same name (this is where your confusion stemmed). The law as formulated by Newton is no longer Newton's 2nd Law, but a Law-approximation.
 
Initial Newton's 2nd law = Law-approximation.
 
Modern Newton's 2nd law = Law.
 
future = ?
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Posts: 984 		  Quote Quetzalcoatl Quote  Post ReplyReply Direct Link To This Post Posted: 13-Sep-2006 at 07:53
Incidentally Newton didn't even write F=mdv/dt since that notation for the derivative hadn't been invented yet.
Newton pioneered the concept. Derivative is simply the gradient.
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Posts: 1900 		  Quote Chilbudios Quote  Post ReplyReply Direct Link To This Post Posted: 13-Sep-2006 at 07:56
Originally posted by Quetzacoatl

You french Chilb?
No Tongue
 
Wrong.  You are confused. The Law changes accordingly, but retained the same name (this is where your confusion stemmed). The law as formulated by Newton is no longer Newton's 2nd Law, but a Law-approximation.
 
Initial Newton's 2nd law = Law-approximation.
 
Modern Newton's 2nd law = Law.
 
future = ?
Not quite. Modern Newton's 2nd law still says F = m*a. There's also such a law written relativistically. But also Newton 2nd law says F = dp/dt.
I prefer F = dp/dt for two reasons:
a) is more accurate (and wide in appliance)
b) the original formula suggests a variation in time. Therefore we need a /dt to illustrate it.


Edited by Chilbudios - 13-Sep-2006 at 07:58
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Originally posted by Aelfgifu

 
It is therefore my opinion that History can be considered a science in its own right.
 
What do you think?


Read Carr's book:''What is history?"
You will find the answer there.
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Originally posted by nikodemos

 
Originally posted by Aelfgifu

It is therefore my opinion that History can be considered a science in its own right.
 
What do you think?
 


Read Carr's book:''What is history?"
You will find the answer there.
 
 
 
LOL
Thanks for the advice. I t was however not my intention to get a definitive answer, (which is impossible anyway)but to get a discussion about the subject, because being in a discussion often makes the various points of view or options more clear.
I have (had to) read a number of books about it in the third year of my study, which I detested at the time, and I have made up my mind already. I was just wondering what the overall thoughts on AE would be about this, as everybody here cares about history.


Edited by Aelfgifu - 13-Sep-2006 at 10:55

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Originally posted by Chilbudios

 
 Not quite. Modern Newton's 2nd law still says F = m*a. There's also such a law written relativistically. But also Newton 2nd law says F = dp/dt.
I prefer F = dp/dt for two reasons:
a) is more accurate (and wide in appliance)
b) the original formula suggests a variation in time. Therefore we need a /dt to illustrate it.
 
I have to insist Newton's 2nd law is no longer associated (ideally, not in practice though) with the formula F=ma (this in fact is merely the formula to a close approximation, applicable when m is taken as a constant and v is much less than c.)
 
Newton's 2nd law, not formulated. (and do not confuse a formula and a law generally defined or redefined, ok. a formula is the mathematical representation of a law, not the law itself. Law can be the consequence of mathematical symmetries in nature.) 
 
The rate of change of the momentum of a body is directly proportional to the net force acting on it, and the direction of the change in momentum takes place in the direction of the net force.
 
They definition is quite generalise. As the momentum it can be adapted to incorporate the changing mass in relativistic terms as well as high speed elasticity. So, Newton just assume m is a constant when he formulated the law. If He knew about relativity, the formula would be otherwise. The general definition doesn't change, however. Formula is  not equal to a law, just a representation of a law.
 
Below is an extract to understand the changing nature of the formula of a law.
 
 
Extract
 

Some extremely important laws are simply definitions. For example, central law of mechanics F = dp/dt (Newton's second "law" of mechanics) is not a law at all but is a mathematical definition of force (introduced first by Newton himself). The principle of least action (or principle of stationary action),Schroedinger equation, Heisenberg uncertainty principle, and a few other laws fall into this category.

Most of the other laws are mathematical consequences of various mathematical symmetries (see Emmy Noether theorem as a proof of this). For example, conservation of energy is a consequence of the shift symmetry of time (no time moment is different from any other), while conservation of momentum is a consequence of the symmetry (homogeneity) of space (no place in space is different from any other). Indistinguishability of similar particles (say, electrons, or photons) results in the Dirac and Bose statistics which in turn results in the Pauli exclusion principle for fermions and in Bose condensation for bosons. Symmetry between time and space coordinate axis results in Lorentz transformations which in turn results in special relativity theory. Symmetry between inertial and gravitational mass results in general relativity, and so on.



