You say

I say

Where is the problem, exactly?

How can I tell whether a theory is falsifiable?

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"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

OK, perhaps I could have worded it better, but I would probably still be writing the darned thing now...

Add me in there for sure. Probably Mill too... How does the second sentence not contradict the first? Paraphrase:

-testable means falsifiable if the tests are refutable
-if the tests are not refutable, they are not tests.

Ok... so then in order to describe something as a "test" it has to be falsifiable. Therefore all tests are falsifiable!

(for others - yes, I know there is an issue with using "test" and "prediction" as synonyms. I'm letting that go for now).

Ok, how about this: all good tests are refutable.
Ditto for me.

Soup, you keep saying those words aren't synonyms, but it appears to me that the way you use them, you are using them as synonyms.

russ_watters. This is the first time you have mentioned the isssue, and it is unlike you NOT to be pedantic, so the only conclusion I can possibly draw is that you have jumped on the bandwagon.

This is gibberish, at best misrepresentative; not paraphrasing.

Your last attempt said that 'Falsifiable = Falsified', thus suggesting that all scientific theories have been falsified. Need I say anymore?

I missed this one before: Now you're putting words in my mouth that I didn't say. What I said was: Not: 'falsifiable=falsified'

but: 'falsifiable=can be falsified' and therefore:
'can be falsified=falsifiable'

The word "falsifiable" and the phrase "can be falsified" are synonyms and can be used interchangeably.

P.S. You're getting abusive again.

Indeed.

What else can this mean?

Worzel picked you up on it here?

One more crack: If a theory has been falsified, then it must have been capable of being falsified, and it is(was) therefore falsifiable.

??? The very next sentence contains the explanation: I don't see how this is that hard, but let me break it down for you:

a = falsifiable
b = can be falsified

a=b and b=a

edit: I'm not quite sure what Worzel, was saying. => means "therefore" and is different than = equals. Worzel did say quite explicitly there that s/he thinks you're using the word incorrectly. In any case, if s/he interpreted my statement the same way you did, s/he was also incorrect.

I think we passed that one a while back. I need beer. Catch you later.

I think we all do. Phew!

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"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

How's this? A theory or concept that is falsifiable is capable of being verifiable, even if at first poorly understood. If we are not sure what is causing an observed effect in deep space, we are at least observing the effect itself so testable explanations based on applied physics could describe aspects of the observed phenomenon. This is one way how a theory can be built up. It is not a matter of faith, as the theories could be falsifiable, and subject to verification.

On the other hand, my theory is: If "A" (hot day) then "B" (cold beer).

OK, Soup, what exactly about DM/DE do you find unfalsifiable?

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

And that's really the whole point of this, isn't it? Thanks for getting it back on track.

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Help! Marxist literary critics are following me!

Ok I am back from working out of town and what do I find? More replies to this thread occured after I left than before I went away.

I have not had time to read all the pages but I have read soupd's long anticipated post.

Pains me to say it since I was so snarky before but I agree with soupdragon.

DM/DE is not a theory, it is a patch. It did not come about in order to make predictions it came about to match observations that did not fit the accepted rules. There is precious little about what dark matter & energy are that explains how it comes about in this universe.

It is not unlike (and members are gonna love this ) a scientific equivalent to UFO's.

UFO are unexplained phenomena and theories abound to explain them. I need not go into the theories but many of them would indeed fit as an explaination of the phenomena. These "theories are simply not testable and therefore not falsifiable.

In the case of D E & M we use the word "dark" in exactly the same way as Unidentified is used in UFO. There is an unidentified phenomena that can be observed and dark energy and matter are used to fit that phenomena just as alien supercraft are used to explain lights in the sky.

We have;
a) gravity works this way
b) the universe is not observed to obey the way gravity works
conclusion: there is unobserved dark matter in the universe.

But although it is being widely accepted as a proper conclusion it does not actually follow from a & b anymore, and is no more falsifiable, than;

a) there are other civilisations in the universe
b ) there are lights in the sky on earth
conclusion: the lights are the result of alien visitation.

Yes the first case is the result of precise measurements using all manner of hi-tech devices but DM/DE is not more directly observeable than the little green men ( of course the present vogue is for them to be grey) or the planet and civilisation of their origin. Both are inferred even if the former is an educated guess.

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"Man has always found it easier to sacrifice his life than learn the multiplication table." - Somerset Maugham

No problem, I have been trying to chime in here for awhile but it seems just about the time I had something to say someone else had already said it, and better then I could, just glad I could participate again lol.

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

Jaydeehess, What is gravity then?

