Notes and Thoughts on Imre Lakatos' 'Science and Pseudoscience'
My favourite quote:
"But the history of thought shows us that many people were committed to absurd beliefs. If the strength of beliefs were a hallmark of knowledge, we should have to rank some tales about demons, angels, devils, and of heaven and hell and knowledge. Scientist, on the other hand, are very skeptical of even their best theories."
Ok, lets get this out of the way right off the bat: I don't know if Imre Lakatos had an affinity for drinking milk.
The Demarkation Problem Revisited
Moving on to the demarkation problem and Lakatos' proposed solution. Here's the short version: A theory is scientific if it predicts novel facts and it's pseudo-scientific if its predictions are consistently refuted and it produces no new facts about the world. To see how he arrives at this position lets first look at his arguments against the competing demarkation theories including Popper's falsificationism and Kuhn's idea that science is marked by incorporating puzzle solving. Kuhn's demarkation line was drawn between enterprises that embrace unsuccessful predictions as research puzzles to be solved (sciences) and those that resort to hand waving to explain away unsuccessful predictions and do not incorporate the problems as part of their research (pseudoscience).
Vs. It's Science Because It's Derived from the Facts
The first argument is directed at the popular notion that what makes a theory scientific is that it is derived from the facts. But what exactly does it mean for a scientific theory to be supported by the facts? That Newton was doing science is pretty much indisputable, but did Newton derive his theory of motion from the facts? Newton claimed that he had deduced his theories from the facts of planetary motion which had been observed by Kepler. Kepler's observations were that the planets' orbits were elliptical but according to Newton's theory, planets would only follow such a path if they didn't disturb each other, which they do. Doh! So much for the facts. So, Newton devised a perturbation theory which holds that no planet moves in an ellipse.
The idea here is that facts are facts and theories are theories. Got it? A theory is an interpretation of facts, a story linking events together, if you will. There can be many different interpretations of the same set of facts, all of them conforming to the facts, no matter how wacky the the theory. There is also this idea that no theory takes into account every fact. It not uncommon to gloss over particular facts and/or outliers (events that don't conform with what we'd expect) which may be problematic for the theory.
Vs. Popper's Falsificationism (see: 'Thaaaat's Not Science: Part 1')
The prollem with falsificationism (for a full list see part 1) is that scientists don't throw away theories the moment a fact contracts it or doesn't conform to a prediction. Scientist will cling to theories for a long time before they are discarded. Disconfirming evidence is called an anomaly. Sometimes it's ignored for statistical reasons, sometimes the theory is modified to capture it. The point is, rarely is the whole theory thrown out for the sake of mere disconfirming evidence.
If scientists, like their pseudoscientist counterparts, don't reject theories based on non-conforming evidence, what makes one theory science and another pseudoscience?
Lakatos' Solution to the Demarkation Problem
Step one. We can have lots of fun. And by fun I mean, instead of considering individual hypotheses and theories to be the basic unit of scientific achievement, we should consider the unit to be "a research programme". Fun right? Science isn't simply a matter of trial and error, this would be trivial. A research programme is something that encompasses several interconnected theories and hypotheses.
Consider Newtonian physics. It is more that its four laws. These four laws form the core of the Newtonian program but are "protected from refutation by a vast 'protective belt' of auxiliary hypotheses". On top of all this, a programme has a problem solving method which includes mathematical and statistical techniques to interpret evidence and anomalies. If a planet doesn't move according to what the theory predicts, the scientist can check his hypotheses concerning atmospheric refraction, propagation of light in magnetic storms, and hundreds of other things that are all contained within the programme.
Newton's theory of physics, Einstein's relativity theory, quantum mechanics, evolutionary biology, homoeopathy, "The Secret", and alchemy are all research programmes that have a core and protective belt of elaborate problem-solving machinery. At every stage in their development there is disconfirming evidence, anomalies; there are problems. But how do we separate the scientific programmes from the pseudoscientific?
