The Limits of Science: Debating "Denialism"

Last time we saw one problem with having an exaggerated sense of the objectivity and purity of science. Another has to do with how many scientists and non-scientists (mostly self-proclaimed rationalists) deal with people who disagree with them over one theory or another. This view seems to be epitomized by Michael Specter is his book Denialism.

I haven't read the book, and don't plan to, but I read the introduction and I think that was enough to get a flavor of the book. I'll sum it up for you: if you don't love science as much as I do and disagree with scientists on anything than you are obviously stupid and irrational and should be sterilized. And your children should be kidnapped.

Attitudes like this drive me nuts for several reasons. One, scientists themselves disagree about a great many things in science. There are equally "scientific" papers that argue for either the primacy of astronomical causes (e.g. orbital changes) or terrestrial causes (e.g. greenhouse gases) of past climate change. There is disagreement over the composition and source of the early Earth's atmosphere. Or, think about how many times we've heard things like chocolate is good for you, wait it's bad for you, oops now it's good for you again. There is simply no such thing as "science says this about something and that's the end of it." Within the scientific community there exists a myriad of viewpoints, theories, and interpretations of facts relating to just about any scientific topic. To adopt one particular theory and dismiss everyone else as being part of "denialism" seems to be a bit of a stretch.

Secondly, philosophers of science as well as scientists themselves often write about how science will never truly end, about how there is always more to discover, and that this fact is partly why science is so exciting. Nicholas Rescher lays out rigorous philosophical arguments for this idea in his excellent book Nature and Understanding, and this was also the main topic in a recent editorial in the journal Science. Though frequently acknowledged, many people fail to appreciate what this means for any particular scientific theory: it is subject to revision and/or complete reworking.

A brief look at the history of science reveals the same story over and over again. Proponents of one particular theory demonize, ridicule, or ignore their opponents for daring to question established wisdom. Consider Ptolemy's geocentric universe, Wegener's theory of continental drift, or Newton's theory of gravity. Wegener was ridiculed viciously for his "wild" ideas by the geological community, yet now the fact that continents have moved over time has become the new established wisdom. There isn't any reason to think that we are so special as to be immune to this sort of thing. Our scientific theories are also under constant revision and scrutiny. It is ironic that self-proclaimed rationalists end up speaking of particular scientific theories in the same way others might speak of an unquestionable religious dogma.

Dreaming up some perjorative labels for people who disagree with you is not new. Mike Specter just adds "denialism" to the vocabulary of people who want a way to pat themselves on the back for being right while being comforted by the fact that all those other people who disagree with them are so obviously stupid and irrational. It's not that people can't be irrational. They can be, and many people are. But Specter's particular approach to this problem strikes me as profoundly unhelpful, anti-intellectual, and dare I say it, unscientific.

The Limits of Science: is science ever pure?

Philosophers of science have tried for over a century to establish a rigorous, logical foundation for science, one that justifies science as an objective source of knowledge. No obvious solution is forthcoming. Instead, historians and philosophers of science have come to realize that, despite the protests of self-proclaimed rationalists, science is not the ultimate, infallible source of knowledge we might like it to be.

In case some relativists out there are getting too excited, it is equally clear that science is not merely a social construct or a human invention that has no connection to an underlying reality. As mentioned in a previous post, the success of science is indisputable. Someone once said that thanks to modern science, an elementary school student now knows more about the world and the universe than Aristotle did. Science is a not a social construct, but it is a human enterprise that is influenced by everything that affects humans.

Examples of the influence of culture and ideology on science abound. Probably the most famous example is Darwin's particular theory of evolution by natural selection and sexual selection. Darwin's theory of individuals struggling to survive has an undeniable parallel to Victorian ideas about economic competition and societal progress. His ideas about sexual selection also came straight from his cultural view of men and women. Genetecist Rich Lewontin writes, "In reading Darwin's theory, one can see the proper young lady seated on her sofa while the swain on his knees before her begs for her hand, having already told her father how many hundreds a year he has in income."

