Opposing theses

[Resha Caner]

So, do we need a "philosophy" forum? I keep looking for a good place to put these questions, but I haven't found it.

 

First, I will apologize if someone thinks this post begins inappropriately, but I think it necessary to demonstrate the intent of my question.

 

Philosophers have wrestled with a problem of logic involving "properties". To say that something has a property entails that something else does not have that property. For example, to say that a geometric figure is "square" because it has four sides implies that a triangle is "not square" because it has three sides.

 

This seems trivial at first, but this logical principle has been used in some very interesting and controversial ways. For example, Godel based a proof of God on this principle. If we say that something has the property of being "physical", then we must accept that something exists which has the property of being "non-physical". And, if we insist that something "non-physical" can be "dead", then we must accept that something "non-physical" can be "alive". And if we accept that a "living non-physical" thing can be finite, then we must accept that a "living non-physical" thing can also be infinite ... and so forth.

 

I have probably bungled Godel's proof, but hopefully you get the point. I think most would agree this "proof" is no proof at all, yet when one sets out to unseat the logic behind it, one encounters many daunting difficulties.

 

So, I finally get to my question: does any theory exist for which there is no way to formulate an opposing theory? (and I mean a reasonable opposing theory)

[thedarkshade]

So, I finally get to my question: does any theory exist for which there is no way to formulate an opposing theory? (and I mean a reasonable opposing theory)

IMO thats not compatible with scientific method.

[Resha Caner]

Could you clarify? Which part do you think is incompatible?

[thedarkshade]

Well every theory has to be falsifiable.

[Mokele]

Take "physical" and "non-physical". The latter category contains no items, no matter what some may imagine.

[Resha Caner]

Well every theory has to be falsifiable.

 

Even if you can falsify one theory, it does not mean you can fomulate another to take its place. I think we are agreeing, but I don't want to be presumptive.

 

The Bayesians have the idea of the "catch-all". It represents those theories that oppose the one in question, but does not attempt to formulate that opposition. It seems to me that stating any theory entails that an opposing theory can be formulated.

 

Take "physical" and "non-physical". The latter category contains no items, no matter what some may imagine.

 

That was only an example. I didn't mean it to be the main thrust of the discussion. Regardless, I don't think I would agree with you. I wouldn't say that "non-physical" contains no items. Rather, discerning if any items exist is outside the realm of science. You would need to "know" the non-physical by other means. But that is a very philosophical discussion. I don't really want to go there.

[John Cuthber]

You say "If we say that something has the property of being "physical", then we must accept that something exists which has the property of being "non-physical". "

but that's an assertion it isn't supported by evidence and I don't see why it is true.

The property "physical" isn't anything special so lets try a different, less esoteric property "not my sister".

Everything has the property of being "not my sister" and nothing has the property "not(not my sister)" because I don't have a sister.

Just because something exists there is no reason to concede that it's converse exists.

 

It seems your idea is based on an unproven (and aparently false) premise.

Also you say

"And, if we insist that something "non-physical" can be "dead"...

OK, but I don't insist on that, in fact I rather doubt it. The concept of "green and yellow striped" exists but isn't physical. I don't see how "green and yellow striped" can be dead.

[Klaynos]

I'd say "green and yellow striped" was physical, either there's some dye in the material, or it's some photonic crystal (or maybe some other metamaterial), I think we need a better definition of physical, the one I use is "falls within the physical theories that currently exist, or experimental evidence" So the only things which are not-physical are those that exist in peoples imaginations that cannot exist in reality due to whatever reason...

 

I also don't see how you could "know by other means" there's only 4 ways things interact with other things, (the 4 fundamental forces), our senses are applications of two of these (gravity and EM), so how do you "know" something that you can't possibly interact with it because if you could interact with it it'd be physical?

[Resha Caner]

I knew I shouldn't have used that example. Remember, it's an example. The point was to ask if all theories necessarily imply an opposing theory.

 

- - -

 

For those interested in the example, let me defer you to these two sites:

 

http://plato.stanford.edu/entries/physicalism

http://en.wikipedia.org/wiki/G%C3%B6del's_ontological_proof

 

And, let me clarify one point. This is an issue of logic, not of empiricism. Whether John's sister exists (and what evidence we have for or against) is a whole other question. The question is whether assigning something a property entails that something else does not have the property.

