The problem is that "theory" has always meant something different in science and now it means more than one thing.
Early scientists noted many regularities in the natural world. In particular, changes in one quantity were seen to be dependent on changes in other quantities in ways that could be described using algebra or, more often, calculus. Let's just say "maths".
The resulting mathematical expressions were initially called "Laws". This was partly influenced by mechanistic views of nature. Lawful behaviour appears to be mechanistic.
Scientific explanations are ideally causal. For example we might state a regularity like F=ma (where a is the second derivative of position x). And we might understand this to say that a net external force causes a mass to accelerate. Although philosophers have a lot of say about this kind of language.
The combination of a mathematical law and a causal explanation came to be called a scientific theory.
Ideally, and historically until the 20th century, a mathematical law should follow observation. It's not the case, historically, that one proposes a theory and then seeks to prove it. Rather, following Galileo, we observe something new and we try to explain it in terms of existing mathematical laws and causal explanations. If that fails, the scientist then proposes a new theory. For example, Galileo observed four "stars" in orbit around the planet Jupiter, which could not be explained in terms of the prevailing worldview (a melange of Aristotle, Ptolemy, and Augustine). And eventually that worldview collapsed as a result.
But it is tricky. None of the examples you cite appears to me to be a scientific theory. If I work through them, perhaps you will see why.
For example "dark matter" is not a scientific theory. Dark matter is a place holder for an eventual theory that will explain the rotational speeds of galaxies. Because when we tote up all the visible matter, and we apply the relevant mathematical laws and explanations, we cannot explain the way we observe galaxies rotating. The causality doesn't work.
In this case, we have observations that disagree with established theory (i.e. general relativity). The observations have been repeatedly confirmed and thus we take them to reflect reality, and to expose a weakness in the theory. But we don't yet have a replacement.
String Theory is an entirely different beast, but also not a scientific theory. Scientists believe that gravity should be quantised and have been searching for decades for a way to do that (I see this belief as foolish and unscientific, but no one listens to me). String theory is a failed attempt to reconcile relativity theory and quantum theory. In the final analysis, string theory doesn't seem to say anything at all about the natural world: it has produced no new mathematical laws or causal explanations. And thus it has no claim to either describe or explain the natural world, which is the whole point of science.
String theory reflects a major theme in modern physics, which is the speculative manipulation of existing mathematics in an attempt to create a new mathematical law that makes a new prediction. Then physicists go looking for evidence that the prediction is accurate and precise. This whole methodology of manipulating mathematics looked promising since it gave birth to quantum mechanics. But since then it has largely failed to produce any meaningful results. And even QM only predicts probabilities, not actualities. Which in turn means that quantum mechanics cannot provide causal explanations. Physicists keep trying to predicting new particles in this way, and then fail to find any evidence of them.
Gravity is not a theory either. Gravity is the name of a phenomena which is universally observed by human beings regardless of culture. Newtons Law of gravitation outlined the way that various quantities change with respect to each other, but Newton provided no causal explanation. It was Laplace who came up with the explanation in the form of the gravitational field.
Relativity is a scientific theory. It both describes how quantities change in relation to each other using maths and it offers a causal explanation of the relations. In layman's terms: matter causes space to bend, and (bent) space causes matter to move in curves.
But scientists never set out to prove relativity. That's not really how it works. Rather we use the maths to make predictions, then we test to see how accurate and precise the prediction is. In doing so we try to eliminate other causes, to see if the causal explanation works. Relativity is extremely accurate and precise, except at the big bang, where is becomes inaccurate. And it's causal explanation explains everything except the big bang.
Relativity is probably the best scientific theory we have. But we have never "proved" it in the sense you mean. We have merely demonstrated that it provides a highly reliable, highly accurate and precise guide to how things move in relation to (or relative to) each other. And a causal explanation of why it happens as it does.
It's a complex topic and difficult to convey all that is needed in an off the cuff answer. I wish I knew a useful resource to point you towards, but I'm relying on a lifetime of accumulated knowledge rather than specific sources.
The general definition of "Theory" isn't the scientific definition. Many words have different meanings in different disciplines.
I've always tried to differentiate between "theory" and "hypothesis". Theory is testable (relativity for example has many experiments behind it, with no failures). Hypothesis is our best guess given the data we have. Thus, dark matter/energy or string theory are based on observation but haven't been deeply tested yet.
