Free Speech, Science / Tech, Top Stories

The Scientific Importance of Free Speech

Editor’s note: this is a shortened version of a speech that the author was due to give last month at King’s College London which was canceled because the university deemed the event to be too ‘high risk’.

A quick Google search suggests that free speech is a regarded as an important virtue for a functional, enlightened society. For example, according to George Orwell: “If liberty means anything at all, it means the right to tell people what they do not want to hear.” Likewise, Ayaan Hirsi Ali remarked: “Free speech is the bedrock of liberty and a free society, and yes, it includes the right to blaspheme and offend.” In a similar vein, Bill Hicks declared: “Freedom of speech means you support the right of people to say exactly those ideas which you do not agree with”.

But why do we specifically need free speech in science? Surely we just take measurements and publish our data? No chit chat required. We need free speech in science because science is not really about microscopes, or pipettes, or test tubes, or even Large Hadron Colliders. These are merely tools that help us to accomplish a far greater mission, which is to choose between rival narratives, in the vicious, no-holds-barred battle of ideas that we call “science”.

Marshall and Warren, 1984

For example, stomach problems such as gastritis and ulcers were historically viewed as the products of stress. This opinion was challenged in the late 1970s by the Australian doctors Robin Warren and Barry Marshall, who suspected that stomach problems were caused by infection with the bacteria Helicobacter pylori. Frustrated by skepticism from the medical establishment and by difficulties publishing his academic papers, in 1984, Barry Marshall appointed himself his own experimental subject and drank a Petri dish full of H. pylori culture. He promptly developed gastritis which was then cured with antibiotics, suggesting that H. pylori has a causal role in this type of illness. You would have thought that given this clear-cut evidence supporting Warren and Marshall’s opinion, their opponents would immediately concede defeat. But scientists are only human and opposition to Warren and Marshall persisted. In the end it was two decades before their crucial work on H. pylori gained the recognition it deserved, with the award of the 2005 Nobel Prize in Physiology or Medicine.

German physicist Max Planck

From this episode we can see that even in situations where laboratory experiments can provide clear evidence in favour of a particular scientific opinion, opponents will typically refuse to accept it. Instead scientists tend cling so stubbornly to their pet theories that no amount of evidence will change their minds and only death can bring an end to the argument, as famously observed by Max Planck:

A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

It is a salutary lesson that even in a society that permits free speech, Warren and Marshall had difficulty publishing their results. If their opponents had the legal power to silence them their breakthrough would have taken even longer to have become clinically accepted and even more people would have suffered unnecessarily with gastric illness that could have been cured quickly and easily with a course of antibiotics. But scientific domains in which a single experiment can provide a definitive answer are rare. For example, Charles Darwin’s principle of evolution by natural selection concerns slow, large-scale processes that are unsuited to testing in a laboratory. In these cases, we take a bird’s eye view of the facts of the matter and attempt to form an opinion about what they mean.

This allows a lot of room for argument, but as long as both sides are able to speak up, we can at least have a debate: when a researcher disagrees with the findings of an opponent’s study, they traditionally write an open letter to the journal editor critiquing the paper in question and setting out their counter-evidence. Their opponent then writes a rebuttal, with both letters being published in the journal with names attached so that the public can weigh up the opinions of the two parties and decide for themselves whose stance they favour. I recently took part in just such an exchange of letters in the elite journal Trends in Cognitive Sciences. The tone is fierce and neither side changed their opinions, but at least there is a debate that the public can observe and evaluate.

The existence of scientific debate is also crucial because as the Nobel Prize-winning physicist Richard Feynman remarked in 1963: “There is no authority who decides what is a good idea.” The absence of an authority who decides what is a good idea is a key point because it illustrates that science is a messy business and there is no absolute truth. This was articulated in Tom Schofield’s posthumously published essay in which he wrote:

[S]cience is not about finding the truth at all, but about finding better ways of being wrong. The best scientific theory is not the one that reveals the truth — that is impossible. It is the one that explains what we already know about the world in the simplest way possible, and that makes useful predictions about the future. When I accepted that I would always be wrong, and that my favourite theories are inevitably destined to be replaced by other, better, theories — that is when I really knew that I wanted to be a scientist.