Edited by Quetzalcoatl - 13-Sep-2006 at 20:59
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I have to insist Newton's 2nd law is no longer associated (ideally, not in practice though) with the formula F=ma (this in fact is merely the formula to a close approximation, applicable when m is taken as a constant and v is much less than c.)
Associated by whom?
and this is not a solitary example.
 
I already agreed that Newton's formula rather points out to dp/dt than to m*a. Yet you can't say Newton's law is rather dp/dt than m*a, because one can find many instances (as many as you want) where m*a formula is given.
 
a formula is the mathematical representation of a law, not the law itself. Law can be the consequence of mathematical symmetries in nature
There are no laws or mathematics in the nature. They are human tools. Ask nature if you don't believe me Tongue
 
 
 
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Originally posted by Quetzalcoatl

But that is a major change in the law. It isn't Newton's Law any more
 
Wrong.  You are confused. The Law changes accordingly, but retained the same name (this is where your confusion stemmed). The law as formulated by Newton is no longer Newton's 2nd Law, but a Law-approximation.
 
Initial Newton's 2nd law = Law-approximation.
 
Modern Newton's 2nd law = Law.
 
future = ?
 
That's just silly. You can alter Pythagoras' Theorem to apply to other than Euclidean surfaces, but that doesn't mean you can call the new one 'Pythagoras' Theorem any more.
 
Newton's Law was Newton's Law. Change it and it's not Newton's Law anymore. If I do a version of the Monal Lisa in modern dress, then it's not Leonardo's Mona Lisa, is it?
 
What don't you understand about 'change'?
 


Edited by gcle2003 - 14-Sep-2006 at 06:54
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Originally posted by Chilbudios

Originally posted by gcle2003

Hume and Popper certainly deny absolute truth is knowable. In that school, a statement is only scientific if it can be falsified. If it is absolutely true - cannot be falsified - then it is not scientific.
 Some observations:
- who's talking of absolute truth?
Anybody who says something is not an approximation. If it's true, but not approximately true, it must be absolutely true.
 
- you can't state anything without an axiomatic foundation. Axioms are unfalsifiable by definition.
Unfalsifiable by deduction, yes. However, an axiom can be false if it not empirically true. I can accept as an axiom that the earth is flat and certain conclusions follow from that (like Pythagoras' Theorem applies on its surface). However, empirically, the axiom is false.
 
 
 
 If you put all axioms down you'll see yourself unable to state anything. Anything at all.
I don't put down axioms. Any old axioms can be the basis of a deductive system, and they cannot be proven wrong within that system. However, that is absolutely no guarantee at all that the axioms apply to the real world. They may do so of course. They may do within the limits of our measurements. Whether they do so absolutely can never be proven.
 
 
Moreover Popper's understanding of falsifiable as scientific was challenged by Kuhn and Lakatos.
So? It's still the most commonly accepted scientific paradigm. You conceive a hypothesis, and you experiment in order to disprove it. If you fail to disprove it it remains an acceptable hypothesis, until that day in the future when it like all scientific hypotheses is disproven.
 
 
- what is truth anyway? You're presupposing logical truth (as in prepositional logic, for instance), but I was specifying clearly enough truth as understood in the scientific paradigm.
No I wasn't, I was talking about empirical truth. And no you aren't. See above.
 
If you want to understand the scientific truth, you may want to read other modern logicians (Tarski, for instance) and get aquainted with a modern concept of truth as correspondence between two certain realities (reality here means a populated space, a mathematical space modelling something, not physical reality).
I've read Tarski. If you redefine 'truth' to mean something different from what it has traditionally meant then of course you can go anywhere you like.
 
What there has basically been over the centuries since Hume is a rearguard action being fought by metaphysicians who cannot stand the thought that truth - empirical truth - about the real world is forever unknowable. If in that rearguard action a few definitions have to be changed - well, they don't mind that as long as they can end up saying "We know that what we know is true".
 
The religious mindset is difficult to defeat.
 
By the very authorities you quote, scientific assertions, whether you call them laws or not, cannot be proven true. They can only (Popper) be proven false. If you think what you are saying is proven true, then you're into metaphysics and religion, not science.
The only scientific assertions are the hypotheses. The other statemnts are "proven true" as the scientific method requires it, by incomplete induction i.e.
1) P(1) <- hypothesis
2) P(2) ... P(k, where k is finite) <- confirming the hypothesis
===
P(n) <- conclusion
They are true until proven otherwise, i.e. until !P(m) where m is finite > k.
 
There you go making 'truth' relative. If they're proven untrue then they were untrue all along (assuming we are talking about universal propositions: the statement I am 55 years old is no longer true, though it was once, because reality itself has changed).
 