Step 2, I'll explain it to you. Scientific programmes are all able to predict novel facts, "facts which had been either undreamt of, or have indeed been contradicted by previous rival programmes." What are some examples of novel facts? Einsteinian relativity predicted that the path of light will be altered by objects with large mass. That's why light seems to bend when I flex my biceptors. I kid! I kid! Einstein's prediction was verified during a solar eclipse. If you're curious about the details, click on these pre-googled links:
http://en.wikipedia.org/wiki/Tests_of_general_relativity
http://www.youtube.com/watch?v=IVHQH4UPIFs
Another example is Halley's prediction, within the Newtonian programme, that the comet that bares his name (co-incidence or what?!) would return in 72 years. He died before it did, but his prediction didn't! Before Halley, er'body thought comets only travelled in straight lines but from within the Newtonian programme he was able to shew that some move in hyperbolas or parabolas, and others in ellipses.
So, what separates pseudo-scientific programmes from the scientific? The scientific programmes make predict previously unknown facts; they lead to further discovery; discovery that competing theories could not make. In a word, they are progressive.
Pseudo-science, on the other hand, is degenerative. Theories are retrofitted and modified only to accomodate existing facts. Has homoeopathy predicted any novel facts about the world? How about the programme of The Law of Stupidity, oops, Attraction? Nope. What people who work within these programmes do is reinterpret existing facts in such a way so that they will conform with their pre-existing model. Nothing novel about the world ever emerges.
"What really count are dramatic, unexpected, stunning predictions; a few of them are enough to tilt the balance; where theory lags behind facts, we are dealing with miserable degenerating research programmes."
Showing posts with label Falsificationism. Show all posts
Showing posts with label Falsificationism. Show all posts
Saturday, January 28, 2012
Tuesday, January 24, 2012
Thaaat's Not Science!
The Demarkation Problem: Notes and Discussion of Karl Popper's Falsificationism
Overview
One issue in the philosophy of science is known as the demarkation problem. That is, where do we draw the line between genuine science and pseudo-science? What's the difference between astronomy and astrology? Chemistry and alchemy? Medicine and homeopathy? Psychology and Freudian psycho-analysis? Evolutionary biology and creation "science"? Why is the study of literature, history, or philosophy not considered a science? Are the social sciences, science? All these questions are relevant to the demarkation problem.
Possible Answers
The obvious answer is that something is science if the person doing/discovering it is wearing a lab coat, works with test tubes, beakers, and Bunsen burners. But as appealing as this solution is to our intuitions we cannot ignore the fact that alchemists also wear lab coats, use many beakers and test tubes (filled with many colourful liquids, no less!) AND use several Bunsen burners all at the same time--and lets not forget that they measure their contents at the meniscus! They even use cool spiral shaped glass tubes that connect to other beakers. Alas, we might need to look elsewhere to solve our demarkation problem.
One other possible answer is to say that something is science if and only if it true. This won't work for several reasons: (1) Every true state statement will be considered scientific. Consider the statement "All unmarried men are bachelors". Under our definition of science, by making this statement we are "doing science" and making a scientific statement. (2) This would make things like Newtonian physics and Darwin's account of evolution not science. Even though Newtonian physics isn't perfect and was superseded by Einsteinian physics, it's still used in science and when scientists use it, they are still doing science. Darwin theory of evolution pre-dated the discovery of DNA so while his specific account of evolution was incorrect, it doesn't seem correct to say he wasn't doing science. Lets try a different criterion.
How about "science uses the empirical method"? But so do many pseudo-sciences like astrology. Also, if we restrict science to areas that use the empirical method we must exclude things like theoretical physics. Hmmm...
Lets try this: if there is a "preponderance of evidence" for a theory then it's science. The immediate problem is that early scientific inquiry into a problem won't be considered science until a lot of evidence has accumulated. Do we want to say that when a scientist (in a lab coat, using beakers and Bunsen burners) makes a new discovery, they aren't doing science no matter how sound their method? This doesn't seem right. The other problem, which occurs very often in pseudo-science, is that theories can be interpreted to accept any data set.
