

In 1919, a total eclipse of the sun provided a rare opportunity to test Einstein’s theory of general relativity. Arthur Eddington, a British astronomer and admirer of Einstein who had resisted the nationalist hatreds of the First World War, sent two teams to the mid-Atlantic to observe Mercury during the eclipse, and test the German scientist’s theory. To the astonishment of his colleagues, and the world, Einstein was vindicated. Two centuries of orthodoxy in physics were disrupted overnight, and Einstein was catapulted into a celebrity that has never left him.

At that time much of Europe was in chaos. The Austrian and Russian Empires had collapsed under the strain of the First World War, and Marxist revolutionaries rushed to fill the void. They called for socialism in stirring public speeches, raised militias, staged coups and counter-coups, and fought their nationalist enemies in the streets and on the battlefield. Amid this struggle all eyes turned to the Soviet Union, whose confident leader, Lenin, preached the dawn of a new era of happiness and progress. He was certain that Karl Marx had discovered a science of history, and that it was at last possible for humankind to seize control of its destiny, completely transform society—even to predict the future.

Karl Popper, soon to be one of the most famous philosophers of the twentieth century, was a student in Vienna during these troubled but exhilarating times. He had been mightily impressed by Einstein and Marx. Both could muster impressive arguments, presented themselves as authentically scientific, and proposed revolutionary new ways of looking at the world. But the more he thought about it, the more dissatisfied he became with Marx, and the more he admired Einstein. In The Logic of Scientific Discovery (1934), he argued that the difference between authentic science and pseudo-science was falsifiability. Einstein had put his theory to the test. He had made definite predictions, and if they had proven incorrect, that would have been evidence against his theory. While no theory can be completely proven or disproven on the basis of just a handful of observations, prediction was a crucial test. Anyone could make claims, but prediction forced the issue in an unambiguous way. So, Popper concluded, the more predictions a theory makes, and the more risky they are, the more genuinely scientific it is. The more Einstein’s theory was tested, the better it looked.

Marx, too, had made predictions. He had predicted that the revolution would occur first in Germany, since it was the most heavily industrialized; he had predicted that depressions would become more and more severe over time as the capitalists failed to find buyers for their over-produced goods; and he had predicted that the workers would become more and more miserable as the owners slashed their wages in an attempt to make up the shortfall. None of these predictions had been borne out, yet Marxists were more numerous, more deeply convinced, and more powerful than ever. What was happening?

The key, Popper believed, was the word “science,” for it carried then, as it does now, tremendous prestige. To speak it is to invoke the awesome technological progress of the last few centuries, the principled stand of Galileo, the towering genius of Newton and Darwin, and, in short, our highest aspirations to truth and reason. But as astute observers recognize its deep emotional resonance, they will try to claim it for all sorts of purposes—politics, ethics, ideology, beliefs about the meaning of life and our place in the cosmos, and an entire philosophy of life, can all be called science. While there is no reason, in principle, that these views cannot be scientific, they usually do not make the type of predictions that characterized Einstein’s physics. Yet people who feel they have something important to say are naturally tempted to call their ideas scientific, hoping that some of the prestige of Newton, Darwin, or Einstein will rub off. In the never-ending war of ideas, invoking the symbolism of science can provide a powerful advantage.

Einstein took a risk. So, too, did Marx. According to Popper they were both scientific in that sense, but Einstein passed the test of prediction where Marx did not. So, to continue to hold to Marxism after its predictions had failed was not scientific, but ideological, and this was the reason that no amount of evidence or argument could shake a convinced Marxist. In order to protect science from ideological abuse, Popper argued, we need to keep this distinction in mind. Genuine science takes risks, and its products could be disproven. Ideology, by contrast, risks nothing, and is never wrong.

Popper published these views under the shadow of a National Socialist takeover of Austria. He fled his country shortly after he published, and ended up in New Zealand for most of the Second World War, where he wrote a classic defense of liberalism called The Open Society and Its Enemies (1945). He argued that the Open Society—the liberal, tolerant society, which permits dissent and is based on democratic institutions and values—has always faced opposition from within, even from intellectuals. Because it leaves questions of meaning and identity to the individual, rather than to the group, it also leave individuals to fend for themselves when it comes to the most important questions they can ask about life. No one can tell us what to believe about ethics, politics, religion, science, the meaning of life, or any of the other profoundly important questions we seek answers to. We have to decide for ourselves, on the basis of reason and evidence, and that is not only a freedom, but a responsibility.

