Just read Karl Popper, these people basically tell us, it's all there.
I am baffled by the sheer irrationality of this thinking. The answers to the real scientific questions may only be settled by actual scientific evidence. And Popper has presented zero amount of this evidence. And so did Kuhn. And every other philosopher. What is the scientific value of a critic of physics or string theory? Zero, nada, nothing. Philosophers just talk, scientists do actual science. These activities have been separated for thousands of years. Scientists aren't assistants of philosophers who just complete some details about the philosophers' great visions. Scientists use their, scientific method to settle the biggest questions, too.
If you open Popper's Wikipedia page or a similar source, you will be told:
He was an anti-dogmatist: discussions should be absolutely free, any claim should be criticized. A good theory is one that may be falsified. He vigorously refused previous models of science such as inductivism.A good new set of the rules of the game. Every rational person may agree at some point. He was fighting against things like Stalinist history or Freudian psychology that don't really say anything – and any observation is spun so that the proponents of the Stalinist and Freudian histories always say that they were right, anyway. The global warming hysteria is a top contemporary example of this activity that isn't science for Popper's reason. Is it cold? Snowing? Raining? Rainbow? All weather events confirm the catastrophic global warming. The world will be over in 12 years. Sure.
However, Popper rightfully pointed out that everything should be criticized. In particular, Popper's claims themselves should be criticized. And there are tons of reasons to do so. We should primarily notice what he was against; whether his principles may be safely applied without any limitations; and how they're actually being applied by various people.
What he was against was "inductivism", the old model of science. It was started by another, much older philosopher, Francis Bacon – a man who is sometimes considered a founder of the empirical sciences among the philosophers. You propose a law that generalizes some observations, test it, adjust it, invent a more general and stronger law, and eliminate disconfirmed laws.
Bacon had this picture. Was it worse than Popper's picture? I don't know. Bacon wrote these things in 1620, over three centuries before Popper's texts. In spite of that, Bacon's comments look as usable to me as Popper's. In particular, Bacon also knew it was important to eliminate falsified theories.
In fact, the Wikipedia page on inductivism tells you that the contemporary update of inductivism is Bayesianism. What is better, Popperism or inductivism? And Popperism or Bayesianism? I think that the first contest is a close call. In the second one, I choose Bayesianism as the better choice. One invents hypotheses about the real world, gives them some prior probabilities that are fair enough – that don't exclude any possibility a priori – and updates the probabilities by the Bayes theorem exploiting the evidence.
Why is Bayesianism more rational than Popperism? Because it treats the possibilities more fairly or more impartially. According to Popper, every scientific theory must be at risk. The theory must say:
Look, I am a witch for a while. You will have fun trying to burn the witch. There is a credible chance that you will burn me. I will be important if I survive.It's brave, it's an exciting game, it makes a good story or something – there are probably emotional reasons why some people are obsessed with this Popperist paradigm. The problem is that if the scientific theory, principle, statement, or framework isn't willing or ready to undergo this very special ritual and risk this kind of suicide, the scientists must still believe something. In practice, they have to believe some other theory that hasn't faced this risk of being burned, at least not recently.
It is just totally unfair! Some poor theories and hypotheses are treated as witches (or worse, if they refuse to take on the fake nose) while the other, preferred ones are the mob that burns the witches. And everyone in the mob is assumed of being right and fair.
The point is that Popper's obsession with "falsification" turns some potential theories to witches while others are accepted as default truths without any risk of fire. So there's a huge room for a biased person to choose which beliefs must face existential risks – and which beliefs don't have to. That's just wrong. Bayesianism fixes it.
In Bayesianism, falsification is still important. It kills most of the alternatives. Most of the useful evidence is still "negative" – responsible for the falsification of many alternative hypotheses. On the other hand, the status of many competing theories – e.g. "there exists no multiverse" vs "there exists the multiverse" – is basically symmetric and Bayesianism fairly and correctly reflects this symmetry. In such situations, "positive" and "negative" evidence is basically equally legitimate and possible. The obsession with "falsification" is just wrong in many such qualitative and conceptual cases.
The asymmetry underlying the Popperist approach is a huge bug that may be abused – and it is being abused all the time. A typical example is the comparison of the validity of two frameworks, quantum field theory and string theory. The Popperazzi just choose string theory as the alternative that is "obliged" to become a witch and face the risk of being burned – while quantum field theory is accepted as the "default truth", without any risks. In reality, both frameworks – quantum field theory and string theory – are consistent with the well-known observations, once some extra choices are made to turn the framework into a specific viable model. String theory also predicts quantum gravity so it is clearly superior.
But the Popperazzi deny everything. They just abuse the power that the Popperist approach gives them and pick the winner – as quantum field theory. And then they use the Popperist ideology to sling mud on all alternatives. This behavior shows that they lack either rationality or integrity or both. But Popper may really be blamed for this behavior because his skewed ideology almost unavoidably leads to this mess. The value of philosophers' ideas may be seen when these ideas are being oversimplified by the primitive folks. As Jesus said, if He existed, "you will know them by their fruit".
And the dishonest, irrational critics of string theory must be considered fruits of Karl Popper's tree. If we pick this particular example, the assertion that "quantum field theory is the final word forever" is a great example of a statement that has been turned into a dogma among certain people by the "anti-dogmatist" ideology of Karl Popper's! When he tells them "attack and question everything", people sort of overlook that it unavoidably means that "some things" will not be questioned at all – because the questioning of them could be interpreted as a failure to question the things that must be mainly questioned!