 

I was not trying to claim this entailment. I was asking a question. In the Stanford entry on physicalism you will see that Hume proposed a solution to the problem, and I am inclined to accept his solution (even though I'm no fan of Hume). If one accepts his solution, does this mean it would be possible to formulate a scientific theory that has no opposing theory? That seems illogical to me ... so maybe I should reject Hume altogether.

[D H]

Resha, could you clarify the issue you are trying to raise? I see several possibilities:

1. Are you talking about two inherently untestable theses?
    
   In this case, who cares? IMHO, both are absolutely worthless philosophical rambling. (Now ask me what I really think.)
    
    
    
   
2. Are you talking about two different theses that predict different outcomes for the same experiment which hasn't been performed?
    
   Here the jury is out. Neither can be deemed better (or valid) until some experiment is performed.
    
    
    
   
3. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A sometimes but with thesis B other times?
    
   Here the jury might still be out. An experiment that yields different results at different times is not a good experiment. The experiment itself might be in need of an update. If the experimental results are indeed valid, I would venture that both theses have been falsified.
    
    
    
   
4. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A always?
    
   This one is easy: The thesis that matches reality wins, regardless of how "ugly" it is.
    
    
    
   
5. Are you talking about two different theses that predict the same outcome for all experiments?
    
   Here "beauty" does come into play. This is why special relativity is taught rather than Lorentz ether theory, even though the two are indistinguishable in terms of predicted outcomes.
    
    
    
   
6. Are you talking about something else entirely?

[Resha Caner]

Resha, could you clarify the issue you are trying to raise? I see several possibilities:

1. Are you talking about two inherently untestable theses?
    
   In this case, who cares? IMHO, both are absolutely worthless philosophical rambling. (Now ask me what I really think.)
    
    
    
   
2. Are you talking about two different theses that predict different outcomes for the same experiment which hasn't been performed?
    
   Here the jury is out. Neither can be deemed better (or valid) until some experiment is performed.
    
    
    
   
3. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A sometimes but with thesis B other times?
    
   Here the jury might still be out. An experiment that yields different results at different times is not a good experiment. The experiment itself might be in need of an update. If the experimental results are indeed valid, I would venture that both theses have been falsified.
    
    
    
   
4. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A always?
    
   This one is easy: The thesis that matches reality wins, regardless of how "ugly" it is.
    
    
    
   
5. Are you talking about two different theses that predict the same outcome for all experiments?
    
   Here "beauty" does come into play. This is why special relativity is taught rather than Lorentz ether theory, even though the two are indistinguishable in terms of predicted outcomes.
    
    
    
   
6. Are you talking about something else entirely?

 

I like how you broke this down. Among those you listed, #5 is the closest, but maybe I should pick #6.

 

Let's see if Newton's First Law will serve as a better example. Though stated somewhat colloquially, this law says that a body at rest will remain at rest or a body in motion will maintain uniform motion unless acted upon by an external force.

 

Is there an opposing theory for this? Not that I am aware of. I do not know of a theory that says a body at rest will suddenly spring into motion even though no external force has been applied. So, is this a law for which no opposition can be formulated?

 

It has been suggested (by Poincarre, I believe) that Newton's first law is not a law. Rather, it is a tautology (self-evident merely due to the way it is defined). Should we see a body at rest begin to move, we would never presume that the 1st law has been violated. We would presume a force has been applied to the body - even if we cannot explain that force at the moment. If we can't explain it, we will devise an experiment to quantify it.

 

So, is there anything that would ever falsify our belief in the 1st law? Or, do we merely append data to explain events within the context of the 1st law?

[CharonY]

(and I mean a reasonable opposing theory)

 

If you are merely talking about logic, I wonder what you mean with reasonable. Because this :

 

And, let me clarify one point. This is an issue of logic, not of empiricism. Whether John's sister exists (and what evidence we have for or against) is a whole other question. The question is whether assigning something a property entails that something else does not have the property.

 

Implies to me that it is not necessary to be reasonable, as e.g. the existence of John's sister appears to be irrelevant. But here:

 

Is there an opposing theory for this? Not that I am aware of. I do not know of a theory that says a body at rest will suddenly spring into motion even though no external force has been applied. So, is this a law for which no opposition can be formulated?

 

You apply reason. You can formulate the theory that bodies do not need external forces to be moved, it is just not reasonable.

[Mokele]

Are we wrong in viewing Newton's First Law as a scientific hypothesis? Couldn't it also be seen as a definition - that any movement produced must be a result of a force?

