Can a non-scientist test a hypothesis

Contradictions that we have to endure : What science, politics and the public can learn from the corona crisis

Dieter Lenzen has been President of the University of Hamburg since 2010 and was previously President of the Free University of Berlin. He is a professor of education.

What applies to every crisis applies to the corona crisis: It is both a challenge and an opportunity. At the moment we're only talking about the challenge that needs to be overcome and maybe also about how everything will be the same as before.

But it won't, and it shouldn't. Scientific research must learn from the crisis. Because there are many people who lose their trust in science, virology.

Scientific results are contradictory - not everyone can endure

The reason: The results they read and hear about are contradicting, every day they read about new results, from "studies": "A study by the university ... has shown that ..."

Result: They no longer listen, they do what they want, no matter what the cost. Or they listen to so-called conspiracy theories of the left, the right: the Jews are to blame, the Muslims, the government anyway, of course science too, and actually there is no coronavirus.

Scientific research cannot help but produce different results. To “agree” on something is not the way to get to the truth.

An example from everyday life

We know this from everyday life: a child lies in bed and feels bad. Parents wonder what the cause could be. They proceed in exactly the same way as researchers: they set up a theory (our child suffers from a flu-like infection) and derive a hypothesis (if our child has a flu-like infection, it should have a high temperature, reddened tonsils and perhaps a cough) .

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Then they begin with the “scientific examination”: They measure a fever, look into the throat and listen to see whether the child is coughing. If you find that none of this is the case, dismiss this hypothesis.

In science this means: You have falsified the hypothesis (our child has a flu-like infection). The hypothesis was wrong. Then the parents set up a new theory (our child has upset his stomach), derive hypotheses (child should vomit), investigate (questionnaire: "Have you vomited?") And either falsify that again, or they are successful Child vomited.

This is how the exclusion of theories works in medical practice

The theory could not be refuted. It could be a gastrointestinal infection. But that does not mean that this theory is correct. It's just not wrong.

Most people cannot tell the difference. Parents, if responsible, will propose other theories about the cause of their child's illness, and they will try to falsify these too.

You may call in other experts, the doctor who tries to falsify it on your own. His bill will therefore also include: Exclusion of an XY disease.

That means: Even medical professionals try in everyday life, at least in more demanding cases, to refute theories (XY disease) so that they do not treat a disease that the patient does not even have.


It is the same with scientific research: In Wuhan people die, the theories that it is a known disease are first tried to refute, at some point someone suggests that it might be a new virus and that the research apparatus becomes started.

The different theories about mouth and nose masks

This also applies to the theories publicly expressed by virologists, infectiologists, epidemiologists, the Robert Koch Institute or the Minister of Health. Example: A mouth and nose mask is of no use to anyone in everyday life (January 2020) or: Such protection prevents the virus from spreading to others (March 2020), or: The mask is of benefit to others and the wearer (May 2020).

This is apparently contradictory, but no reason to turn away from science, it cannot be otherwise: The thesis that a mouthguard is not useful to anyone was put to the test and refuted and a new one developed (the mask is useful for others), until this, too, was refuted, in favor of the thesis that it would benefit both. Scientific knowledge is always preliminary.

Politicians have to decide and take responsibility

So what can we learn from the corona crisis with regard to our research operations and do better in the future? What can those learn who are not themselves scientists?

The politicians: They have to decide and take responsibility, and they cannot justify themselves by referring to recommendations from scientists, which are always tentative.

You can only draw the conclusions yourself from the theses of science, which could not be refuted at a certain point in time. They bear the risk because they are democratically elected.

The people out there: They have to understand that different scientific findings are not contradictory and therefore irrelevant, but that they always have to look at the latest scientific findings that have overtaken others. That is why Greta Thunberg's sentence that one should listen to "science" is also wrong. These do not exist: there are only ever results that overtake others.

This also applies to climate research, which has produced very different results in its history, from the claim that it is getting warmer all over the world to the more cautious claim that there is climate change, but not uniform warming, to the forecast of new ice ages.

Not every "study" is worth mentioning

There is that in every science and sometimes the result depends on interests. It has been argued that human talent is innate or, on the contrary, acquired. Interestingly, the theory of employment always had a boom when one needed more qualified workers and wanted to generate the willingness to spend more money on education, because talent could be influenced by school.

The media: They have to learn that they have to forbid certain sentences. For example: "It has been proven that ..." or "A study by the university ... has shown that ...". And: not every study is worth mentioning.
Many studies have serious methodological errors because they are carried out too quickly or with too little money.

Those who cannot judge should not write articles about scientific results that themselves cause irritation among people or politicians.

The media have as much responsibility as politics

The media have at least as much responsibility as politics, because they stimulate the latter to make hasty decisions, since after all "a study has shown that ...". The media have an educational mandate, not one that causes confusion through ever new, self-unchecked allegations.

And finally the science itself: She shares responsibility for wrong decisions if she lets herself be carried away by political recommendations for action and does not clearly distinguish between knowledge and recommendation (the daycare centers should / should not be opened immediately / not at all; returnees from abroad should / should not remain in quarantine for 14 days).

Researchers who want to publish preliminary results faster than usual in times of crisis in order to give helpful advice to politics and society should be aware of the small degree on which they are walking.

Can we really already derive a recommendation from preliminary knowledge? Should we hold back our still shaky hypotheses so that hasty conclusions are not drawn?

Our level of knowledge is always preliminary

The answer is basically obvious: in science there are never any final findings, the state of knowledge is always provisional. Communicating this and weighing up the right timing and wording of any recommendations that have been pronounced, which may have to be modified in the next step in knowledge - that is the fine art of science communication.

The virologist Christian Drosten has mastered them, and for enlightened people it is always beneficial to accompany him. And a horror to see how it is deliberately misunderstood.

With all of this, science must always ask itself the question of the relevance of its research subjects. The social behavior of sausage buyers in front of a chip shop is simply not a meaningful subject - it actually existed! We have other worries somehow.

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