When one side of a scientific debate is allowed to silence the other side, this is an impediment to scientific progress because it prevents bad theories being replaced by better theories. Or, even worse, it causes civilization to go backward, such as when a good theory is replaced by a bad theory that it previously displaced. The latter situation is what happened in the most famous illustration of the dire consequences that can occur when one side of a scientific debate is silenced. This occurred in connection with the theory that acquired characteristics are inherited. This idea had been out of fashion for decades, in part due to research in the 1880s by August Weismann. He conducted an experiment that entailed amputating the tails of 68 white mice, over 5 generations. He found that no mice were born without a tail or even with a shorter tail. He stated: “901 young were produced by five generations of artificially mutilated parents, and yet there was not a single example of a rudimentary tail or of any other abnormality in this organ.”

These findings and others like them led to the widespread acceptance of Mendelian genetics. Unfortunately for the people of the USSR, Mendelian genetics are incompatible with socialist ideology and so in the 1930s USSR were replaced with Trofim Lysenko’s socialism-friendly idea that acquired characteristics are inherited. Scientists who disagreed were imprisoned or executed. Soviet agriculture collapsed and millions starved.

Henceforth the tendency to silence scientists with inconvenient opinions has been labeled Lysenkoism since it provides the most famous example of the harm that can be done when competing scientific opinions cannot be expressed equally freely. Left-wingers tend to be the most prominent Lysenkoists but the suppression of scientific opinions can occur in other contexts too. The Space Shuttle Challenger disaster in 1986 is a famous example.

The Space Shuttle Challenger disaster happened because the rubber O-rings sealing the joints of the booster rockets became stiff at low temperatures. This design flaw meant that in cold weather, such as the −2 °C of Challenger launch day, a blowtorch-like flame could travel past the O-ring and make contact with the adjacent external fuel tank, causing it to explode. The stiffness of the O-rings at low temperatures was well known to the engineers who built the booster rockets and they consequently advised that the launch of Challenger should be postponed until temperatures rose to safe levels. Postponing the launch would have been an embarrassment and so the engineers were overruled. The launch therefore went ahead in freezing temperatures and, just as the engineers feared, Challenger exploded, causing the death of all seven crew members.

NASA’s investigation into the Challenger disaster was initially secretive, as if to conceal the fact that the well-known O-ring problem was the cause. However, the physicist Richard Feynman was a member of the committee and refused to be silenced. At a televised hearing he demonstrated that the O-rings became stiff when dunked in iced water. In the report on the disaster he concluded that ‘For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.’

Today, there are many reasons to be concerned over the state of free speech, from the growing chill on university campuses to the increased policing of art forms such as literature and film. Discussion of scientific topics on podcasts has also attracted the ire of petty Lysenkoists. But there is also cause for optimism, as long as we stand up for the principle that no one has the right to police our opinions. As Christopher Hitchens remarked. “My own opinion is enough for me, and I claim the right to have it defended against any consensus, any majority, anywhere, any place, any time. And anyone who disagrees with this can pick a number, get in line, and kiss my ass.”


Adam Perkins is a Lecturer in the Neurobiology of Personality at Kings College London and is the author of the book The Welfare Trait: how state benefits affect personality. Follow him on Twitter @AdamPerkinsPhD


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  2. Andy D says

    In fact that means “God’s truth conquers” which, although I guess you are agreeing with the sentiment of the writer, as I do myself, may not be entirely apt given the multitudinous examples of interference by religious entities in the pursuit of scientific knowledge, as with the condemnation of Galileo by the Roman Catholic Inquisition for his support of heliocentrism, the condemnation of Darwin by the Church of the England and the continuing pursuit by many for the teaching of creationism in schools etc.