Another example involves the religious and philosophical views of James Hutton and Charles Lyell. Together they are often regarded as having started the field of geology and are hailed for their "modern" scientific outlook. In fact, their views on the Earth were rooted in beliefs in Deism and an eternal Earth. This led to the formulation of "uniformitarianism," the idea that everything about the Earth (both in the past and now) can be explained by the sorts of slow, everyday processes that we currently see. This idea proved to be helpful in getting scientists to think correctly about many of the formations we see on the Earth (e.g. mountains, river valleys, etc.).

Uniformitarianism, though, being rooted ultimately in ideology also hindered science in some ways and was flat out wrong in others. The obvious problem is that the Earth is not eternal, and in fact has a history. It has not always been the same, and therefore not everything can be explained through the processes we see at work today. The existence of ice ages and the massive glacial erosion they can cause was at first denied by scientists who followed Hutton and Lyell's methodology. They insisted that "catastrophes" had no place in the science of geology. As we now know, unique, catastrophic events have played an important role in the history of the Earth. These include everything from the formation and cooling of the early Earth, to ice ages, to asteroid impacts. These phenomena were initially ruled out because science had been influenced by a preferred ideology.

This is not to say that the influence of ideology is always bad. After all, most scientists consider Darwin to have been right about a great many things and geology no doubt benefited from Hutton's insistence on paying attention to the slow processes happening around us. Acknowledging the influence of culture on science does not mean giving up on science. It simply means that we must pay close attention to be able to distinguish where the empirical claims end and the ideology begins. In other words, to be aware of the limits of science.

The Limits of Science

The success of science is indisputable. One only needs to look at modern medicine and technology for convincing evidence that science works. In the approximately 400 years since the birth of what we might recognize as modern science we have undoubtedly gained considerable knowledge of the natural world and its inner workings. In that time science has become a central part of our culture and, in many ways, has replaced religion as a major source of authority.

Since the Enlightenment there has been a steady trend of secularization in public life. Where once the Church wielded tremendous social and political power to uphold their own dogmas (e.g. the flat earth; just kidding, they actually never said that), some critics allege that the scientific establishment has in some ways taken the Church's place, forming a kind of scientific priesthood.

In fact, one famous proponent of science in the Victorian age and one of the first professional scientists, Thomas Huxley, had exactly that in mind. To Huxley and his supporters, science needed to replace religion as the supreme source of cultural authority. Historian Peter Bowler observes that the great museums of natural history built in Britain and America during the 1800s are rather cathedral-like (see the London museum above), and that this "helped confirm the role that science had usurped as the source of moral authority in the modern world."

Leaving aside the problem of "science" being a source of moral authority, what does this mean for us? One thing it means is that science's dominant position in our culture can cause people to accept pronouncements or conclusions uncritically. No doubt it was common in earlier centuries for people to uncritically accept what religious authorities told them, and we can have the same problem with scientific authorities now. In fact, in some ways it is probably worse today because science has become so specialized that it is sometimes hard for other scientists, nevermind lay people, to make sense of theories and concepts outside of their own fields.

As a former science educator, I am interested in helping people achieve science literacy, part of which includes being able to critically evaluate scientific claims and evidence as well as being aware of the nature and history of science. Over the next few weeks I intend to write further on these topics because while science is clearly an important source of knowledge, science (and especially scientists) are hardly infallible. Let's not accord to scientific theories the same blind faith and adherence to dogma that rationalists are so quick to criticize in our religious forebears.

Whose animals are more awesome? America's or Europe's?

I'm finally finishing Bill Bryson's A Short History of Nearly Everything (I started it a few years ago and for some reason stopped) and I am enjoying it very much. Intertwined in his popular tour of the history of science are interesting and sometimes hilarious anecdotes about the scientists under discussion.