There have always been people who find that responsibility a burden, and who wanted to rid themselves of it. Others have been only too happy to take it away. Provided that the appropriate symbols were invoked, through gestures, phrases, and rituals, these people can get along nicely. In that sense it hardly matters what the phrases and gestures actually are, or where they come from. They could be the symbols of nationalism or universalism, hope for the future or veneration of the past, of religion or science, or indeed anything else. What matters is not the symbol, but the actions that follow from it, and in that sense the end result of this irresponsibility is always the same—the demand for a closed society, where all the answers are already known, where dissent is not permitted, and where there is no greater crime than disloyalty to the group.

In Popper’s time the enemies of the open society were Communists and Fascists, who, however much they hated each other, agreed in their rejection of democracy. But he stressed that this was not a one-time affair. The open society always had enemies, and always would. In the time of the Greeks those enemies were the Platonists. They demanded the rule of an all-knowing philosopher king, whose knowledge of the invisible Forms and Essences would lift him high above the people, and whose Guardians would ruthlessly punish dissent, in order to create a utopia. In the time of the Enlightenment those enemies were the Hegelians. They rejected democracy in favor of monarchism, smothered rational inquiry beneath the fog of romanticism, and dreamed of a return to the Middle Ages. In our own time Christian, Jewish, and Islamic fundamentalists similarly reject the open society. Christian fundamentalists want Six-Day Creationism taught in public schools instead of genuine science, they reject the right of gay people to adopt or marry, and are promising to build a huge and ridiculous wall on the Mexican border to keep out immigrants. Jewish Fundamentalists claim that Palestine is their holy land, promised to them by God, and gather in the streets of their cities shouting “Death to the Arabs!” while their tanks and fighter jets make their wishes a reality. And as we all know, Islamic Fundamentalists have launched dozens of attacks in their own countries and in ours—in New York, Paris, Mumbai, Beirut, Cairo, and many other places, have cruelly tortured prisoners, and terrified millions of people across the world. When asked about their goals, they say they want to destroy the mutual understanding that makes it possible for Muslims and other communities to live in peace—a strategy that is likely to succeed if we do not defend our values as well as our lives from their terror campaign.

While all the world’s attention is focused on religious fundamentalism, there is a new tribalism, and a new revolt against reason, taking shape within liberalism. The name of this movement is New Atheism, but it would be more appropriate to call it Atheist Fundamentalism. Like their religious counterparts, these people believe they are members of a select and blessed minority—a Chosen People—and that they possess an infallible truth, called science. Science, they say, can answer every question simply and convincingly, whether it’s about ethics, politics, the existence of God, the meaning of life, or our place in the cosmos. There are no genuine philosophical problems, no real moral dilemmas, no mysteries, and indeed not much reason to have these discussions at all. Science has spoken: your job, if you are truly rational, is to submit, and the proof of your rationality is your submission. They are terrified of much the same prospect as their Christian, Jewish, and Islamic Fundamentalist counterparts—of sharing space with people whose ideas they detest.

Atheist Fundamentalists talk about science quite a bit, but it seems to me that Popper, who understood only too well how much was at stake in our use of that word, would have rejected them as narrow-minded ideologues. What bold, falsifiable predictions have they made? What are they really risking when they reclassify their political and philosophical opinions as science? Do their arguments really show the spirit of critical inquiry that they are always praising? Are their views genuinely scientific, or are they simply appeals to prejudice? Do they want more freedom, or less? Can they honestly claim to represent the values of science, or the open society?

To me, science means, above all, a spirit of open-ended, critical inquiry. It means appeals to evidence rather than to prejudice, and to reason rather than to fear. To me, liberalism means the plurality of a free society welded together by humanism, and that we should value and respect all human life, simply because it is human. It means that we hold people accountable for what they do, not for who they are or what they believe. When I read people argue, on the basis of science and liberalism, that we have no right to think matters through for ourselves, or that we should hate, fear, and despise people who do not share our opinions, I have to wonder what they think the words “science” and “liberalism” mean.

Fundamentalist Atheists aren’t the kind of allies we need in the struggle for reason and tolerance, for reasons Karl Popper saw only too well. Like that friend who you used to have good times with, but these days only brings you down, they aren't actually friends at all. They’re frenemies, and it’s time to cut them loose.

Daniel Halverson is a graduate student studying the History of Science and Technology of nineteenth-century Germany. He is also a regular contributor to the PEL Facebook page, where this article appeared previously.