  3. cacambo says

    Actually, the history of science is replete with examples that falsify Planck’s quip about science proceeding one funeral at a time. It turns out scientist are quite willing and able change their minds when presented with good arguments. (On this, see Dan Sperber and Hugo Mercier, The Enigma of Reason, chap. 18). This is good news, of course, and actually strengthens the author’s point about the need for free speech for scientists–and everybody else!

  4. Caligula says

    Perhaps the best Orwell quote on free speech is, “Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.”

    As for the space shuttle, O-rings that become stiff when cold isn’t necessarily a “design flaw” any more than a “never exceed” speed is a design flaw in an airplane. Practically all engineered devices are designed to work within a specified thermal environment.

    As for the Space Shuttle, it lived at the intersection of engineering and politics. To get the program approved and funded, promises were made which could not be met. Such as, “The Shuttle will cost less than expendible space rockets,” and “it’ll be the ‘DC-3 of Space’.”

    Yet the Space Shuttle program had enormous fixed costs, and therefore achieving per-launch cost targets could be done only with frequent launches. And therefore enormous pressure to just approve the launch on that fateful day, even though the temperature that day was well outside the vehicle’s thermal specifications.

    And did you think those who do commercial engineering are not subject to similar pressures if/when performance is over-promised when a project is approved? Such conflicts will always exist in commercial engineering, and if you can’t handle this, well, didn’t a former U.S. president say something about staying out of the kitchen if you can’t stand the heat?

    As for “DC-3 of Space,” few would have bought tickets to fly on DC-3s if the risk of death had been over one percent per flight. And so NASA paid people to do “analyses” that showed a near-infinitesmal probability of catastrophic failure, analyses which today are beyond risible and well into “how could they possibly have thought that?” territory. This, however, belongs more to the “will-to-believe because-I-want-to-belive” school of bad science than to “you can’t say that” free speech limitations.

    Free speech limits in science today tend to be in areas regarding human potential, such as gender and IQ, where it can be career-ending to question certain political orthodoxies. This is possible because, with sufficient political power, people can be made to publicly espouse just about anything. For example, do you really want to risk your job by asserting that even if there were perfect equality of opportunity there likely would not be anything close to proportional representation in many human endeavors?

    Whereas if you insist a machine can safely operate outside its thermal design specifications, or that using it is orders of magnitude safer than it actually is, you are likely to be proven very spectacularly wrong.

  5. Bill says

    You make good points even if some examples are flawed as pointed out by prior commentators. I wanted to provide my hypothetical:

    The climate evangalists insist it is man-made CO2 causing “climate change” based upon their mathematical models and cry out heresy, slander, defame, and otherwise silence anyone to criticizes that hypothesis (not a fact since the models have never accurately predicted reality). What if the real cause of climate change isn’t CO2 but another element from industrialized man, specifically, the accelerating use of rare metals for batteries? Of course, anyone hypothesizing and seeking a grant to study this is quelled and silenced, and the climate evangalists drive their anti-CO2 agenda which includes things like EVs which amplifies the mining and processing of the rare metals which is actually the driver. I think this hypothetical illustrates the (at least my) frustration at times.

    • Alex Russell says

      Climate change being caused by human released CO2 isn’t a very good example of a theory that is clutch to without good evidence as there is overwhelming evidence that one, CO2 is a key driver of the current global climate change, and two human activity is the main source of this CO2.

      People do dispute these facts, they are not being silenced. Just read/watch any right leaning USA media source and you will find a torrent of dissent. The main problem with their claims is a lack of any reasonable alternative theory being put forth. I’m just not buying that global climate change can’t be happening because God promised that the “flood” would be the last global catastrophe.

      A better example might be the current physics debates between the various attempts to explain the “real world” interpretation of “wave collapse” in quantum physics: Copenhagen interpretation, many-worlds interpretation, the De Broglie–Bohm (pilot-wave) interpretation, and quantum decoherence theories.