During a discussion of the awkward rise of paleontology, Bryson writes about a surprising dispute between Europeans and Americans over the impressiveness of each continent's natural fauna. The great French naturalist Georges-Louis Leclerc, Comte de Buffon, writing about America, said that the animals and Native Americans were inferior in every way to those of Europe. According to Leclerc, North America was a country of stagnant water, sunless forests, and rotten swamps where the animals and even the Native Americans "lacked virility." "They have no beard or body hair, and no ardor for the female," and their reproductive organs were "small and feeble." Other Europeans joined in the attack, one writing that Native American males were so feminine that they had "milk in their breasts."

Thomas Jefferson was furious with this description and sent a general and some soldiers into New Hampshire to capture a bull moose to send to Leclerc as, in Bryson's words, "proof of the stature and majesty of American quadrupeds." Unfortunately, the moose they brought back didn't have horns big enough for Jefferson's liking, but the general had also included a large rack of antlers from an elk for Jefferson to attach if he would like. Apparently they figured no one in France would know the difference anyway.

At around the same time, other Americans were unearthing "the great American incognitum," a huge creature that would only later be identified as a mastodon (oddly, a Frenchman named Cuvier would be the first to formally describe and name it; even more oddly, mastodon means "nipple-teeth"). I'll let Bryson tell the story:

"In their keenness to demonstrate the incognitum's bulk and ferocity, the American naturalists appear to have become slightly carried away. They overestimated its size by a factor of six and gave it frightening claws, which in fact came from a Megalonyx, or giant ground sloth, found nearby. Rather remarkably, they persuaded themselves that the animal had enjoyed "the agility and ferocity of the tiger," and portrayed it in illustrations as pouncing with feline grace onto prey from boulders. When tusks were discovered, they were forced into the animal's head in any number of inventive ways. One restorer screwed the tusks in upside down, like the fangs of a saber-toothed cat, which gave it a satisfyingly aggressive aspect. Another arranged the tusks so that they curved backwards on the engaging theory that the creature had been aquatic and had used them to anchor itself to trees while dozing."

Unfortunately, Leclerc was not impressed. He insisted that the most telling feature of this animal is that it was extinct, "proof of its incontestably degenerate nature."

The Da Vinci Code

I just watched the last part of the movie The Da Vinci Code on TV. I watched it in the theater back when it first came out to see what all the fuss was about. It was OK as a movie: not terrible, not great. As history, though, it's kind of silly. I really can't believe that people take this book so seriously. Christians often get criticized for having "faith" in ancient texts, which may or may not be true or accurate. But a novel from some guy in New Hampshire happens to contain all these previously unknown secrets of history? Is this plausible?

There is no evidence that Jesus had an intimate relationship (nevermind children) with Mary Magdalene. I heard an interview with a scholar on NPR back when the movie was first out, and he discussed the texts which people suggest describes Jesus and Mary kissing, an indication of a physical relationship. The problem is that the texts are incomplete: many or most of the words are actually not there. The scholar quoted the sections in question. It was something like: ...and they were on their way..........from.......over to...........Galilee......Jesus.......lunch.....walking near the.....and then........Mary.......Jerusalem.....in between the........kissed.....returned from...etc etc. I'm obviously being facetious here, but it was something like that. The speculative leap from text like that to Jesus and Mary were lovers and had children is so large that, again, I find it hard to believe that people take this stuff seriously. The scholar said that there is no textual evidence for this stuff; people routinely kissed as a greeting back then, and Jesus and Mary were not the only ones mentioned in the text.

The assertion that Mary was in Da Vinci's painting of The Last Supper is also problematic. The painting is of Jesus and his disciples. There were twelve of them. If Mary is in there, John, a disciple, is not. I'm no art historian, but don't you think someone would have noticed if a disciple was missing before now? John, the disciple that is claimed to actually be Mary, is portrayed as feminine, and this is supposed to be evidence that it is a female. The problem: the character is wearing male clothing and it was not uncommon at the time (or in other works of Leonardo) for a subservient male to be portrayed as feminine. John's femininity is suppose to imply his lower status (compared to Jesus)and love for Jesus. The evidence for Mary being in the painting is therefore thin. Besides, are we really supposed to believe that Dan Brown (or the book he got this idea from, Holy Blood, Holy Grail) uncovered this secret that scholars have missed for the last 500 years?

