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by jibbirish 4884 days ago
This is the very core of our scientific method (critical rationalism, Karl Popper [1]), theoretical models can only be used in science when they can be falsified. That is why we call them hypothesis (from the Greek word for assumption [2]). Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive.

For example, we can observe a thousand white swans in the world, and hypothesize that all swans are white. That is until we encounter that one black swan, and our hypothesis has been falsified.

[1] http://en.wikipedia.org/wiki/Karl_Popper [2] http://en.wikipedia.org/wiki/Hypothesis

2 comments

No, the black swan is a figment of your imagination. It wasn't a swan. You didn't know what you were looking at. You made it up. I don't care that lots of people saw it, you're all delusional. You're crackpots.

The problem with the scientific method is that scientists become very attached to their hypotheses, and the longer a hypothesis stands the more attached scientists get. This causes them to reject contradictory evidence, often going to ridiculous lengths to do so. A change of the hypotheses, a scientific revolution, only happens on the fringes of science when a maverick persists in examining evidence that most scientists reject.

I would recommend reading "The Structure of Scientific Revolutions" by Thomas S. Kuhn.

Scientific revolutions are far more widespread and involve many more scientists than you may think. Even during the earliest stages of the Copernican revolution there were many scientists who ascribed to the ideals. You may only hear about Copernicus, Darwin, Maxwell, and a few other notable scientists but the revolutions included many many people. Some of these people may have irrationally stuck to their previous hypotheses at each of these transitions but that is GOOD. Skepticism in science is critical to its function. If the skepticism is not entirely misplaced or competing theories still have merit for exploration, it will not die out (It's more complicated than this, but for the most part holds true).

As for the climate change in reply to this posts' parent: go on scholar.google.com and find real peer reviewed papers on climate change or go find the high impact environmental journals and often cited papers. Then find the papers that cite those papers that contain actual data!

Scientists have gathered a massive amount of data on melting ice, carbon dioxide concentrations, and world wide pollution. The jury is still out on whether or not humans are a major contributor to carbon dioxide emissions but it is irrelevant when atmospheric CO2 concentrations and temperatures are increasing. This may simply be a natural cycle but it is wise to err on the side of caution until we know more about the equilibrium conditions of the system.

The more troubling problem is pollution and deforestation that reduces the number of oxygen producing organisms. Even after ice ages and mass extinction events, the most important organisms for oxygen production in our atmosphere have been phytoplankton, which currently account for probably about half of all of the oxygen produced by plants. Already there is evidence pollution is drastically reducing these populations [1][2]. If this is proven to be true, there is unlikely to be some other mechanism on Earth to replace the phytoplankton in oxygen production (unless we force the evolution of a phytoplankton species immune to industrial pollution...)

Edit: [1] http://www.nature.com/nature/journal/v466/n7306/full/nature0...

[2] http://www.nature.com/nature/journal/v444/n7120/full/nature0...

I apologize that these papers are behind a paywall, but no news article for the public can do them justice. When you jump into the data for both papers you see science in action: a complex web of variables and events that we are trying to understand.

Why is it so hard to build an efficient artificial solar powered CO2 + H20 -> O2 + carbohydrate machine?
The mechanisms for converting water and atmospheric CO2 into oxygen evolved over a billion+ years before the Earth's atmosphere even supported aerobic organisms on land with every variable crucial to the survival of producer organisms painfully optimized. I don't think we even have a good quantum mechanical description of chlorophyll and its electron transport chain, which might have ridiculously high efficiencies compared to our solar panels (I think I ready this somewhere?). Once you add the chemical pathways for taking the energy and storing it with CO2/H2O, you increase the complexity many orders of magnitude. Even if we can replicate the pathway, scaling it up to actually impact the CO2/O2 ratios would be both economically and technologically difficult.
it's hard to beat the cost/efficiency ratio of trees
Prime example: climate change.

We have precisely fuck all idea what is going on regardless of the models.

Proof of this can be found by examining all the climate change news articles based on scientific papers going back to the impending ice age in 1972 (people have a short memory for climatology theories).

"Proof of this can be found by examining all the climate change news articles based on scientific papers going back to the impending ice age in 1972 (people have a short memory for climatology theories)."

While it makes a good talking point, it was not the case.

http://www.skepticalscience.com/ice-age-predictions-in-1970s...

News articles can not be relied on to present science and the views of scientists accurately. Controversy is news, consensus is not. Very few publications care enough to get their science reporting right, and it's expensive to have people on staff who are capable of doing it.
Relevant Asimov's classic article: http://chem.tufts.edu/answersinscience/relativityofwrong.htm

YMMV.

Thank you, you explained better an beyond the usual repetition

There's so much of this it's not even funny. The last part of my post is in this gist.

But in physics this is easier to work around. In other areas not so much

Also, the scientific method and Popper's ideas are a philosophical construct. One has to think: who watches the watchman?

The scientific method's own error correcting mechanisms also operate on itself. Our understanding of epistemology, repeatability, and falsifiability have evolved alongside and as a result of the scientific method as we have journeyed through mechanics, electromagnetism, statistical physics, and quantum mechanics and relativity. Popper's own seminal work was due to what we have learned from applying the scientific method and on a meta level substantially changed what "science" codified for many of its practitioners.