Unless they are such time-dependent statements, you cannot say something is false in 2006 but was true in 1200. It can't have been true that the planets revolved around th earth in 1200 if it is true in 2006 that they revolve around the sun.
 
That way madness lies.
 
Concluding they are not true ("proven true"), results to self-annilihation. Who cares what Popper said if he can't value his own statements. LOL
 
'Valid' is another concept - an engineering one if you will. It is frequently perfectly valid to make an assumption that you know is untrue. Thus it was perfectly valid in calculating the trajectory of an 18th century naval gun on the assumption that the earth was flat. That won't work for ICBMs, but it is perfectly valid to calculate their trajectory on the assumption the earth is spherical, which it is known not to be.
 
So validity has nothing to do with it.
Valid is an english word.
I'm aware of that.
 
 I'm not talking about valid/invalid/sound/unsound. But valid as well-grounded, justifiable (check a dictionary). Your impetus to deny what others write overcomes the undestanding. Chill down!
 
Yes, but then p was assumed proportional to velocity which makes a huge difference. 'p' in the 19th century was a different concept to that post-Einstein.
 
The distinction between Newton's original formulation and the revised version is that mass was assumed by him (and anyone else around at the time) to be independent of velocity. So you could take it to the left of the derivative: F=mdv/dt with m constant. If mass varies with speed as we would now hold then m has to be part of the derivative F=dp/dt.
 
But that is a major change in the law. It isn't Newton's Law any more.
 
Incidentally Newton didn't even write F=mdv/dt since that notation for the derivative hadn't been invented yet.
 The law is still working in its original formulation: Mutationem motus proportionalem esse vi motrici impressae, & fieri secundum lineam rectam qua vis illa imprimitur.
The only change is in what mutationem motus means (and not fully, conceptually they are almost the same in classical physics and SR, is just that in SR the mass is dependent on velocity). But I already said that.
I know it's the only change. But for Newton 'motus' meant 'speed', not what we would call momentum. Granted he didn't actually use the concept of 'mass' but he was saying that change in speed was proportional to the force applied - in modern terminology dv/dt = kF. He was quite obviously NOT saying d(mv)/dt = kF, because he had no 'm' and therefore no 'p'.
 
In any case you write 'the only change is in what mutationem motus means and i would agree with that. But a change is a change is a change, and this is a fundamental change, only emphasised in a latterday attempt to square the law with SR, something which it is quite nonsensical to attribute to Newton.
 
Actually what we have again here is that same reluctance that I described above to admit science was and always is essentially untrue. Abandon that belief and essentially you abandon science for metaphysics.
 
 
As for derivative, you seem to have no idea of concepts like variation which were well-known and understood at Netwon's time.
Don't be silly.
 
 
There wasn't a mathematical operator, but I clearly stated "suggested" not "wrote".
 
Nope. It's still only an approximation as long as it is expressed as mdv/dt, which is how Newton expressed it.
To say "F = m*a for v small enough and for m large enough" is not an approximation, is a precise statement.
Oh, come on! Yes if i say 'X is approximately true' that is a precise statement that X is approximately true. But that goes nowhere.
It's X that is approximate, not the statement about X.
 
To say "F = m*a" is an approximation. Newton's own formula (as you can read it above) is not an approximation even if we read it in SR. Only when we write "p = m*v" with no further details, then it becomes an approximation.
 
Well if you change them then you've changed them. They're not his concepts any more, are they? Duh!
I am saying Newton's laws as enounces written in our modern textbooks, you're talking about his concepts as he owns them or something. 
 
Of course I am. The phrase 'Newton's Law' means the law that Newton proposed. It doesn't mean some latterday variation of it. (Note what I said about the Mona Lisa above.) 'Newton's law' doesn't mean Newton owns it, but then 'Shakespeare's Hamlet' doesn't mean Shakespeare owns Hamlet.
 
But when Charles lamb bowdlerised Hamlet the way he did, the result was no longer Shakespeare's Hamlet, but  Lamb's Hamlet.
 
When Riemann generalised Euclid's geometry by dropping the fifth axiom, no-one went on calling it 'modern Euclidean geometry' as opposed to 'ancient Euclidean geometry'. We call it 'Riemannian geometry'.
 
 
I'm not sure what you mean by discourse.
 
 
Check definitions 3 and 5.