Among other things, the movie stated that Newton was persecuted by the church. This is completely false. Newton was the leading man of one of the most conservative universities. He was a firm believer in God and believed his scientific work was uncovering the secrets God had used to create the universe. He also wrote extensively on theological matters (more than he did on science, actually).

The movie also laughably stated something along the lines of...did you ever wonder why the most talked about object in Christianity, the holy grail, is missing from Da Vinci's painting? The "holy grail" is never mentioned in the Bible, and I have never heard any Christian talk about it. It was probably an invention of some church in the Middle Ages who wanted a relic to draw pilgrims.

Anyway, if nothing else, The Da Vinci Code is an interesting example of peoples' propensity to believe nonsense as long as it somehow challenges orthodox views within Christianity.

The Rise of Modern Geology

In most modern texts the credit for the development of modern geology goes to folks like James Hutton and Charles Lyell. Perhaps the term "uniformitarianism" rings a bell, describing the approach that "the present is the key to the past." In other words, all geologic phenomena, past and present, can be described by the same processes we see today acting over long periods of time. Earth's history is therefore uniform and accessible to scientists today. Proponents of the other historical tradition , the catastrophists of the 17th, 18th, and 19th centuries, are dismissed as religiously motivated quacks. Their theories only retarded science, while Hutton and Lyell paved the way for our modern understanding of the Earth. Historians have shown this common narrative to be yet another myth (see here or here) concerning science and religion.

This time, Charles Lyell in the 19th century and C.G. Gillespies in the 20th may be blamed in part for perpetrating this myth. Lyell, in his Principles of Geology, spent some time in the introduction framing the catastrophists as religious folk whose theories were based on religious bias and miracles rather than scientific evidence. Gillespies in his 1951 book Genesis and Geology set up the narrative describing certain early geologists (Hutton and Lyell) as the true founders of the discipline while ignoring the contributions of others. Catastrophists were portrayed as religious and as only impeding science by, among other things, sticking to a Biblical time scale and invoking supernatural events like Noah's flood.

The truth, of course, is more complicated. In an attempt to keep this short, I will bullet the main points:

• First, it is true that 17th century Protestants argued for a young Earth and influenced the study of natural history in a way that did not exactly parallel our modern approach. However, the priests and theologians were studying natural history and were certainly a major part of the tradition which led to our modern approach.
• Some catastrophists were Christians; others were not. Many made significant contributions to geology. Most were not concerned with the exact age of the Earth at all.
  
• Those catastrophists who did argue for a natural history more in line with scripture were British; in other words, this was an isolated phenomena, not representative of the tradition as a whole.
• Neptunism, a movement within catastrophism which invoked water and floods to explain geologic phenomena often had nothing to do with supernatural events like Noah's flood. Most catastrophists, Christian or otherwise, were perfectly content invoking natural events to explain natural history.
  
