Wednesday, February 26, 2014

Pisces for Skeptics

Pisces, from Atlas Coelestis, John Flamsteed
I was born on the Ides of March, the infamous date of the stabbing of Caesar. Call me morbid, but I've always considered it a rather stylish birthdate. Of course, the older I get the more I beware the Ides of March myself. Et tu, birthday?

In any case, my birthdate makes me a Pisces, and that does not strike me as very stylish. Some people have Scorpio, or Aries the war god, or Taurus the bull for a sign, and what do I get? Two fish bound together by a cord. Bor-ing. And Pisces is an unimpressive constellation to look at, too, full of faint, faraway stars.

Still, I've heard about Pisces all my life, and since the Ides of March are drawing nigh once again, I thought I would finally learn something about it. And it turns out that when you take a closer look, Pisces is pretty interesting. Not because it has any influence on my fate or destiny, as the astrologers say. How could it? Most of the stars in the constellation are so far away that the light that left them on the day I was born won't reach Earth until decades after I'm gone. Centuries, in some cases. 

No, what's fascinating about Pisces has nothing to do with me. But does have to do, at least partly, with how people through history have seen it. After all, a constellation is as much as human construction as an astronomical one. If aliens on a distant planet gazed up at the same set of stars, they would see an entirely different pattern, and interpret it differently still. Even other cultures on Earth see it differently. The Chinese, for example, didn't group the stars of Pisces together, except a few of them, which they saw as a fence next to a celestial pigsty. Maybe I should count my blessings that I wasn't born under the sign of the pig fence.

People in the west have seen fish in Pisces at least since the ancient Greeks, and possibly since the Babylonians, who originated many of the constellations we still recognize. In Greek myth, Pisces is associated with Aphrodite and her son Eros. When the awful monster Typhon chased the two of them, they jumped into a river to escape, and were towed to safety by a pair of fish. In other versions of the story, they briefly turned into a pair of fish themselves. Either way, the fish were immortalized by being set amongst the stars.

Pisces is one the twelve constellations of the western zodiac. While most people associate the zodiac with astrology, it has a real basis in astronomy. The solar system is a flat disc, which means the sun, moon, and all the planets seem to follow a single circular path around the sky; a great circle called the ecliptic. The constellations of the zodiac all lie on the ecliptic, so from earth all the bodies of the solar system seem to pass in front of them. People are said to have a certain sign if the sun is passing through that constellation when they're born (well, that's only sort of true, as we'll see). When I was born, for example, the sun was in Pisces.

This convention is a little surprising, if you think about it, because when the sun is in a certain constellation, that constellation appears in the sky in the daytime--which means you can't see it then. The ancients could be pretty sophisticated stargazers. They knew the constellations were still there in the daytime, and that the sun could be passing through one of them even if it's invisible.

Image by Tauʻolunga
Of course, the sun isn't really going around the earth as it passes through the zodiac. We're going around it. To see why the sun seems to move through the zodiac, its useful to imagine the stars as fixed to the inner surface of an immense sphere surrounding the sun and earth, as in the picture to the right. The sun is in the center, and earth circles it. As we go around the sun, the sun seems to move across the sphere, following the ecliptic (the red line). Imagine grabbing a lamppost and swinging around it. If you look past the lamppost as you swing, it will seem to be moving past all the scenery behind it. The sun seems to move past the constellations for the same reason. The constellation it's "passing through" is the one that's currently on the other side of it from us.

But here's a wrinkle in this neat image: compared to the flat disc of the solar system, the earth is tilted on its axis. That's why we have seasons, as most school kids, and a few adults, know. This tilt means that if you projected the equator onto the celestial sphere (as in the white line above), it would be at an angle to the ecliptic. As the earth circles the sun, the sun seems to be south of the equator for half the year, and north of the equator for the other half. The points where it crosses over are the equinoxes. In the image above, the sun is right at the vernal equinox--which is in Pisces. That's the spot it passes on March 21, the first day of spring.

The funny thing is, the vernal equinox used to be in Aries. Back 2600 years ago or so, the vernal equinox marked the beginning of the zodiac--it was called the First Point of Aries (Aries is the first constellation in the zodiac, and Pisces the last). The reason the equinox has moved in the time since is that the earth wobbles. As it spins on its tilted axis, that axis slowly moves in a circle--just as the axis of a top moves in a slow circle as the top spins. This wobble is called axial precession. Right now, the earth's northern axis points toward the north star, Polaris, which is why all the stars seems to spin around Polaris. But this handy navigational aid is a lucky, and temporary, coincidence. As the axis wobbles through its circle, over a period of about 26,000 years, it points to different spots in the sky. That means it will slowly drift away from Polaris. We will have no north star until it happens to align with a different one.