Unfortunately, I'm probably in the minority when it comes to these words.
Keep in mind scientists are human too. They don't want to spend decades of their life looking into "string hypothesis", thus they call it a theory to validate their work.
We don’t yet have a theory of dark matter or energy. Dark matter and dark energy are names for observations that we don’t yet have theories for. We do have a well working model of how they behave. But we have many competing hypotheses about what they are and how they come about. One of them might become the accepted theory at some point. For that, it would need to make reliable, novel, testable predictions that can be confirmed, and be able to make connections that the others can’t. At that point, we still haven’t proven that it’s absolutely correct, but it will be the best description and explanation we currently have.
We actually also don’t have a theory of strings. We have many competing string theories, but those are theories in the mathematical sense - mathematical models that are internally consistent. They aren’t yet scientific theories, because we can’t test them, yet, to be able to distinguish between which one best conforms to reality. Basically what string scientists are working on is trying to make unique predictions using their preferred model, that when tested using novel experiments, would disprove either their own model or the other models. We will do that until there is only one model left that we cannot prove wrong, and at that point it will become the accepted scientific theory. (This is a bit oversimplified, other aspects like how “useful” the theory is also play a role. )
Theories in science aren't necessarily ‘proven’, that's a bit of a loaded term. Theories are accepted or not accepted.
When talking about things like unobservable posits (dark matter etc) you accept them, or not, based on the reasons given, and how convincing the evidence is.
To demand proof, in a mathematical sense, or an ordinary language sense, or a formal sense, before accepting a theory as ‘proven’ would be demanding an epistemic grounding that may not exist. We have to start somewhere, to build up to an acceptance based on evidence, and that often involves brute facts that are almost axiomatic. Otherwise we’d get nothing done and our theories would be stuck at the level of abstraction.
You may be misunderstanding the word theory as used in everyday life VS in science. A theory in science means a structured explanation from evidence, logic, and testing. If it gains enough popularity, people then try to attack it to disprove it. If a theory keeps surviving this, confidence in it grows.
Theories come about because scientists make them up. To be sure, a good theory will be inspired by experiments, observed regularities, and already existing scientific theories. But there just isn't anything about a theory that requires the theory to be provable in order for the theory to come about. They are made up.
Which of my claims are you disputing? Do scientists not make up theories? Are good theories not inspired by experiments, observed regularities, and other scientific theories?
They don’t make up theories. You could say they “make up” hypotheses. Only when a hypothesis is supported by evidence, for example through experiments and observations, can it propagate to became a scientific theory.
I don't know what to say, other than that I disagree. A theory is a product of the scientist's thinking.
>Thus, it is evident that theories are imaginative constructions of the human mind—the results of philosophical and aesthetic judgments as well as of observation—for they are only suggested by observational information rather than inductively generalized from it.
- Britannica Editors. "scientific theory". Encyclopedia Britannica
No, a theory is the product of many scientists thinking, testing, discussing, refining and coming to a consensus. No scientist worth their salt would ever say “you know, I just came up with this theory”.
You wrote earlier “a good theory will be inspired by experiments, observed regularities, and already existing scientific theories”, which is just wing. Any accepted scientific theory (not just a good one) will not just be inspired, but strongly supported by observation and experimentation. If it isn’t, it’s simply just a hypothesis. That’s my point.
The theory of X is just the collection of everything we reliably know about X.
The theory of gravity, for example, includes many different aspects, like Newton's laws of attraction, Keppler's laws of orbital mechanics and Einstein's laws of curving time-space.
Every single law in here could need changes to explain newer findings and measurements. Thus the theory always changes. But with every change it gets closer to describing the real thing.
Prajnamarga | 14 hours ago
The problem is that "theory" has always meant something different in science and now it means more than one thing.
Early scientists noted many regularities in the natural world. In particular, changes in one quantity were seen to be dependent on changes in other quantities in ways that could be described using algebra or, more often, calculus. Let's just say "maths".
The resulting mathematical expressions were initially called "Laws". This was partly influenced by mechanistic views of nature. Lawful behaviour appears to be mechanistic.