• Catastrophists like Cuvier, Hooker, Humbolt, Sedgwick, Murchison, Werner, and de Maillet all made contributions to modern geology, including the understanding that the Earth's crust is made of ordered layers of rocks (the stratigraphical sequence). The importance of this cannot be overestimated.
• George Cuvier was an eminent paleontologist and catastrophist who established the fact that extinction events had occurred on Earth through catastrophes, not the slow everyday processes of Hutton and Lyell.
• Hutton and Lyell, far from being paragons of objectivity, were influenced heavily by their own religious beliefs. They were deists.
• In their theories, the Earth was eternal and ahistorical. This is a direct result of their religious beliefs and is in flat-out contradiction with our modern understanding of the Earth.
• The catastrophists got it right; our Earth had a beginning and has had major, different historical periods. The Earth and its history is not as "uniform" as Hutton and Lyell would have liked.
• Catastrophists believed that the Earth was hotter back when it formed and therefore geologic processes like earthquakes and volcanoes have differed throughout geologic time. They were right. We now know that the Earth was originally molten and has been cooling ever since.
• In short, our modern understanding is a combination of uniformitarian and catastrophist theory. Our Earth is shaped both by slow, everyday processes like weathering, erosion, movement of tectonic plates, and by catastrophic, historical events like the original formation and cooling of the Earth, extinctions, ice ages, and asteroid impacts.
  

This myth is illustrative of the ambition of people who would like to rewrite history in favor of a chosen few scientists whose taste in worldview more closely mirrors their own. Even non-religious scientists get lumped in with the religious ones and dismissed if they don't fit the desired narrative.

The Flat Earth Myth

One of the great modern day myths surrounding science and religion involves Christopher Columbus and a flat Earth. Most of us were taught in school that Columbus wanted to travel the world despite all the dire warnings about falling off the edge of a flat Earth. He bravely set sail anyway and changed the world through his discoveries, or so the story goes. Many of us were taught in school that throughout the early and late Middle Ages most people thought that the world was flat. In addition, we are told that this state of affairs was the result of the oppressive religious authorities of the time. 

The truth, however, is that the West has known the Earth was a sphere since at least the 4^th century B.C., when Greek philosophers like Pythagoras followed by Aristotle and Ptolemy all laid out arguments for a spherical Earth (a few, like Eratosthenes, even took a shot at calculating its circumference). This knowledge survived into the Middle Ages, and virtually all educated people and scholars still affirmed a round Earth. Columbus and company all believed the Earth was round; no one warned him about falling off any edge. He was warned about his faulty calculations, which led him to believe that the Earth was much smaller, and India much closer, than it really was. As we all know, he ended up in North America instead.

So how did we end up believing this fable about Columbus and the rest of Medieval Europe? Historians have traced this flat Earth myth to the 19^th century. One of the first appearances was in the early 19^th century in Washington Irving’s fictional account of the Columbus story, and sometimes Irving is given most of the credit for the flat Earth myth. However, recent scholarship shows that the myth became a staple in textbooks in the late 19^th century after the publication of two books by John Draper and Andrew White. These men were overzealous secularists who wrote distorted (but highly influential) histories of science. Their intent was to provide a narrative involving science and religion where science is struggling for truth and progress and religion is doing its best to hamper scientific advances. The flat Earth myth was one pillar in their overall thesis: religious superstition is always trying to snuff out scientific progress. 

How exactly did Draper and White convince us that Medieval peoples believed in a flat Earth? They found two minor figures (no others have been found), Lactantius (245-325 A.D.),  a North African writer, and Cosmas Indicopleustes (fl. 540 A.D.), a Christian merchant from Europe, that wrote in support of a flat Earth and made this minority opinion appear to be the norm from the Dark Ages and onward. In fact, from the patristic period to the late Middle Ages (i.e. whenever you look), all church scholars, ranging from the Venerable Bede to Augustine to Aquinas, affirmed a spherical Earth.

Historians of science have dismissed Draper and White’s books as sloppy, selective scholarship that ignores the bulk of the historical data. Unfortunately, the myth persists. When I was teaching, I would ask my students each year if they had been taught the Columbus myth, and each year at least half of the hands were raised (I suspect most of the rest had also been taught it, but had forgotten). This is kind of sad. Here we are in the 21^st century believing that people in the Dark and Middle Ages were fooled by religious authorities into believing in a flat Earth, when in fact we are the ones clinging to a discredited myth.

Further Reading: 

Stephen J. Gould's essays Dinosaur in a Haystack 

Science & Religion: A Historical Introduction

Inventing the Flat Earth