Friday, February 14, 2014

The Abyss of Time: When Genesis Met Geology

In the beginning when God created the heavens and the earth, the earth was a formless void and darkness covered the face of the deep, while a wind from God swept over the face of the waters. Then God said, “Let there be light”; and there was light. And God saw that the light was good; and God separated the light from the darkness. God called the light Day, and the darkness he called Night. And there was evening and there was morning, the first day.                                                                   
Genesis 1:1-5 (New Revised Standard Version)
So begins the Bible--probably the most influential book in human history. As its famous first lines declare, the Bible begins at the very beginning, with the creation of the universe by a single, all-powerful God. It's an impressive start--those are some of the most stirring and powerful words ever written. The Genesis creation story has given meaning to people's lives for millennia by telling them how the world began and where they fit into it. It tells believers that humans are God's special creation, placed at the center of the universe and charged with dominion over the rest of the earth. But it also tells them how we fell from grace, after Adam and Eve ate of the tree of knowledge of good and evil. That's when they and all their descendents were driven from Eden, and when toil, suffering, strife, and death came into the world. A dangerous thing, knowledge.

The Deluge / Gustave DorĂ©
Until a couple hundred years ago, there was little reason to think the Genesis creation story wasn't basically true. It seemed as plausible as any other account. It also had the advantage of being epic and awe-inspiring while giving people answers to very big questions--not just factual questions like "where do we come from?" but questions of meaning and morality as well: Why are we here? Why is there evil and pain? How should we live? What role do we play in this creation? 

As compelling as the Genesis account is, there have always been those who thought it shouldn't be seen as completely, literally true. St. Augustine, for example, didn't think the Genesis creation story was the last word on factual knowledge of the natural world, and cautioned other believers against insisting that it was. As he wrote in The Literal Meaning of Genesis:
It not infrequently happens that something about the earth, about the sky, about other elements of this world, about the motion and rotation or even the magnitude and distances of the stars, about definite eclipses of the sun and moon, about the passage of years and seasons, about the nature of animals, of fruits, of stones, and of other such things, may be known with the greatest certainty by reasoning or by experience, even by one who is not a Christian. It is too disgraceful and ruinous, though, and greatly to be avoided, that he [the non-Christian] should hear a Christian speaking so idiotically on these matters, and as if in accord with Christian writings, that he might say that he could scarcely keep from laughing when he saw how totally in error they are. In view of this and in keeping it in mind constantly while dealing with the book of Genesis, I have, insofar as I was able, explained in detail and set forth for consideration the meanings of obscure passages, taking care not to affirm rashly some one meaning to the prejudice of another and perhaps better explanation.
Like many other Christian and Jewish scholars through the ages, Augustine believed Genesis was intended as a spiritual work, not a scientific one. He thought many passages should be read allegorically, with an eye to what they say about our relation to the creator, instead of the exact features of his creation.

Still, even subtle thinkers like Augustine had little reason to think the creation account wasn't literally true in broad outline: that the world was a few thousand years old, for example, or that a great flood had shaped the world we see today. No compelling alternative existed for over 1000 years after Augustine.

Siccar Point / Photo by Anne Burgess
The first to start thinking in new directions were geologists, but their change of view took time. In the 1600's, Nicolas Steno, whose stratigraphic principles are still fundamental to geology today, believed that in tracing the history of rocks he was tracing the results of Noah's flood. In the late 1700's, however, James Hutton proposed that the landscapes around us weren't formed all at once, but gradually, by the same processes we see around us today--erosion by wind and water, deposition of sediments by rivers, the shaping of sand dunes by the wind, and so on. At a rock outcrop in Scotland called Siccar Point, Hutton noted that dramatically tilted layers of sedimentary rocks were overlain by flat layers of a different sedimentary rock. Pondering how this came to be, he started to understand the true depths of earth history. The first layer, he reasoned, had been deposited horizontally in an ancient sea and solidified into rock. How long this took, Hutton didn't know, but it was a lot longer than a few thousand years. And that was just the beginning. These rocks were then uplifted and tilted by powerful (but slow) geologic forces, worn down again by erosion, and then covered by another sea, where a new layer of rocks formed on top of them. If all this had occurred at the same rates we see today, the length of time required would be almost unimaginable--not thousands of years, but millions, or hundreds of millions. Hutton's friend John Playfair, who visited the same spot with him, later wrote, "the mind seemed to grow giddy by looking so far into the abyss of time."

Despite Hutton's dizzying insight, most geologists of the day kept seeing the landscape as having been shaped by the great deluge. By the 1830's, however, most of them had realized the model wasn't tenable. The curved valleys and far-flung deposits of gravel and boulders found in northern Europe turned out to have been deposited by ice, not water. As for the rock strata and the fossils they contained, they were too uniform and well-organized to have been deposited by a flood. A great flood would have scrambled all the sediments together, not stacked them into layers with distinctive fossils that changed regularly from the bottom to the top of the stack. The flood model just didn't add up. That's why, two decades before Darwin published his theory of evolution, geologists had rejected the idea that the earth was created in a literal six days a few thousand years ago, and then shaped by a worldwide flood. Many of these geologists were devout Christians, but they were also scientists dedicated to the idea that evidence trumps theory, not vice versa. The evidence in the rocks pointed to a very different story than the one Genesis told.

Whether or not the Genesis creation story was true in an allegorical or spiritual sense, scientists had shown that it was not true in a literal sense. It wasn't science or history--it was mythology. In fact, later in the 1800's scholars found that it was based on even older myths from Mesopotamian civilizations that long pre-dated Hebrew society. These stories featured a worldwide flood and a hero saving his fellow beings by putting them in a boat, and like Noah, they even sent out birds to see if the flood waters were receding.