Precession is the reason the equinoxes slowly move through the zodiac, also over a period of 26,000 years (called the Great Year).  Since ancient times, the vernal equinox has moved from Aries into Pisces, and is making its way toward Aquarius (which is why people talk about the coming "Age of Aquarius"). Precession is also the reason lots of people are wrong about what sign they are. The timetable of the sun's path through the constellations has changed. Back in the day it passed through Pisces between February 19 and March 20, so people born in that period are said to be Pisces. But now the sun passes through Pisces between March 11 and April 18. So, a lot of people who think they're Aries are really Pisces, and a lot of people who think they're Pisces are really Aquarius. I'm a Pisces either way, for whatever that's worth.

Position of the vernal equinox. Image by Kevin Heagen
What about the actual stars that compose Pisces? Many of them were named by Arab astronomers, which is why they have names like Al Rischa ("the cord") and Fum al Samakah ("the mouth of the fish"). The ones with Arabic names are visible to the naked eye (the medieval Arab astronomers who named them didn't have telescopes) but they're mostly faint, because they're far away. Very far away. Al Rischa is actually a binary star--two stars orbiting each other. They're 139 light years away, which means the light I see when I look at them now left the stars themselves 98 years before I was born. If I ever want to see them as they were during my lifetime, I'll need to live to be at least 139. I'm not getting my hopes up. As for Fum al Samakah, it's 492 light years away. Fat chance.

However, there are a few stars in Pisces close enough for their light to have reached Earth in my lifetime. But they're small, dim stars that are hard to see. The closest, Van Maanen's Star, is a mere 14 light years away. It's a tiny little thing, only a little bigger than the earth. But it's impressive in its own way. That little star is more than half as massive as the sun. It's a white dwarf--the unbelievably dense, cooling remnant of an older, much bigger star that grew unstable and cast its outer layers into space. Before it did, it would have spent a few million years as an enormous red giant, hundreds of times as wide as the sun. That would have been an extremely bright star in earthly skies, though no human was around at the time to gaze upon it.

As far away as they are, the stars of Pisces are practically in our laps compared what we find deeper in the constellation, when we look out beyond the Milky Way to other galaxies. The gorgeous spiral galaxy known as Messier 74 is 30 million light years away. Even from that distance, we can see bright red clouds of glowing gas, blue clouds reflecting the light of young giant stars forming in the spirals, and dark dust lanes like black coffee in a swirl of cream. In the bottom left in the image below, we can see a star in Messier 74 dying. It's exploding as a supernova, giving off more energy in a few months than our sun ever will in ten billion years.

Messier 74. ESO/PESSTO/S. Smartt
Far beyond the range of Messier 74 we find stranger things. Over 200 million light years away there's a galaxy known as NGC 383. It's not a spiral, but an elliptical galaxy shaped more like an egg. In visible light it looks like a run-of-the-mill member of a group of other elliptical galaxies (the blue patches in the image to the lef), but when astronomers look at it with radio telescopes, they see hidden fireworks. The galaxy is blasting enormous twin jets of charged particles from a massive black hole at its center. Those particles are moving at nearly the speed of light, and each jet is almost a million light years long--dwarfing the galaxy that produced it. It's quite a show.

But by cosmic standards we really haven't gone that far. If we look back billions of light years, we find a stunning cluster of galaxies with the prosaic name of CL 0024+1654. The yellow galaxies in the center make up the cluster itself. This image contains trillions of stars and probably untold numbers of planets--more than you could count in thousands of lifetimes. And we are seeing it as it was when the earth was young. What's even more remarkable, though, are the warped blue galaxies that surround the cluster. Those aren't part of the cluster--they're actually far behind it. The gravity of the galaxies, and the mysterious dark matter that helps hold them together, is bending spacetime so much that it bends light, acting like an enormous lens. That's what creates the twisted images of the blue galaxies--ghostly images from a much younger universe.

Credit: NASA, ESA,H. Lee & H. Ford (Johns Hopkins U.)
As it turns out, Pisces has a lot more going on than I ever realized. Those two boring fish held some secrets that I find pretty stunning. It's not that they have anything to do with my personality or destiny--I just happened to be born with the sun was passing in front of them. Why should they influence my life, except by expanding my mind when I learn about them? And why should I expect them to? Who do I think I am, anyway? It's true that Pisces contains some of the wonders of the cosmos, but what's great is that they're real wonders, not imaginary ones.

Sunday, February 23, 2014

Literally Unbelievable: What Would the World be Like if Genesis Were True?