Edited by gcle2003 - 14-Sep-2006 at 07:37
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Posts: 1900 		  Quote Chilbudios Quote  Post ReplyReply Direct Link To This Post Posted: 14-Sep-2006 at 08:42
gcle, it is absurd and crazy to attempt to have a normal debate with you, look how you disrupted a discussion and attempted to counter-point each point your opponents made (in the culture where I come from there's a term describing guys like you which in English would be something like Jack-Against). You have absolutely no feeling of the ridiculous and of the extreme and you're ready to say milk is black just to promote your views and feed your ego with "being right". Moreover, annoyingly (and it's not my first controversy with you), you keep redefining, reformulating and reinterpreting the statements made by others. Learn English, read, educate yourself, the world is not spinning around the way you understand things.
In what you'll read below what you might perceive as condescendence or arrogance is in fact deconstruction and pedagogy (well you may called me arrogant because it's uncalled for, it's my decision and my choice to put a hoped end to large part of the quarrel in this way).
 
 
Anybody who says something is not an approximation. If it's true, but not approximately true, it must be absolutely true.
To corelate this to the subject of the thread - these are the dangers within the "free" discourse. The fallacy presented here is the false dilemma. 
Moreover, the Jack-Against type of the person usually does not read the full answer before replying and denying sentence by sentence, otherwise logically, to deny in such a way he would have to address the nature of truth which was issued in a paragraph further away.
I will now get his fragments in a slightly changed order to corelate them and to avoid much more references up and down.
No I wasn't, I was talking about empirical truth. And no you aren't. See above.
Leaving aside the "no" flavour of the answer (we have here another paradoxical behaviour of the archetype I've described: denying the obvious: my first reply in this thread contained this note: "where truth must be understood in the scientific paradigm"), we notice a new type of truth ... empyrical truth. This is in fact a masked truth of correspondence (which in the next paragraph he'll minimize). Now I will leave the specialist we have here, gcle2003, to expain how an empyrical truth would be absolute or not.
 
I've read Tarski. If you redefine 'truth' to mean something different from what it has traditionally meant then of course you can go anywhere you like.
I cut off the blabla about Hume and religion as it's absolutely of no relevance, deepens the already presented misunderstandings and opens a new paranthesis of endless counterarguing. However, let's remark the "I've read Tarski" (similar to I've read "x" in the capitalism -protestantism debate) while just one paragraph above the "empyrical truth" is emphasized. However it may be that  here is a failure to adapt Tarski's theory of correspondence truth to the Humean paradigm and perhaps also not reading the latter writings of Popper, after he have read Tarski.
 
There you go making 'truth' relative. If they're proven untrue then they were untrue all along (assuming we are talking about universal propositions: the statement I am 55 years old is no longer true, though it was once, because reality itself has changed).
 
Unless they are such time-dependent statements, you cannot say something is false in 2006 but was true in 1200. It can't have been true that the planets revolved around th earth in 1200 if it is true in 2006 that they revolve around the sun.
The dimension of being against sometimes evolves to inimaginable responses (often I use paranthesis not only to add notes but also explanation to prevent misunderstandings, yet I can't anticipate any evolution, certainly an evolution as this one!).
To be or not to be true is not an ontological dilemma, but epistemological, i.e. dependent to the observer (thinker, subject) and his reality (model). It's also absurd to project the trivial true vs false, absolute vs relative dichotomies all over the place.
To explain your example. In the 2006 mindset it is true that planets revolved around the Sun in 1200 and 2006. In the 1200 mindset it was not. It's nothing about being absolute or relative, only about correspondence. That's why I recommended you Kuhn and Lakatos because their additions to the philosophy of science make you undestand better these changes of mindset (Kuhn calls them paradigms).
 
Unfalsifiable by deduction, yes. However, an axiom can be false if it not empirically true. I can accept as an axiom that the earth is flat and certain conclusions follow from that (like Pythagoras' Theorem applies on its surface). However, empirically, the axiom is false.
An axiom can't be false, otherwise is no longer an axiom. An axiom is by definition (also an axiom LOL, yet is more expressive to refer sometimes axioms as conventions) a unprovable non-empyrical always-true statement. Some people make a confusion between axioms and premises, while is true that axioms can be premises, not all premises are axioms. Premises can be both true or false.
 
However, that is absolutely no guarantee at all that the axioms apply to the real world.
That's another axiom (or maybe even a set of axioms if we want to be more accurate and fair) a mindset is free to grant it as true or not.
 
It's still the most commonly accepted scientific paradigm. You conceive a hypothesis, and you experiment in order to disprove it.
Before one attempts an experiment to disprove a hypothesis one need to experiment to confirm it otherwise will be a hypothesis and not a theory. A hypothesis has no truth-weight.
Furthermore, another key aspect of a scientific theory is the prediction. Which means the new theory must be predict other cases outside the initial set/range (get confirmed by more experiments/observations).
The experiments to disprove come afterwards and usually mark the death / mutation of a theory.
 
