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The concept of falsification was introduced by Karl Popper in 1934... not 200 years ago. Popper is a historically important philosopher of science, but under scrutiny much of his thinking doesn't actually match up with how science is done (now or historically), and his philosophy hasn't been the dominant philosophy of science since the 1960s (enter Thomas Kuhn and Paul Feyerabend and Imre Lakatos). Nonetheless, the idea that "science = falsification" permeates popular culture, and is even repeated by many scientists who think about their work, but don't as often think about how they think about their work.

Nevertheless falsification is surely the most coherent justification for scientific reasoning in the sense of "a philosophy professor has a gun to your head and demands that you justify your work as a method for approximating reality"?

As philosophy professors often do.

Rarely in practice, but I'd bet they frequently dream of it, not least when the snotty undergrads ask why they should even bother to study philosophy.

No, if anything falsificationism and scientific realism are in tension. From Popper's The Logic of Scientific Discovery:

> I think that we shall have to get accustomed to the idea that we must not look upon science as a ‘body of knowledge’, but rather as a system of hypotheses; that is to say, as a system of guesses or anticipations which in principle cannot be justified, but with which we work as long as they stand up to tests, and of which we are never justified in saying that we know that they are ‘true’ or ‘more or less certain’ or even ‘probable’.

The most common realist arguments are probably variations on the "miracle argument": our scientific practices work, and the only plausible explanation is that they have at least some ability to find the truth.

This can be said of all of philosophy (at least outside of the purely formal world of logic), not just the physical sciences. From that perspective, 'standing up to tests' is a poor way to evaluate hypotheses, except in comparison to all the others.

Paying attention to falsification also performs the useful task of pushing hypotheses into saying something definitive.

Science is much more than falsification, of course: for one thing, a falsificationist stance does not generate hypotheses on its own.

I'm not suggesting that all of philosophy should adopt falsification as a principle (and much less that it should be ignored if it cannot): ethics, for example, is a field which I think is important beyond what is falsifiable.

Isn’t that a refutation of justificationism, not of realism? Isn’t he just saying that there’s no process you can follow that will guarantee that you haven’t made a mistake, or similarly, that there are no claims which can reach the status of being beyond criticism?

> "a philosophy professor has a gun to your head and demands that you justify your work as a method for approximating reality"?

You probably won't survive that encounter.

falsification provides a philosophical underpinning to science, Kuhn's paradigms provide a description of how science actually is done.

If Popper can be boiled down to science = falsification then Kuhn can be boiled down to Science progresses one funeral at a time.

Popper is more methodology of science, while Kuhn is more protosociology of science. Kuhn’s book doesn’t refute Popper’s, even if he would have liked it to.

I don’t know about the two others, but after reading about them briefly they seem as antirational as any philosophers subscribing to Hegel and/or Marx. When it comes to Lakatos specifically, I can say with certainty that his philosophy of mathematics has so little to do with mathematics that it’s not worth any paper (I studied maths and know many professional mathematicians personally).

> under scrutiny much of his thinking doesn't actually match up with how science is done (now or historically)

Can you elaborate on this?

There are citations both for and against falsificationism at the Stanford Encyclopedia of Philosophy[0]; quoting:

"Popper’s demarcation criterion has been criticized both for excluding legitimate science (Hansson 2006) and for giving some pseudosciences the status of being scientific (Agassi 1991; Mahner 2007, 518–519). Strictly speaking, his criterion excludes the possibility that there can be a pseudoscientific claim that is refutable. According to Larry Laudan (1983, 121), it “has the untoward consequence of countenancing as ‘scientific’ every crank claim which makes ascertainably false assertions”"

From the citation on Hansson, the abstract[1] reads:

"...Furthermore, an empirical study of falsification in science is reported, based on the 70 scientific contributions that were published as articles in Nature in 2000. Only one of these articles conformed to the falsificationist recipe for successful science, namely the falsification of a hypothesis that is more accessible to falsification than to verification."

[0] https://plato.stanford.edu/entries/pseudo-science/#Fals

[1] https://philpapers.org/rec/HANFF

Popper's criterion in a vacuum could seem to be exclusionary, but his philosophy of science involves his underrated idea of evolutionary epistemology. That all theories, seemingly pseudoscientific and the rest, compete to explain something, testable or not. Explanation is the most fundamental aspect, the rival statements compete to solve some problem in terms of how and why.

Read Popper's Ch. 1. Conjectural Knowledge: My Solution of the Problem of Induction https://roamresearch.com/#/app/infinitedays/page/tGbhrzsPK

It's kind of like how the modern standards of mathematical "proof" don't extend backwards very well. Nobody would say that Euler wasn't one of the greatest mathematicians of all time, but much of his work was very unrigorous despite being accepted by the math community long before it was formally verified. Similarly there is lots of science that was settled way before it actually made falsifiable predictions which were confirmed through experiment. The classic example is Newtonian physics, which was contradicted by several observations that were only reconciled by Einstein. Another example would be like Boyle's models of gas and liquid. These models all hold approximately, and are very useful (hence their acceptance), but wouldn't really pass the criterion of falsifiability.

Kuhn frames it as "anything goes", which is supposed to be what the horrified scientist utters to themself as they peruse the historical record of their field. Scientists tend to go with "whatever works best" (and whatever secures more funding), rather than following a strictly falsificationist paradigm.

More and better context here: https://www.nature.com/nature-index/news/the-idea-that-a-sci...

Which ought to be a good reminder that the philosophy of science is a branch of philosophy, not science.

Similarly the problem of induction is a problem for philosophers, not scientists: scientists have a method of doing science that works, and has created a modern world, with all sorts of popular things like televisions and smartphones. However, despite the fact that we’re next door neighbors to philosophy, sometimes borrow their tools, and even have some roots in “natural philosophy,” the best tool we have—the one that makes it all useful to society at large—seems to be the one that their framework says can’t be justified.