      • Bill says

        The dispute is met with slander and the gatekeepers of the grant money were some of those generating the slander. Do you really think that the EPA would grant a climate researcher money for a study showing that man-made CO2 was NOT the driver of climate change after it was so heavily invested in regulations purporting just such a causal link?

        (FYI, for your “overwhelming evidence” — i’d wonder if it’s so convincing, why have none of the predictions come true from the models, and why is it necessary to go back in time and “fix” the actual, historical physical measurements by replacing them with extrapolated values where all adjustments are shifting the historical measures downward. In 5 years, even this years’ recorded temperatures will be shifted down so it is no longer the “hottest on record?” In most fields of science, actual hard-measurements aren’t adjusted since they are how you grade your models for accuracy.)

        As to your second point, those in disagreement ARE being silenced. Just because “oh, you can say it in your own home and in private” doesn’t mean it isn’t being silenced. The academics who based their entire careers on the man-made-CO2 hypothesis control the peer reviewed journals. As a result, researchers who uncover alternative (complementary or disputing) causes find their submissions thrown in the waste bin. If they can’t publish, they can’t get tenure, and it’s harder to get grants for further research. Your argument that it isn’t silencing them is the equivalent of saying you aren’t silencing the homosexuals by refusing them a marriage license in the US, after all, they can still get married in Canada. You aren’t refusing that lesbian couple a wedding cake, after all, they can still get one at the store down the street. You aren’t refusing that person from stating that he is a proud supporter of President Trump by wearing a MAGA hat, you just don’t have a problem with thugs car-jacking him or throwing eggs at her or punching them in the face.

        Freedom of speech IS being silenced when saying something counter to the prevailing acceptable thoughts is met with the lynch mob and pitchforks calling for ostracising, fire them, shut down and boycott the store, etc. Both sides do it, and it’s wrong regardless.

        • TarsTarkas says

          The whole point of the e.mails exposed in the Climategate scandal were to suppress the publication of papers that did not support the CO2 global warming narrative in order to create a positive feedback loop of consensus science. ‘Look, there aren’t any papers being published disproving global warming, therefore it’s true!”

          Another good example of the Science Establishment suppressing contrary ideas that proved to be correct include the ostracizing and condemnation of J Harlan Bretz regarding the origin of the ‘Spokane Floods’, when he showed that repeated catastrophic floods caused by glaciers damming glacial lakes were the source of the scoured terrain of eastern Washington and Oregon. Fortunately he got his just recognition while still alive.

      • Skippy Kipling says

        “The main problem with their claims is a lack of any reasonable alternative theory“

        This is both untrue and beside the point.

        First, there is no evidence that the earth’s climate is changing at an unusual rate. By what metric do you make that assertion? The earth has warmed and cooled many times, and often at rates far more rapid than the 20th century’s modest 1 degree warming. Moreover, the correlation between atmosphere temperature and CO2 levels is weak—on both long and short timescales.

        Second, the absence of an alternative theory in no way makes a theory valid. The burden of proof lies on those who make a claim, not those who dispute it.

      • scott allen says

        Actually they are being silenced, prominent politicians have called for trials of non believers, a professor said deniers should be put to death, try to get funding for studying nature caused global warming and you will be eating a soup kitchen.
        And there are numerous other hypothetical causes for global warming, including the latest that the ozone depletion caused the warming and now the pause in warming is due to the closing of the ozone hole. The one that is most likely is the sun is dimming or going thru a quiet phase as the earth has not received the same amount of watts per square meter.
        If you wish to mock a religion ,mock the worshipers of global warming, their religious leaders claimed that the seas would be dead, Manhattan would be under water, the Arctic would be ice free, the list could on and on. Millerism is not dead but alive a doing well under the advocates of global warming.

  6. Christoper Hitchens stated, “I am no longer a socialist, but I still am a Marxist.” That’s not good enough. We must put an end to dhimmitude in Western academia and its forced conversions of scientific skeptics to the pagan god of global warming alarmism.