However, even the need for falsifiability is sometimes suspended (although not lightly and with much criticism) when there is something interesting to pursue like in string theory, where we are operating on energy levels we may never be able to experimentally reach.

Yes, there are some self correcting mechanisms. And of course, sometimes the problem is not in the scientific method but in the people working with it.

This discussion can go on and on, but I'd like to point out the scientific method is not applicable to several things.

String theory like you pointed and other things still in the realm of speculation are one thing (even though their foundation is scientific work)

Getting the best page for 'Cat pictures' on Google is another thing. Or translating a phrase to Japanese.

The success of the scientific method in Physics is due in a big part to the issues I pointed out, physics is constant. The LHC repeats collision experiments thousands of times, so you can get a result with as little variance as possible.

However, it is not possible to test a new drug in millions of people and see what happens, not to mention the results are going to be different for each person, so the best you can have is a statistical answer.

What is the problem to begin with? Science is not some epistemologically omnipotent entity. It is an integral part of human culture and can only be expected to evolve and behave as such. The scientific method is a guiding principle agreed on by its practitioners but that is all that sets it apart from the rest of culture.

The scientific method does work for string theory just like it worked for relativity and other 20th century theories that took a while for experimental confirmation. String theory got a lot of people very excited a few decades ago and so it stuck, just like an artistic or fashion style sticks to a generation or civilization. It is still in the very primal stages, like Newton in the time after the apple metaphorically hit his head, as he was using Kepler's laws to derive classical gravity. This time the math is way more complicated and will take way more time (and likely classical/quantum computational resources) to turn into a theory ready for experimental falsification. Whether or not it truly holds promise or is just a "fad" is irrelevant; the only vector for the evolution science is purely human.

"Best page" is purely subjective. If you draw the analogy between recommendation algorithms and scientific theories, then the person would be the equipment. If you calibrate properly, you should be able to switch out equivalent pieces of equipment and get the same experimental conclusion based on the scientific theory. You can't "calibrate" a person so the primary feedback loop on a recommendation algorithm changes with every user. Until you get down to human psychology and neuroscience, there is really no basis for this problem in what we know of as "science."

As for translation, I'm sure our research of the common threads of language have contributed to translation algorithms (although I have not researched this topic).

Your last point about physics and medicine is moot. Our very basis for "fact" in science is the statistical results of a vast number of experiments. You say that statistics is "the best you can have" as though there is some golden standard to which you are comparing the scientific method to. There is no better golden standard than the statistics naturally built into the science. For all of its imperfections, it is the absolute best method we have for knowing (approximate) truth in a nontrivial way (aka, truth not as we see it in our mind but truth that can be experienced and repeated by the vast majority of humanity given the tools).

Not long ago, we didn't even have a concept of molecules that would act as drugs to impact our health, let alone simulate them in live and computational models (which is growing more and more commonplace) to know exactly how a person's unique biochemistry will react. We will probably always have statistical answers, unless there is some mechanism for nature to reveal "truth" to us. The whole point of science is that those models get more and more accurate over time.

> who watches the watchman?

There's this paranoid viewpoint that Science is this exclusive club shrouded in secrecy, a little like the Masons. They hold on to their established views despite conflicting evidence from the fringes, thus continuing their tenures, fat paychecks, international fame and ultimately control over the world.

There is no watchman. There are scientists. Scientists watch each other with a tenacity that could almost be seen as dogmatic, but really it's because errors help no-one. To become a scientist you do science. If you have a concern about a particular field of science, study up so that you're as knowledgable as those in that field and discourse. That's it!

But science is an (expensive)human endeavor. Tenure committees, grant committees and budget administrators are in a position to elect which paths of research are selected.

Most of the time this is a very good thing as it prevent limited resources from being wasted, but bureaucracies can suffer from groupthink and senior scientists are often reluctant to undermine their career's work. However, the system we have is probably among the best possible. We cannot avoid the problem of the purse strings.

There is a lot of politics in the process of funding science and I would argue the system is quite broken, but it still operates within the scientific community. There may be a new class of hybrid scientists-bureaucrats (aka professors) that have a strong grasp on research direction but they are still scientists. Each individual may have their biases but the sum of all of the scientists is made up of so many different people that the only common link between is their belief in the scientific method and this collective ultimately guides its progress.

Also, I have to nit pick, science is by no means an expensive human endeavor. The net global societal benefit per dollar spent, even with all of the added bureaucracy and other overhead, far outweighs other spending, maybe even spending on education. The problem is that science is long term, something few seem to have the stomach for.

> Tenure committees, grant committees and budget administrators are in a position to elect which paths of research are selected.

True, but their work is still subject to external scrutiny and you don't need tenure to do that.

From my experience in the research department of my university you are quite mistaken.

"External scrutiny" usually means "publish N papers per year and don't get into trouble". Hence the most conservative projects get funding (also because they're more likely to be successful - or better said, easier to do)

And by the way, the majority of the work is done by the graduate/PhD students, and of course their advisor's name is on every paper they publish.

Elegantly described!