The more general problem of this "thinking revolving around philosophers" is the incredible overstatement of the power of some philosophical propositions. If we look at the question whether the multiverse exists, to pick an example, one answer might be "more aligned" with Popper's statements than the other. Science is "more falsifiable" if the multiverse doesn't exist. Does it mean that the multiverse doesn't exist? It clearly doesn't. When it comes to this question, Popper's assertions may be positively or negatively correlated to the scientific truth. There exists absolutely no reason to assume that the correlation should be positive, that Popper's statements could be a good key to pick the correct answers to big questions in theoretical physics or cosmology.
Everyone whose thinking is at least slightly scientific understands this elementary assertion of mine. Popper and any other philosopher is just useless in answering well-defined, technical (albeit deep) questions about physics. If they succeeded once, they may succeed or fail next time. To think that Popper's verses could be used to answer cosmological questions is isomorphic to the idea that you should learn your cosmology from the Bible. It just can't be the case. Some theories may be more deterministic (like classical physics is more deterministic than quantum mechanics) or more falsifiable (like cosmology without the multiverse) or otherwise "more philosophically pleasing" than their alternatives, according to one or another definition of "philosophically pleasing". But when a theory is more philosophically pleasing, it doesn't mean that it is more likely to be true. You don't find the theory sufficiently philosophically pleasing? Go somewhere else. It's ultimately hard scientific evidence – observations and calculations – that direct us towards the scientific truth and that may be used to evaluate the philosophers' guesses. It's totally and self-evidently silly to think that philosophers' guesses may be used to evaluate the validity of scientific theories or the value of research projects.
Maybe Popper's or another philosophy is useful when you're preparing to do research in the first place. But thinking that detailed, technical questions about inflation or its alternatives could be answered by looking at Popper's or philosophers' books is self-evidently ludicrous. One would be using philosophy well outside its domain of validity. And it's questionable whether there is any overlap in the domain of validity of science and philosophy at all.
As an anti-dogmatist, Popper also liked to say that
everything should be criticized.Great. You're open-minded, there are no dogmas. One may agree with it in many contexts. The problem is that many people unavoidably take this wisdom literally and use it in contexts where it is no longer justified at all. And they're unavoidably applying this principle in a biased way as well. Because they are the defenders of the view that "everything should be criticized", they believe that they have an exception. They believe that they cannot be criticized, after all!
(Well, this is really how the contemporary cultural Marxist quasi-totalitarianism grew. It was made out of people who were constantly criticizing pillars of our civilization because criticisms are so great. The only problem is that when it comes to criticisms that are really important, especially criticisms of the cultural Marxism itself, they suddenly forget about the value of criticism. It's unavoidable that the excessive worshiping of criticisms is ultimately used in a skewed, one-sided way. Analogously, excessively loud "fight against racism" was bound to become racism itself, too. And there are many similar examples. Those who manage to be appointed as the enforcers of something whose importance is overstated in this striking way unavoidably become the new dictators.)
So Popper's statement that "everything should be criticized" is unreasonably biased and excessively strong. A fairer statement of this kind would say:
It should be allowed to question the propositions and theories to the extent that is an increasing function of the probability that they could be wrong.Decent readers must immediately see that Popper's statement and my statement talk about the same issue, Popper's statement is the fanatical and one-sided one, while my is the fair and neutral one. Again, when one dogmatically uses Popper's principle about "criticizing everything", he unavoidably gets the "power" to pick which things should be criticized and which things shouldn't. But as far as people think rationally, these decisions aren't made by individual people arbitrarily. They are made or should be made according to the available evidence.
The very statement that "everything should be criticized" indicates that he has preferred to disrupt and undermine everything – like Trotsky and his permanent revolution. Is that a good thing? Even this isn't really a good thing in general. Science wants breakthroughs but at the same moment, scientists must also be conservative, sometimes radically conservative. They just don't want to throw away successful or elegant theories unless there are good reasons to do so. There is nothing wrong about this conservatism. This conservatism has been utterly successful and it is also highly rational. Extraordinary statements require extraordinary evidence. And if the available evidence doesn't change (much), scientists' beliefs don't change (much), either. Isn't it clearly a basic axiom of rational thinking? People can ignite "paradigm shifts" but among scientists, it may happen only when they really discover something nontrivial.
The statement that some successful theory or framework (e.g. quantum mechanics) should be abandoned is an extraordinary statement – and that's why it requires extraordinary evidence. It seems that Popper's quote may be used – and is often being used – to beat this principle. Because everything should be criticized, it's great if you start to emit tons of critical gibberish about quantum mechanics, just for fun. And hundreds of clueless people are doing that – and writing hundreds of scientifically nonsensical books. It's not great at all. Again, Popper's statement about the criticism of everything ultimately has the effect of eroding the power of scientific evidence in general – which makes the people more dogmatic about their prejudices and more blind towards the evidence.
Although Popper could have been a real honest opponent of dogmatism, he wrote down some statements that are really one-sided, extreme, and that are unavoidably being interpreted in an oversimplified way and abused to justify Poppers' fans' prejudices and misconception and to ignore the scientific evidence. When all these expected effects and other effects of Popper's writing are added, I believe that Popper's contribution to the scientific research is negative.
In this essay, I've argued that "applied Popperism" is counterproductive for two main reasons:
- it places some intriguing but problematic ideological slogans above the old-fashioned fairness in comparing several competing ideas – but fairness should always be more important
- it turns the "enforcers" of these slogans into too powerful folks who could decide about too many things, who could indefinitely justify their own prejudices, and who would effectively be uncriticizable