Theory--the word.

[Mike Cl]

Question about the word 'theory'.  I have grown to appreciate in my short time on this board, the vast and deep scientific knowledge of the posters here.  So, if anybody can give me an answer in English, it's you guys.  As I see it a theory is something that has been proven; all theories are testable, even proven ones.  But just because something is a theory does not make it ironclad.  Since theories are testable, a theory can be changed by more accurate testing.  Is the above correct?

And an hypothesis is basically an educated guess that can be tested, but hasn't been tested yet.  Is that correct?

Thanks for any answers.

[PickelledEggs]

Google's definition is : A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation.

So in short, a theory is an explanation that can be tested with observable evidence.

[Hydra009]

What Pickelled Eggs said.  A scientific theory is a model used to explain a given set of facts.  Unlike the public use of the word, theories do not graduate into facts.  And to answer your question, yes, theories can be reformulated to a degree to fit new discoveries.  However, falsifiability is essential to a good scientific theory.  Precambrian rabbits is the go-to one for evolution.

A hypothesis is a tentative explanation for a phenomenon usually presented as an if-then statement.  For example, the hypothesis that a feather will fall at the same rate as a hammer in a vacuum to show that speed of descent is independent of mass.  Theories explain a much broader set of phenomena.  For example, the theory of evolution ties together a great many scientific fields:  paleontology, genetics, biology, systematics, etc.

[Solitary]

Good post Hydra! Hypothesis is an attempt at explaining experimental results, or some phenomena observed in nature. A theory is a set of scientific assumptions which are consistent and are supported by some evidence, but not fully proved. I might add that a theory is self correcting when new evidence doesn't coincide with the theory and it has to be changed. That doesn't necessarily mean the theory is wrong, just that it needs to be amended so the new evidence fits into the theory, if not, the theory has to be changed with a new theory. The reason evolution is considered a fact is because even other divisions of science have confirmed it is correct with no exceptions. It would be like saying the earth is ball shaped, and then finding out it is not quite correct, but you would still be correct to call it ball shape, unless you were a pedantic jerk. Solitary

[Mike Cl]

I appreciate your answers.  I guess I am right to be a little piqued by people saying--evolution is just a theory, for example.   Yeah, it is a theory, which means it has been proven.  What they really think they mean is that evolution (to them) is a hypothesis or a guess.  I seem to see that the word 'theory' is almost always misused in everyday media; it seems most think of it as a guess of some sort.   It really irritates me when some of the scientific community misuse the word.  When I was teaching, fellow teachers misusing it drove me up the wall.

[Hydra009]

Whoa there, guys.  Unless you're talking about geometry, logic, or alcohol, using the term proof is a bad idea.  Scientific theories are still subject to potential falsification.  Well-supported (or well-substantiated) is a far more accurate term than proved.

The reason evolution is considered a fact is because even other divisions of science have confirmed it is correct with no exceptions.

It's a slight misnomer to say that the theory of evolution is itself a fact.  Speciation is a fact.  Mutation is a fact.  Extinction is a fact.  Heritable variation is a fact.  Etc.  Put all the pieces together and you get evolution.  Scientific theories explain facts, but are not facts in and of themselves.  Even extremely well-supported theories like evolution are technically tentative as well as continually subject to new additions as new information is gleaned, as has especially been the case with the theory of evolution in recent history.

(Though, if you mean fact not it terms of absolute certainty, but provisionally true - confirmed to such a degree that you'd have to be out of your gourd to think otherwise, then yes, the theory of evolution is a fact.)

[Gawdzilla Sama]

Evolution is a fact. We just don't understand fully the laws that are at work there. We have a theory as to how they work, but with just ~150 years of study we're not there yet.

[Johan]

I think the easiest way to explain this is to remember that science never tells us what is true. Science can only ever tell us what isn't true. The truth is then assumed by what is left over after the false possibilities are ruled out. Therefore every bit of scientific knowledge that exists is always subject to change as new information is revealed.

[josephpalazzo]

Question about the word 'theory'.  I have grown to appreciate in my short time on this board, the vast and deep scientific knowledge of the posters here.  So, if anybody can give me an answer in English, it's you guys.  As I see it a theory is something that has been proven; all theories are testable, even proven ones.  But just because something is a theory does not make it ironclad.  Since theories are testable, a theory can be changed by more accurate testing.  Is the above correct?
And an hypothesis is basically an educated guess that can be tested, but hasn't been tested yet.  Is that correct?
Thanks for any answers.

The best way to explain this is through an example.

Take the observation that all objects, irrespective of their size, shape or composition, fall at a constant rate in free fall. That rate is called the acceleration due to gravity, g. This fact requires an explanation. The theory that does that is Newton's theory of gravity, which states that any two objects attract each other with a force proportional to the masses and inversely with the distance squared. If the theory is good, it should be able to explain many facts, in this case, one can use Newton's equation to figure out the orbits of different planets, the time of low/high tides, the different phases of the moon, etc.

Is a theory final, or can it be changed? Well in this case, it was changed, even though there was an overwhelming body of facts supporting it. Newton's theory could not account for the recession of Mercury's perhilion. it could not account for photons being slowed down by gravity, and it could not account for time dilation in Einstein's theory of Special Relativity. Newton's theory was replaced by Einstein's theory of General Relativity. Note that GR contains all the features of Newtonian theory.  Can GR be replaced? Maybe, since it cannot account for gravity acting at Planck scales and would require to be quantized - an undertaking no one has accomplished so far.

[Solitary]

Whoa there, guys.  Unless you're talking about geometry, logic, or alcohol, using the term proof is a bad idea.  Scientific theories are still subject to potential falsification.  Well-supported (or well-substantiated) is a far more accurate term than proved.
It's a slight misnomer to say that the theory of evolution is itself a fact.  Speciation is a fact.  Mutation is a fact.  Extinction is a fact.  Heritable variation is a fact.  Etc.  Put all the pieces together and you get evolution.  Scientific theories explain facts, but are not facts in and of themselves.  Even extremely well-supported theories like evolution are technically tentative as well as continually subject to new additions as new information is gleaned, as has especially been the case with the theory of evolution in recent history.

(Though, if you mean fact not it terms of absolute certainty, but provisionally true - confirmed to such a degree that you'd have to be out of your gourd to think otherwise, then yes, the theory of evolution is a fact.)

That is exactally what I meant. It is considered a fact because of overwhelming evidence, even though it is still provisional, as all good science is. We know the earth is not flat is a fact from evidence.

[AllPurposeAtheist]

Theory: Any rightwing nutjob conspiracy uncovered about Obama.