Here are a few quick examples: (1) In para-psychology anytime a skeptic tries to observe or replicate the results, the subsequent absence of the effect is explained away by saying the presence of the non-believer annihilates the para-psychological effects. This only further confirms their (now modified) theory, that para-psychological effects don't work around skeptics. (2) Consider astrology: predictions are so general that they can be made to retroactively apply to at least one event that happens throughout the day, further confirming the theory; i.e., adding evidence. (3) Consider something like the pop-psychological belief that "the universe always conspires to help you". It is easy to see how proponents can always retrofit events and interpretations to make it true. Take two opposite situations: you lose your key and you don't lose your keys. Under the theory, proponents can always apply retrospective reasons for why one or the other happened (use your imagination). That is, both A and ~A make the theory true. But any theory that contains a statement and it's contradiction is inconsistent. In short--it's nonsense. But either way, the theory is confirmed.
To summarize, just because we can find verifications for a theory does not allow us to say we are doing science or that the theory is scientific. Here's a good illustration of the problem with using verification (or "preponderance of evidence") to gauge whether something is science.
http://www.youtube.com/watch?v=WB-qSXSsoUI
Popper's Falsificationism
So, what do? How ought we to distinguish science from pseudo-science? Listen up peoples cuz my main man Karl Popper's about to drop some knowledge on your ass, then we is going to discuss it. Karl Popper was one the first contemporary philosophers to rassle with this problem and he came up with a 7 point list to distinguish the science from the pseudo-science. They can be summed up as follows: "the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability".
Vas does this mean? Lets break this shit down in to terms I understand. I know that testability prolly has something to do with test tubes, but what about those other big words? Popper is saying that to test whether a theory is scientific you have to test it in such a way that failure is possible. In a more concrete form you will do something like this: make a specific "risky" prediction about something your theory entails. For example, if we want to test a theory of gravity we can say "this theory predicts that object z will fall distance y, in time x". With this sort of specific testable statement there is a real chance that the theory could fail. Or is there? Ah! ha!
It seems we have prollem. Popper's falsificationism is certainly a good first step but there are some difficulties. How many specific "risky" tests do we have to make before we can accept a theory as scientific? Consider Newton's law of gravity which has been around since the 17th Century. Presumably it had been rigorously tested many times with specific testable predictions since it's introduction to the scientific cannon. When Einsteinian gravity was shown to be a better theory did we say that all pre-Einsteinian scientists had been doing pseudo-science? Nope. Here's the prollem. There are infinitely many tests we can do on a theory, only our imagination is the limit. Einstein had a greater imagination than all physicists prior to him, so he was able to falsify the Newtonian theory. Who's to say that one day some hyper-imaginative person comes up with a test that falsifies Einstein's theory? Or any of our other scientific theories, for that matter? How many tests make a theory scientific?
Another question is why do we consider Newtonian physics to be science, even now that it has been falsified? If theories can be falsified, yet still be considered science, on what grounds can we exclude known pseudo-science? And related to this is why do we say that past scientists who worked off of later disproven models were doing science?
It seems that the ability for a theory to be falsified is a start to uncovering the demarkation line, but is not nearly enough.
Overview
One issue in the philosophy of science is known as the demarkation problem. That is, where do we draw the line between genuine science and pseudo-science? What's the difference between astronomy and astrology? Chemistry and alchemy? Medicine and homeopathy? Psychology and Freudian psycho-analysis? Evolutionary biology and creation "science"? Why is the study of literature, history, or philosophy not considered a science? Are the social sciences, science? All these questions are relevant to the demarkation problem.
Possible Answers
The obvious answer is that something is science if the person doing/discovering it is wearing a lab coat, works with test tubes, beakers, and Bunsen burners. But as appealing as this solution is to our intuitions we cannot ignore the fact that alchemists also wear lab coats, use many beakers and test tubes (filled with many colourful liquids, no less!) AND use several Bunsen burners all at the same time--and lets not forget that they measure their contents at the meniscus! They even use cool spiral shaped glass tubes that connect to other beakers. Alas, we might need to look elsewhere to solve our demarkation problem.