Ok, enough about scientific method. Also here I end my attempt to show why history (together with other humanities) has a lesser position in the family of science because it allows such kind of argumentations (which we often find in books, sometimes written by scholars with reputation).
 
I'll add few more comments on Newton:
 
I know it's the only change. But for Newton 'motus' meant 'speed', not what we would call momentum. Granted he didn't actually use the concept of 'mass' but he was saying that change in speed was proportional to the force applied - in modern terminology dv/dt = kF. He was quite obviously NOT saying d(mv)/dt = kF, because he had no 'm' and therefore no 'p'.
One advice, learn Latin. Motus means movement, not speed. For Newton, for anyone else. Second advice, try to get on more of Newton's original texts if not read it fully to contemplate properly the semantic possibilities given by this word.
For instance, from
http://www.maths.tcd.ie/pub/HistMath/People/Newton/Principia/Bk1Sect1/PrL1S1.pdf
I'll quote you a piece of text:
Objectio est, quod quantitatum evanescentium nulla sit ultima proportio; quippe qu,antequam evanuerunt, non est ultima, ubi evanuerunt, nulla est. Sed & eodem argumentoque contendi posset nullam esse corporis ad certum locum, ubi motus finiatur, pervenientis velocitatem ultimam: hanc enim, antequam corpus attingit locum, non esse ultimam, ubiattingit, nullam esse. Et responsio facilis est: per velocitatem ultimam intelligi eam, quacorpus movetur, neque antequam attingit locum ultimum & motus cessat, neque postea, sedtunc cum attingit; id iest, illam ipsam velocitatem quacum corpus attingit locum ultimum & quacum motus cessat.
For you or any other takers, please read it and tell me how you translate "motus" here and what would be the modern physical notation for it. As a supplementary exercise, what other physical entities occur in this text, what is the latin word and our current notation for them.
 
much later edit: I've found an even better quote from Newton. Read it LOL:
Quantitas motus est mensura ejusdem orta ex velocitate et quantitate materiae conjunctim.
 
In any case you write 'the only change is in what mutationem motus means and i would agree with that. But a change is a change is a change, and this is a fundamental change, only emphasised in a latterday attempt to square the law with SR, something which it is quite nonsensical to attribute to Newton.
 
The formula given by Newton suggests dp/dt which is valid in SR. No change in that. The whole understanding of Newton and classical physics (the so called newtonian phsyics) however must be adjusted.
In other words, Newton's law, in its own formula, is still valid in SR. Newtonian mechanics is not. The mindset, the paradigm must be changed, but this change is not that radical, therefore a part of the earlier theories retain their validity. F = dp/dt is one of them, likewise Newton's original formula.
 
Don't be silly.
 
The variation is known to European thought since Oresme and his contemporaries. To write laws of variation which today we write using differential operators there's no requirement of knowing how to calculate the derivative of a function. It's not sillyness, it's understanding. Try it someday LOL
 
It's X that is approximate, not the statement about X.
Exactly. F is approximate, not the law (if carefully enounced) about F. To reach the point where we started from, Newton's law is not at all approximate in SR if formulated properly. And even his original formula is a proper one.
 
The phrase 'Newton's Law' means the law that Newton proposed.
Maybe only for you. In modern textbooks Newton's law is F = m*a, not his formula. 
 
When Riemann generalised Euclid's geometry by dropping the fifth axiom, no-one went on calling it 'modern Euclidean geometry' as opposed to 'ancient Euclidean geometry'. We call it 'Riemannian geometry'.
Likewise, we don't call it anymore Newtonian physics, but Relativistic. But even in Riemannian geometry we have some Euclidian axioms, also in the Relativistic physics we have sometimes earlier postulates and laws (like some of the Newton laws in SR).
 
 
 
 
 
 
 
 


Edited by Chilbudios - 14-Sep-2006 at 09:52
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Posts: 1494 		  Quote kotumeyil Quote  Post ReplyReply Direct Link To This Post Posted: 15-Sep-2006 at 02:30
The debate has digressed from the topic. Please discuss whether history is a science or not, or open a new topic about Newton's laws, approximations or whatever.
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Posts: 5697 		  Quote Omar al Hashim Quote  Post ReplyReply Direct Link To This Post Posted: 15-Sep-2006 at 03:44
Attack the argument not the person.

All Science (even history) is mearly an approximation on the real world. Something proposed by a person, whether they call it a law or not, is just a guess at what they observe reality to behave like. It may not truely be like that at all, just from our limited view point it looks like that.


Edited by Omar al Hashim - 15-Sep-2006 at 03:44
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