Scientific explanations are ideally causal. For example we might state a regularity like F=ma (where a is the second derivative of position x). And we might understand this to say that a net external force causes a mass to accelerate. Although philosophers have a lot of say about this kind of language.
The combination of a mathematical law and a causal explanation came to be called a scientific theory.
Ideally, and historically until the 20th century, a mathematical law should follow observation. It's not the case, historically, that one proposes a theory and then seeks to prove it. Rather, following Galileo, we observe something new and we try to explain it in terms of existing mathematical laws and causal explanations. If that fails, the scientist then proposes a new theory. For example, Galileo observed four "stars" in orbit around the planet Jupiter, which could not be explained in terms of the prevailing worldview (a melange of Aristotle, Ptolemy, and Augustine). And eventually that worldview collapsed as a result.
But it is tricky. None of the examples you cite appears to me to be a scientific theory. If I work through them, perhaps you will see why.
For example "dark matter" is not a scientific theory. Dark matter is a place holder for an eventual theory that will explain the rotational speeds of galaxies. Because when we tote up all the visible matter, and we apply the relevant mathematical laws and explanations, we cannot explain the way we observe galaxies rotating. The causality doesn't work.
In this case, we have observations that disagree with established theory (i.e. general relativity). The observations have been repeatedly confirmed and thus we take them to reflect reality, and to expose a weakness in the theory. But we don't yet have a replacement.
String Theory is an entirely different beast, but also not a scientific theory. Scientists believe that gravity should be quantised and have been searching for decades for a way to do that (I see this belief as foolish and unscientific, but no one listens to me). String theory is a failed attempt to reconcile relativity theory and quantum theory. In the final analysis, string theory doesn't seem to say anything at all about the natural world: it has produced no new mathematical laws or causal explanations. And thus it has no claim to either describe or explain the natural world, which is the whole point of science.
String theory reflects a major theme in modern physics, which is the speculative manipulation of existing mathematics in an attempt to create a new mathematical law that makes a new prediction. Then physicists go looking for evidence that the prediction is accurate and precise. This whole methodology of manipulating mathematics looked promising since it gave birth to quantum mechanics. But since then it has largely failed to produce any meaningful results. And even QM only predicts probabilities, not actualities. Which in turn means that quantum mechanics cannot provide causal explanations. Physicists keep trying to predicting new particles in this way, and then fail to find any evidence of them.
Gravity is not a theory either. Gravity is the name of a phenomena which is universally observed by human beings regardless of culture. Newtons Law of gravitation outlined the way that various quantities change with respect to each other, but Newton provided no causal explanation. It was Laplace who came up with the explanation in the form of the gravitational field.
Relativity is a scientific theory. It both describes how quantities change in relation to each other using maths and it offers a causal explanation of the relations. In layman's terms: matter causes space to bend, and (bent) space causes matter to move in curves.
But scientists never set out to prove relativity. That's not really how it works. Rather we use the maths to make predictions, then we test to see how accurate and precise the prediction is. In doing so we try to eliminate other causes, to see if the causal explanation works. Relativity is extremely accurate and precise, except at the big bang, where is becomes inaccurate. And it's causal explanation explains everything except the big bang.
Relativity is probably the best scientific theory we have. But we have never "proved" it in the sense you mean. We have merely demonstrated that it provides a highly reliable, highly accurate and precise guide to how things move in relation to (or relative to) each other. And a causal explanation of why it happens as it does.
It's a complex topic and difficult to convey all that is needed in an off the cuff answer. I wish I knew a useful resource to point you towards, but I'm relying on a lifetime of accumulated knowledge rather than specific sources.
kellyratio | 15 hours ago
Explanations for observations
For_Writing | 13 hours ago
The general definition of "Theory" isn't the scientific definition. Many words have different meanings in different disciplines.
I've always tried to differentiate between "theory" and "hypothesis". Theory is testable (relativity for example has many experiments behind it, with no failures). Hypothesis is our best guess given the data we have. Thus, dark matter/energy or string theory are based on observation but haven't been deeply tested yet.
Unfortunately, I'm probably in the minority when it comes to these words.