We cant observe what causes the effects but we can observe the effects. Maybe this is a stupid question but, to me what you said works for gravity as well. atleast in the portion of we cant observe the cause of gravity only its effects. I would also like to ask, how does this make dm/de unfalsifiable or unscienitific?

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

If i could also mention that in your two examples, in the first we have a reasons to agree that gravity exists for lack of a better word throughout the universe and that we can predict its nature, in the second example we have no reason to agree one way or the other that there are aliens out there or that we could predict their nature.

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

We do know that gravity exists. We assume it as a law, a given. We don't know what it is. It can be measured in the laboratory. We can do work, tests, with it's effects. The same cannot be said of DM or DE. Our understanding of gravity is what drives the reasoning for DM. Saying that our understanding of gravity is flawed is just as good an answer to the observations in the universe as DM is. We simply don't throw out good laws without a fight and thus DM is inserted to maintain the laws of the effects of gravity. In fact the observations that do not fit the predictions of our accepted theory of the effect of gravity could be seen as a test to falsify that theory.

Newton deduced the Laws of Motion. They work fine on Earth. Einstein ammended the Laws of motion though. Was Newton wrong?

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"Man has always found it easier to sacrifice his life than learn the multiplication table." - Somerset Maugham

Basically, yes. But he was close.

Granted.

Would you say that Newton's laws were falsified then, and that Einstein went onto build a better theory, or that Einstein added auxiliary hypotheses?

But I said:
And then you say:
Which is pretty much the same thing.

Exactly, you were using SDs Falsifiable => Can be falsified to (a=>b) to say b=>a. While I agree with you that "can be falsified" means the same as "falsifiable" it doesn't follow simply by accepting that "falsifiable" implies "can be falsified".

Anyway, we all agree then that:

Falsifiable implies a theory can be falsified.
If a theory can be falsified it can make predictions that can be falsified.

Most of us think that:

1. If a prediction can be falsified then the thoery can be falsified.
2. If a theory can be falisified then the theory is falsifiable.

I'm still not sure which of 1 and 2 SD disagrees with.

ok, so dm isnt a theory by itself? Could it be considered maybe a sub theory, or something like that, of a bigger theory maybe? If so, what makes it unfalsifiable or unscientific?

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

I'd call DM a hypothesis.

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"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

Ok, that make sense UT. ty

As a hypothesis though does falsifiability still apply? and if so, Then, ill ask this of soupdragon2 since it is his claim that DM is unscientific, what about DM is unscientific?

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They call 'em fingers, but i've never seen em fing..... oh there they go!! otto

Was it that painful?

Yeah, I think we've got over all of this now.

1. Falsifiable implies that a theory can be falsified.
2. If a theory can be falsified it follows that it is falsifiable.

I have reservations about 2, but don't think they're strictly relevant, so I'll try and cut down on the pedantry for now.

Well, a hypothesis can be right or wrong. I guess that means it can be falsified.

Theory: Gravity
Problem: There seems to be too much.
Hypothesis: There's extra mass that we can't yet see.

Theory: Gravity
Problem: There seems to be too much.
Hypothesis: We don't yet understand gravity at the galactic scale.

Both hypotheses could be right, or neither, or just one. And either of them could be shown to be wrong. More importantly, either of them could be shown to be right. It just takes evidence.

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"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

1. We are now talking about theories and hypotheses. The difference being that a theory has been subjected to more testing.

2. They should both be falsifiable.

I think we will probably all agree on the above?
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3. If we discover problems with a theory, it can be rescued by adding an Auxiliary Hypothesis, on the strict condition that the AH makes the theory more falsifiable.

Is everbody happy with this? It is a strict criterion of Popper's Falsificationism!
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I contend that DM and DE fail the all important criteria of AHs on the basis that they make the original theories less falsifiable; they add subjectivity.
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My central argument above has vulnerabilities.

Some might argue that DM and DE are theories in their own right?
Some might not accept Popper's criterion?
It might even be argued that DM and DE increase the Fal of the theories?

I will be interested to see their arguments in this respect.

I'm going to assume that by "more falsifiable" you mean "more easily falsifiable," other wise I'm not sure what you're talking about.

The only problem I see with DM and DE is that "abscence of evidence is not evidence of abscence." There are people who will likely spend their entire lives searching for the stuff, even if it's never found. At that point it becomes "We understand gravity perfectly. The Dark Matter is messing up our calculations. We must find the Dark Matter!" for all eternity. However, one could just as easily turn away and say "We've been looking for this stuff for 80 years, and all we see is the same, original, gravitational evidence for it. The trail's gone cold at a dead end street. Time to move on." In one point of view, DM is infallible. In the other, it's torn r^-2 to shreds.

__________________
"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"