When your framework with a long history and lots of proponents seems to indicate that a single little project is not well grounded, that project has a problem. When it seems to indicate that the grand project which underpins all of modern society is not well grounded, the framework has a problem.

Philosophy of science is philosophy, not science. Kuhn, Lakatos, etc, however, muddied the waters a bit by introducing the notion (at least implicitly) that philosophy of science should consider how science is actually practiced, which looks like a scientific approach to me.

I think science and philosophy of science would both improve if there was less separation between the fields. Many, if not most, practicing scientists have a Doctorate of Philosophy in a scientific field, yet none of the graduate programs that I'm aware of require a single course in philosophy of science. Equally problematic, I'm not sure how many philosophers of science have actually taken the time to empirically discover anything.

Popper didn't equate science with falsification. That's a gross simplification that's often pushed (I once believed that myself) yet doesn't actually hold up (once you put his thinking under scrutiny)

As a scientist, I'm glad you mention Lakatos, as he described science in a way that is recognizable to practitioners, yet is more philosophical than Kuhn (more a sociologist of science). He significantly impacted how I practice science and evaluate theories (and research programs).

Lakatos is interesting because his philosophy tried to rescue Popper's philosophy in light of Kuhn's arguments, but mutated it considerably in the process.

Gelman (http://www.stat.columbia.edu/~gelman/research/published/phil...):

"The classical or frequentist approach to statistics (in which inference is centered on significance testing), is associated with a philosophy in which science is deductive and follows Popper’s doctrine of falsification. In contrast, Bayesian inference is commonly associated with inductive reasoning and the idea that a model can be dethroned by a competing model but can never be directly falsified by a significance test. The purpose of this article is to break these associations, which I think are incorrect and have been detrimen- tal to statistical practice, in that they have steered falsificationists away from the very useful tools of Bayesian inference and have discouraged Bayesians from checking the fit of their models."

Well that is not really what the article is about. It's more about the problem of induction itself, and the problems of its use as basis for both Science and Philosophical endeavors. The article only made a flimsy drive into the subject, and the Wikipedia article does a much better job.

"Problem of induction" - https://en.wikipedia.org/wiki/Problem_of_induction

"...First formulated by David Hume, the problem of induction questions our reasons for believing that the future will resemble the past, or more broadly it questions predictions about unobserved things based on previous observations. This inference from the observed to the unobserved is known as "inductive inferences", and Hume, while acknowledging that everyone does and must make such inferences, argued that there is no non-circular way to justify them, thereby undermining one of the Enlightenment pillars of rationality..."

To address your surprise, the article was attempting to focus on just induction while falsifiability is more the higher level https://en.wikipedia.org/wiki/Demarcation_problem , but admittedly, philosophy of science topics do overlap a lot.

> Since we're talking about induction as the basis of science, I'm surprised the concept of "falsification" wasn't mentioned, which has been the "workhorse" of most science during the past two hundred years.

An article on the subject of falsifiability and Popper was also published on the site (and posted on HN by me within minutes of this one):

https://news.ycombinator.com/item?id=36951476

I wouldn't oppose Bayesian statistics to Falsificationism but to Frequentism.

The benefit of the Bayesian approach is the need to explicitly state a prior distribution, in this case, you would need to state the prior probability that all ravens are black. This forces us to realise that induction does not prove anything, and reduces to the matter of having the evolutionarily-gifted skill of coming up with good priors.

> induction does not prove anything

Another benefit of a Bayesian approach is that you stop trying to "prove" things.

Bayenism is great for things that doesn't require explanations it's horrible as a method for knowledge creation.

Bayesianism is the only reliable way of creating knowledge, as it is the direct application of the mathematics of probability. All frequentism can do is tell you how poorly your data fits an unrealistic straw-man model.

Probability is not knowledge creation.

Then you must reject all science, as the knowledge gained is based on probabilistic experiments.

No science is based on explanations that are hard to vary (i.e. explain what they purport to without any competing explanations).

We use scientific experimentations not to prove but to rule out alternative theories.

I can explain why a given thing will act a certain way. I don't need probabilities for that.

If I need probability it's because I am just guessing and nothing else.

If I need them I am just dressing up guessing in fancy words. But I am just that.

Important to distinguish Bayesian epistemology (the idea that knowledge comes from induction) from Bayesian techniques in statistics. Karl Popper’s epistemology (critical rationalism) refutes the former, but does not mind the latter.

Popper would agree that Bayesian techniques are useful (and even powerful) tools in statistics and practical problem-solving. But he would say that Bayesian ideas are insufficient to understand how knowledge grows and progresses. From a critical rationalism viewpoint, knowledge grows through conjecture and refutation - the proposal and testing of new explanatory theories. Bayesian statistical approaches can be part of the toolkit to falsify those theories, but they can’t explain how they come about, so they aren’t adequate as an epistemology. Popper’s critical rationalism may not be entirely complete, but it seems far better as a starting point for explaining how we get knowledge (which is what an epistemological framework needs to do) than Bayesian ideas about measuring truth statistically. Major breakthroughs like relativity and quantum entanglement are evidence for this: they required conjectures that at first seemed at odds with what we had observed. Physicists had to follow rational theories down very strange paths before any empirical confirmation, eventually to create new explanations that allowed us to model and predict distant cosmological events that had previously appeared random to us.

If anyone is interested in these ideas (which are still fairly new to me; sorry for anything I’m expressing poorly), I highly recommend reading The Beginning of Infinity. It is an exciting, wide-ranging study of Popper’s epistemology by the guy who ‘invented’ quantum computing. It also discusses the ‘many universes’ theory, which is fascinating.