  7. John McCormick says

    Don’t forget Alfred Wegener’s idea of continental drift. He and anyone who did work that could support the idea suffered for it. Today, plate boundary observatories (systems of GNSS receivers) can show it nearly in real time.

  8. Andrew Smedley says

    Marshall and Watson were right in the regard that H. pylori caused stomach ulcers, but the scientists who said stress caused ulcers were also partially right.

    Because stress suppresses the immune system, the gut microbiome is affected in such a way that the H. pylori are more likely to proliferate and cause ulcers.

  9. Darrell Steinbergson says

    I can’t believe such an anodyne speech would be objected to. I guess the mere use of the phrase “free speech” is now “problematic.”

  10. Jack B. Nimble says

    “……Left-wingers tend to be the most prominent Lysenkoists but the suppression of scientific opinions can occur in other contexts too…….”

    I’m old enough to remember when Robert Bork said, as part of his failed nomination to the US Supreme Court, that the 1st amendment to the US Constitution protects only political speech from government censorship, not scientific, literary or artistic speech. Conservatives seemed to be happy with this idea, both then and now.

    A brief visit to sites like will show that most of the attempts to stifle science in contemporary America come from the right wing, and it isn’t just climate science: evolution science and the soft sciences like sociology and anthropology have also been attacked by conservative politicians and pundits.

    In a few cases, like anti-vaxxers and advocates of natural or spiritual healing, right wingers join with left wingers to criticize mainstream science. These ideas, like those of the original T. Lysenko, are populist, anti-elitist ideas that deserve to be marginalized.

    Other criticisms of mainstream science emanate mostly from the left wing: attacks on GMO-foods and animal-based testing and research, for example.

    In terms of political power in the US, left wing critics of science are marginalized (except possibly in California), whereas right wing critics of science can and do hold high national office (Lamar Smith in Congress, the late A. Scalia on the Supreme Court and Scott Pruitt and Rick Perry in the Cabinet). That’s the important point to remember.

    • ADM64 says

      Bork did not enjoy unlimited support on the right. His views were grossly misrepresented by the left, however on the right he was criticized as a legal positivist who rejected any over arching principles behind the constitution.

      Scalia was not anti-science either.

      Scott Pruitt is not remotely anti-science. He has. Introduced requirements for transparency and peer review and publication of data and reproducibility of results at the EPA that have been lacking.

      What you’re doing is smearing critics of poor or politicized science as critics of science. Not the same thing at all. And the evidence for this is that whenever anyone challenges orthodoxy on climate, IQ, gender, race etc their arguments are never refuted, they’re attacked as bigots. Michael Mann’s lawsuit against his critics is of a similar vein.

      • Jack B. Nimble says

        About Scalia, one of his OWN law clerks said recently that ‘……..Antonin Scalia generally detested science. It threatened everything he believed in. He refused to join a recent Supreme Court opinion about DNA testing because it presented the details of textbook molecular biology as fact….’

        In other words, because Scalia couldn’t see DNA with his own eyes, he refused to believe that it exists. Scalia was the one being bossy and self-important, not the scientists!

        About Pruitt, he ‘…. has recently said that global warming may in fact benefit humanity. He says it’s “arrogant” to claim that humans know the ideal surface temperature for the planet in 2100, which is when scientists say some parts of the world will see catastrophic changes. Since taking the helm at EPA about a year ago, he has focused on scaling back climate science at the agency, which has removed hundreds of webpages related to climate change. He has also remade the agency’s Science Advisory Board, making way for more industry-connected researchers to influence policy.

        Opponents say it’s part of a long-standing pattern of Pruitt taking aim at established research to advance scientifically disproved theories that fit his political goals.

        They point to controversial bills Pruitt backed as a state senator representing Broken Arrow in the Oklahoma Legislature. He pushed legislation that would have required abortion doctors to tell patients that abortions could elevate breast cancer risks. He also called evolution “a scientific theory, not a scientific fact,” and supported a bill that would have allowed teachers to instruct children that evolution is merely a theory……..’