Scholarly opinion had moved on from the literal view of creation, and most educated Christians moved on with it. They didn't necessarily believe in evolution, at least evolution without God's guidance, but most of them did accept that the earth was incredibly ancient. Young Earth Creationism (YEC) of the type that exists today got its start in the early 20th century, when a Seventh Day Adventist named George McCready Price began publishing books attacking mainstream geology. His first book was actually called Illogical Geology. McCready's torch was taken up by John Whitcomb and Henry Morris in their 1961 book The Genesis Flood, which insisted that the stratigraphic record of rocks and fossils was laid down by the flood. Fossils, they said, were bones of the animals killed by the flood. Scientist's claims that those fossils changed in a systematic way over time were simply nonsense--lies and wishful thinking.

Generally, modern creationists have explained changes in fossils from lower to higher in the geologic column with three different hypotheses. The first is that such vertical sorting might be caused by the different hydrodynamic properties of organisms. Some would sink to lower strata, while the more buoyant or less streamlined ones stay in the upper layers. Then there's the idea that organisms have differing success in running toward the high ground. Humans got farther up the hillsides than tortoises before the waters caught them (Lowland plants found only in the uppers layers are clearly a problem for this idea). Finally, creationists have argued that different strata, with their characteristic assemblages of fossils, represent ecosystems from different parts of the earth, transported and then neatly stacked by the flood waters.

Young Earth Creationism got more popular after Whitcomb and Morris's book, and it remains popular today, especially in the United States. According to a Gallup poll in 2012, 46% of Americans agreed that, "God created human beings in pretty much their present form at one time within the last 10,000 years or so." Organizations like the Institute for Creation Research and Answers in Genesis, which runs the famous Creation Museum in Kentucky, are very influential among evangelical Christians, and have big, well-designed websites. The creationist presence on the web is huge and misleading. If you do a Google search for topics related to evolution, geology, or even cosmology, as many as half the links that come up promote creationism. This is in spite of the fact that only 2% of working scientists believe that "Humans and other living things have existed in their present form since the beginning of time."

Not only is sudden creation/young earth creationism rejected by the vast majority of scientists, it differs from the mainstream view by orders of magnitude. The scientific consensus is that the Earth is 4.6 billion years old. That means people who believe the earth is 10,000 years old or less think the Earth is 460 thousand times younger than scientists do. If the scientists are right, then as the physicist Lawrence Krause pointed out, the creationists are making as big a mistake as if they believed the United States were 17 feet across. Put another way, it's like mainstream scientists and young earth creationsts are arguing over whether the Empire State Building is 1250 feet high or less than half an inch. Not only that, but if the YEC people are right, then it's not just the theory of evolution that in trouble. Fundamental principles in all the sciences, including physics, astronomy, chemistry, geology, biology, and anthropology, would have to be abandoned. We're not talking about trivial differences of opinion here. Somebody is wrong, and wrong in a very big way.

But who? Obviously, anyone who follows this blog knows I'm going to side with 98% of scientists over 46% of the general public. Modern creationists have revived a view that was long ago tested and rejected by geologists. I think that's one of the best, and least appreciated, arguments against creationism: scientists already rejected it long ago, and not because they had some kind of atheist agenda, but because the evidence just didn't support it. In fact, most of them were Christians who initually believed in the literal creation story, and fully expected the rocks to support that story. When it didn't, like good scientists they abandoned that hypothesis, though sometimes with great reluctance.

Another way of putting this is that if the young earth/Noah's flood view had been correct, things would have gone in exactly the opposite direction by now. Scientists from around the world, Christian and otherwise, would have been convinced by multiple lines of converging evidence that the earth is young and was shaped by the flood. Many old-earthers would have held out, sometimes for decades, but eventually they would either have had to accept the young earth and flood theory or stop claiming to base their views on the data. But that's not what's happened. What happened was just the reverse. The rocks said what they said, and scientists accepted the testimony of nature over preconceived ideas, because that's how science works. That's what science is.

That's one reason faith-based creationism can't be a science, and shouldn't be taught in science class, no matter what the "creation scientists" claim. In science, evidence always trumps ideology--perhaps not immediately, but eventually. With creationism, it's the other way around--ideology trumps evidence. Most creationists admit that they see scripture, not empirical evidence, as the ultimate authority on what is true. They start by assuming the truth of the Bible, and then try to find ways to prove it. And that's simply not science.

Still, the creation story in Genesis could be treated as a set of testable scientific hypotheses. This is still problematic, because it's full of miracles, and those are by definition beyond the natural laws that science is concerned with. But the story does make real predictions. For example, the earth should show signs of being just a few thousand years old. Life (human and otherwise) should appear suddenly in the fossil record. The surface of the earth should have features consistent with a massive worldwide flood. What would happen if we tested these predictions scientifically--not with ad hoc ideas crafted to support the young earth theory, but with real, mainstream science? In other worlds, what would happen in a world where radiometric dating methods really work, where the speed of light is constant, where evolution and rock formation are mostly slow, and where floods leave the kind of record we observe real floods leaving? What if we assumed, for the sake of argument, that the world really was created all at once a few thousand years ago, and that most of earth's geologic and fossil record was created in one year by a massive global flood? What would the world be like if that were true? Would it really look like the world we see around us? That's the question I'll try to answer in my next post.



Genesis vs. Geology / Stephen Jay Gould

The Evolution of Creationism / David R. Montgomery

The Rocks Don't Lie: A Geologist Investigates Noah's Flood / David R. Montgomery

Teaching Creationism is Child Abuse / Lawrence Krause