For_Writing | 13 hours ago
Keep in mind scientists are human too. They don't want to spend decades of their life looking into "string hypothesis", thus they call it a theory to validate their work.
ipreuss | 15 hours ago
We don’t yet have a theory of dark matter or energy. Dark matter and dark energy are names for observations that we don’t yet have theories for. We do have a well working model of how they behave. But we have many competing hypotheses about what they are and how they come about. One of them might become the accepted theory at some point. For that, it would need to make reliable, novel, testable predictions that can be confirmed, and be able to make connections that the others can’t. At that point, we still haven’t proven that it’s absolutely correct, but it will be the best description and explanation we currently have.
We actually also don’t have a theory of strings. We have many competing string theories, but those are theories in the mathematical sense - mathematical models that are internally consistent. They aren’t yet scientific theories, because we can’t test them, yet, to be able to distinguish between which one best conforms to reality. Basically what string scientists are working on is trying to make unique predictions using their preferred model, that when tested using novel experiments, would disprove either their own model or the other models. We will do that until there is only one model left that we cannot prove wrong, and at that point it will become the accepted scientific theory. (This is a bit oversimplified, other aspects like how “useful” the theory is also play a role. )
Meet-me-behind-bins | 14 hours ago
Theories in science aren't necessarily ‘proven’, that's a bit of a loaded term. Theories are accepted or not accepted.
When talking about things like unobservable posits (dark matter etc) you accept them, or not, based on the reasons given, and how convincing the evidence is.
To demand proof, in a mathematical sense, or an ordinary language sense, or a formal sense, before accepting a theory as ‘proven’ would be demanding an epistemic grounding that may not exist. We have to start somewhere, to build up to an acceptance based on evidence, and that often involves brute facts that are almost axiomatic. Otherwise we’d get nothing done and our theories would be stuck at the level of abstraction.
thunderfbolt | 16 hours ago
You may be misunderstanding the word theory as used in everyday life VS in science. A theory in science means a structured explanation from evidence, logic, and testing. If it gains enough popularity, people then try to attack it to disprove it. If a theory keeps surviving this, confidence in it grows.
AdeptnessSecure663 | 15 hours ago
Theories come about because scientists make them up. To be sure, a good theory will be inspired by experiments, observed regularities, and already existing scientific theories. But there just isn't anything about a theory that requires the theory to be provable in order for the theory to come about. They are made up.
ipreuss | 15 hours ago
You’re confusing hypothesis and theory. For a hypothesis to become accepted as a scientific theory, it needs to have lots of evidence behind it.
AdeptnessSecure663 | 13 hours ago
Which of my claims are you disputing? Do scientists not make up theories? Are good theories not inspired by experiments, observed regularities, and other scientific theories?
ipreuss | 11 hours ago
They don’t make up theories. You could say they “make up” hypotheses. Only when a hypothesis is supported by evidence, for example through experiments and observations, can it propagate to became a scientific theory.
AdeptnessSecure663 | 10 hours ago
I apologise, I think "make up" wasn't the right phrase. I should've said "scientists come up with theories".
ipreuss | 9 hours ago
But they don’t. They come up with hypotheses.
AdeptnessSecure663 | 9 hours ago
I don't know what to say, other than that I disagree. A theory is a product of the scientist's thinking.
>Thus, it is evident that theories are imaginative constructions of the human mind—the results of philosophical and aesthetic judgments as well as of observation—for they are only suggested by observational information rather than inductively generalized from it.
- Britannica Editors. "scientific theory". Encyclopedia Britannica
ipreuss | 6 hours ago
No, a theory is the product of many scientists thinking, testing, discussing, refining and coming to a consensus. No scientist worth their salt would ever say “you know, I just came up with this theory”.
You wrote earlier “a good theory will be inspired by experiments, observed regularities, and already existing scientific theories”, which is just wing. Any accepted scientific theory (not just a good one) will not just be inspired, but strongly supported by observation and experimentation. If it isn’t, it’s simply just a hypothesis. That’s my point.
Etainn | 14 hours ago
The theory of X is just the collection of everything we reliably know about X.
The theory of gravity, for example, includes many different aspects, like Newton's laws of attraction, Keppler's laws of orbital mechanics and Einstein's laws of curving time-space.
Every single law in here could need changes to explain newer findings and measurements. Thus the theory always changes. But with every change it gets closer to describing the real thing.
Theories cannot be disproven, only enhanced.