        Pruitt’s game with climate science is something like this: He claims that academic researchers with government grants can’t give objective advice on federal advisory boards because they have conflicts of interest, so he kicks them off in favor of industry researchers who don’t need grants [because their fossil-fuel employers fund their research]. Apparently a scientist who works for Exxon, etc., can’t have a conflict of interest about climate science. Pruitt also gives equal time to discredited or extreme-minority positions, like the idea cited above that abortions cause cancer.

        BTW, I should also have cited VP Pence as a young-earth creationist, and there are many other examples of science-deniers in high positions throughout the federal government.

        • scott allen says

          Scalia opposition to DNA was well founded, the collection of DNA has lead to many false conviction due to the recently discovered idea of trace DNA. Which basically all police forensic technicians can now discover your DNA in places and situation that you have never been in or around, this is caused by casual contact even thru the money that you use to pay your bills.
          Scott Puritt’s purging of the science advisor board is more then justified thru the many conflict of interest that those on the panel had, would you want a panel of doctors who took drug company money to make decision on what medication to recommend. His call for transparency in the research used to make policy for the EPA makes total sense, researcher who don’t p hack and are honest should not be hiding their methods and data, but should be proud of their accomplishments.
          “If we are not able to ask skeptical questions, to interrogate those that tell us that something is true, to be skeptical of those in authority, then we’re up for grabs for the next charlatan, political or religion who comes ambling along.”
          – Carl Sagan

    • Burlats de Montaigne says

      “most of the attempts to stifle science in contemporary America come from the right wing,”

      There is also a strong suspicion of science, the scientific method and empirical evidence/data from the left as well. Have a look at this Pinker speech.

  11. TomatoJuice says

    Being wrong is embarrassing. Having built your identify on a false premise is inadmissible.

  12. Scott says

    It’s interesting to me you would pick creationism as an example of undue persecution, or the teaching of it in schools as an example of “unscientific” thought. While it’s certainly true creationism isn’t falsifiable and so shouldn’t be considered a scientific theory, it’s also true science has been unable to create life, which to date falsifies the theory of “natural” creation (that would be creation not undertaken by intelligent design).

    Furthermore, should there ever be an example of artificial life, it would in fact support the theory of intelligent design, not falsify it.

    Quite the conundrum isn’t it?

    • Bill says

      I loved how you used the term natural creation. Too many believe that natural selection and creationism are in opposition without realizing they each describe different temporal periods. Natural selection and creationism hypothetically co-exist since we do not have any non-falsifiable theory on what provided the starting point for natural selection.

  13. Cjones1 says

    Galileo lost his patrons, one of them being the Pope, after satirizing them and, as a result, his scientific opponents gained enough religious/political backing to gain acceptance of their position.
    A priest, George LeMaitre, proposed the moment of singularity, was ridiculed, and his proposal was labeled the Big Bang Theory by his opponents.
    As far as the AGW hypothesis, water vapor accounts for 95% of the greenhouse gases, but is mostly ignored by the CO2 enthusiasts – as are the cyclical trends of the Sun and Earth of the past. Fortunately there are enough voices familiar with the limited data concerning Earth’s climatic history and new data that also reveals changes due to extraordinary events related to tectonics and/or bolide impacts.
    We can not allow dissenting voices to be silenced or we may well be silenced by the Lysenko types who preached Marxist-Leninists as a science once upon a time.

  14. Tim Regalado says

    Killer quotes by Planck and Feynman. Great article!

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  19. Mussie says

    It is good reading. I benefited a lot out of it. Yet, the cuases could have been analyzed well. For example, I don’t think that the mere stuborn nature of scientists could be a mere reason for the rejection of new findings. I believe the underlying reasons are very important and vital. For example, inability or unwillingness to perform structural adjustment cost to fit to a new finding, fear of loss of social/job security, or benefits or reputations, threat of dismantling the established knowledge and its institutions and others.

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