 

It's also testable in the sense that it predicts anything which moves objects will have the same character - whatever force will, so long as it is constant and the object is of constant mass, constantly accelerate the object. It's entirely possible to find some external influence which doesn't have this effect - perhaps something that's dependent upon the object's speed, or for which mass has no effect? After all, a hypothesis can still be considered falsifiable even if the falsification isn't by designed experiment but by potential future discovery (see paleontology for many examples).

 

Also, remember that you don't always *need* two opposing hypotheses for science - it could sometimes be as simple as "I suspect things work this way, but if the experiment shows something different, clearly I'm wrong." This is common in animal behavior, where there's just so many possibilities of what an animal *could* do (ranging from plausible to ridiculous) that you cannot enumerate or test them all, but rather simple test to see if your one prediction is right or wrong.

 

Mokele

[D H]

Are we wrong in viewing Newton's First Law as a scientific hypothesis? Couldn't it also be seen as a definition - that any movement produced must be a result of a force?

You're on the right track, but forces are the subject of Newton's second law, not the first. The first law talks about the behavior of a particle that is not subject to a force.

 

Newton's first two laws are in part definitional and in part axiomatic. The axioms of Newton's first two laws:

1. Space and time are something distinct in and of themselves.
   
2. There is an absolute time that "flows equably without regard to anything external." We can only measure relative time (duration) rather than absolute time.
   
3. There is an absolute space that "remains always similar and immovable." That this absolute space is Cartesian is, I think, implicit in Newton's concept. (Non-Euclidean geometries were not perceived as valid for more 100 years or so after Newton's time.) Just as we can only measure relative time, we can only measure relative time, we can only measure relative space (displacement) rather than absolute space. In three dimensions, the relative displacement from some arbitrary point is a relative reference frame.
   
4. There are things called forces that affect the motion of an object.
   
5. Objects are endowed with mass, an absolute location, absolute motion, and absolute momentum. The absolute momentum of a constant mass object is the product of its mass and absolute motion.
   
6. Newton's first law: The absolute momentum of an object that is not subject to any forces is constant.
   
7. It is possible to find a relative reference frame (herein called an inertial reference frame) and a relative time such that the relative momentum of an object that is not subject to any forces is constant.
   
8. Newton's second law: The time derivative of an object's absolute momentum is proportional to the net force acting on an object, with the constant of proportionality being the same for all objects.
   
9. Principle of superposition: The net force on an object is the vectorial sum of the individual forces acting on the object. (These are not Newton's words. Newton predates the concept of a vector by 200 years. Newton used geometric arguments.)

 

Note that the first law only talks about what happens in the absence of forces. It does not describe what a force is, or how a force, if present, affects the motion of an object. That one can find an inertial reference frame is axiomatic. However, the last axiom can also be seen as definitional of a relative inertial reference frame. Newton's second law, coupled with the superposition principle (which David Hestenes calls Newton's fourth law) can be viewed as defining what constitutes a force.

[Resha Caner]

Newton's first two laws are in part definitional and in part axiomatic ...

 

Moving from that instance, can a general statement be made? Could we say that in cases like Newton's 1st Law, where we would not formulate an opposing law, it is axiomatic rather than a law or theory?

[Mokele]

I thought "laws" had to be axiomatic, which is what distinguishes them from theories, even well-supported theories like evolution or the Big Bang?

[D H]

Although the distinction between scientific theory and scientific law is a bit fuzzy, it is generally the other way around, Mokele. Laws are very simple, empirical, and final statements. Theories are deeper and a bit more malleable than are laws.

 

An example is black body radiation.

 

In 1896 Wilhelm Wien developed an empirical rule to describe the high frequency spectrum of thermal radiation, Wein's Law for black body radiation:

 

[math]I(\nu,T)=\frac {2h\nu^3}{c^2}e^{-\,\frac {h\nu}{kT}}[/math]

 

A few years later, Max Planck noticed that a very simple correction to Wein's Law enables a match to the full spectrum of a black body radiator:

 

[math]I(\nu,T)=\frac {2h\nu^3}{c^2}\frac 1 {e^{\frac {h\nu}{kT}}-1}[/math]

 

This is Planck's law, still a completely empirical law at the time it was published. Note well: This is not the Wein-Planck Law. Scientific laws are final. Suppose instead that Wein had developed a theory behind his equation and Planck made a minor correction to that theory. The modified theory would be called the Wein-Planck theory.

 

The theory of black body radiation was not developed until several more years had passed. The theory explains why Planck's law is indeed correct.