One other possible answer is to say that something is science if and only if it true. This won't work for several reasons: (1) Every true state statement will be considered scientific. Consider the statement "All unmarried men are bachelors". Under our definition of science, by making this statement we are "doing science" and making a scientific statement. (2) This would make things like Newtonian physics and Darwin's account of evolution not science. Even though Newtonian physics isn't perfect and was superseded by Einsteinian physics, it's still used in science and when scientists use it, they are still doing science. Darwin theory of evolution pre-dated the discovery of DNA so while his specific account of evolution was incorrect, it doesn't seem correct to say he wasn't doing science. Lets try a different criterion.
How about "science uses the empirical method"? But so do many pseudo-sciences like astrology. Also, if we restrict science to areas that use the empirical method we must exclude things like theoretical physics. Hmmm...
Lets try this: if there is a "preponderance of evidence" for a theory then it's science. The immediate problem is that early scientific inquiry into a problem won't be considered science until a lot of evidence has accumulated. Do we want to say that when a scientist (in a lab coat, using beakers and Bunsen burners) makes a new discovery, they aren't doing science no matter how sound their method? This doesn't seem right. The other problem, which occurs very often in pseudo-science, is that theories can be interpreted to accept any data set.
Here are a few quick examples: (1) In para-psychology anytime a skeptic tries to observe or replicate the results, the subsequent absence of the effect is explained away by saying the presence of the non-believer annihilates the para-psychological effects. This only further confirms their (now modified) theory, that para-psychological effects don't work around skeptics. (2) Consider astrology: predictions are so general that they can be made to retroactively apply to at least one event that happens throughout the day, further confirming the theory; i.e., adding evidence. (3) Consider something like the pop-psychological belief that "the universe always conspires to help you". It is easy to see how proponents can always retrofit events and interpretations to make it true. Take two opposite situations: you lose your key and you don't lose your keys. Under the theory, proponents can always apply retrospective reasons for why one or the other happened (use your imagination). That is, both A and ~A make the theory true. But any theory that contains a statement and it's contradiction is inconsistent. In short--it's nonsense. But either way, the theory is confirmed.
To summarize, just because we can find verifications for a theory does not allow us to say we are doing science or that the theory is scientific. Here's a good illustration of the problem with using verification (or "preponderance of evidence") to gauge whether something is science.
http://www.youtube.com/watch?v=WB-qSXSsoUI
Popper's Falsificationism
So, what do? How ought we to distinguish science from pseudo-science? Listen up peoples cuz my main man Karl Popper's about to drop some knowledge on your ass, then we is going to discuss it. Karl Popper was one the first contemporary philosophers to rassle with this problem and he came up with a 7 point list to distinguish the science from the pseudo-science. They can be summed up as follows: "the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability".
Vas does this mean? Lets break this shit down in to terms I understand. I know that testability prolly has something to do with test tubes, but what about those other big words? Popper is saying that to test whether a theory is scientific you have to test it in such a way that failure is possible. In a more concrete form you will do something like this: make a specific "risky" prediction about something your theory entails. For example, if we want to test a theory of gravity we can say "this theory predicts that object z will fall distance y, in time x". With this sort of specific testable statement there is a real chance that the theory could fail. Or is there? Ah! ha!
It seems we have prollem. Popper's falsificationism is certainly a good first step but there are some difficulties. How many specific "risky" tests do we have to make before we can accept a theory as scientific? Consider Newton's law of gravity which has been around since the 17th Century. Presumably it had been rigorously tested many times with specific testable predictions since it's introduction to the scientific cannon. When Einsteinian gravity was shown to be a better theory did we say that all pre-Einsteinian scientists had been doing pseudo-science? Nope. Here's the prollem. There are infinitely many tests we can do on a theory, only our imagination is the limit. Einstein had a greater imagination than all physicists prior to him, so he was able to falsify the Newtonian theory. Who's to say that one day some hyper-imaginative person comes up with a test that falsifies Einstein's theory? Or any of our other scientific theories, for that matter? How many tests make a theory scientific?
Another question is why do we consider Newtonian physics to be science, even now that it has been falsified? If theories can be falsified, yet still be considered science, on what grounds can we exclude known pseudo-science? And related to this is why do we say that past scientists who worked off of later disproven models were doing science?
It seems that the ability for a theory to be falsified is a start to uncovering the demarkation line, but is not nearly enough.
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