In the public library where I work we used to have a patron with a very specific routine. He would come in, log onto one of the public computers, and spend some time intently browsing the internet. Then he would come to the reference desk and ask to buy a single blank CD. As I gave it to him, his eyes would light up and he would begin: "Did you know..." What followed was always a mini-lecture on how scientists had something all wrong: the moon is receding from the earth faster than scientists think; the speed of light has changed dramatically over time; continents used to drift much faster than they do know; radiometric dating is totally unreliable.

In his mind, scientists weren't just wrong, but wrong in a very particular way--they were dramatically overestimating the age of the earth and universe. When they claim the universe began 13.8 billion years ago, that Earth began 4.54 billion years ago, or that dinosaurs first appeared around 230 million years ago, they're wrong. Badly wrong. But if you applied the corrections he kept telling me about, all those beginnings would turn out to have happened at the same time--around 10,000 years ago, when God created everything over a six day period. That's what he believed the Bible says, and he wasn't buying any standard scientific view that said differently.

He's not alone. Gallup polls over the last several years show that about 45 percent of Americans think God created humans all at once sometime in the last 10,000 years. Other polls reveal that around 40% believe the entire universe was created at that same time. Similar numbers of people (though it depends on how the questions are worded) believe that all people are descended from Adam and Eve, that humans once coexisted with dinosaurs, and that a global flood once killed most life on Earth, and created most of the fossils we see today. Many of these same people (around 28% of Americans) believe there's significant debate about these questions in the scientific community. But there isn't. In fact, about 97% of scientists believe humans have evolved over time (although 8% think this process was guided by a supreme being.) Just 2% of scientists believe humans have existed in their present form since the creation of the world. So, nearly half of all Americans hold views that are wildly divergent from those of actual scientists, but the majority of them don't realize it.

These Young Earth Creationists (henceforth abbreviated YEC's) are at odds with science in their approach as well as their beliefs. They begin by assuming the creation account in Genesis is literally true. If the evidence doesn't support that view, they ignore it or say it's wrong. Then they go looking for evidence that will. It's simply off limits for them to reject the hypothesis that Genesis is literally true. Ken Ham recently demonstrated this attitude in his debate with Bill Nye. When asked what would change his mind, his answer was, "As far as the word of God is concerned, no, no one's ever going to convince me that the word of God is not true." That may sound admirable to some, but it's not how science works. In science, evidence is king, and no hypothesis is too sacred to be rejected. If my cherished beliefs are contradicted by mountains of evidence, well, they're wrong. And I was wrong to have cherished them so much in the first place. But if they were right, then the evidence will support them. Only then would I know I was justified in believing them.

In my last post, I argued that if YEC's were right, then by now the evidence would have converged to back them up. Scientists around the world, whatever their previous beliefs, would have looked at the data and been forced to conclude that the Earth really is just a few thousand years old, and that humans and all other living things were created in six days. But that's not the conclusion they came to. Instead, by the first half of the 19th century, geologists looked at the evidence and rejected young earth creationism. This was before Darwin's theory of evolution, and in spite of the fact that these geologists were mostly devout Christians who had grown up believing the literal creation story. In the time since, the evidence has led scientists from many other fields to converge on a very different story than the one in Genesis; a story of an enormous, evolving universe that's over a million times older than YEC's believe. To my mind, it's a far grander and more inspiring story.

But what if it had gone the other way? Creationists like to say that all the scientific evidence points to a young earth, but in the opinion of most scientists, it doesn't. But what if it did? What would the world look like? That's the question I want to explore in this post. What kind of world would have actually convinced scientists--even scientists who had never picked up a Bible--that the Genesis story is an accurate description of the birth of the world?

But I'm going to play by real scientific rules here--no ad hoc exceptions to known physical laws (except for the miracles described in Genesis, which I'm going to temporarily accept for the sake of argument.) I'm going to assume the speed of light really is constant over time, that radiometric dating actually works, that continents didn't once race across the oceans, that geologic strata form in basically the way geologists think they do, that major evolutionary change usually happens slowly, and so on. In other words, I'm going to assume that Genesis is true, and discuss what predictions that model makes--without rejecting or modifying most of the fundamentals of modern science. I'm also going to assume God didn't simply create things to look old...except when absolutely necessary, and not just to fool us. For example, I'll allow that he created Adam and Eve as grownups, but not that he left a deceptive pattern of fossils in order to test our faith. Who wants a deceptive God, anyway?

As far as assumptions about the age of the universe go, I'm going to try to be charitable. Some creationists today still basically hold to Archbishop Ussher's calculation that it's about 6000 years old; created around 4004 BC. According to this view, the flood happened right around 2349 BC. Of course, people in Ussher's day didn't know that by 2349 BC, Sumerian civilization was already over a thousand years old, and many of the pyramids of Egypt older than the United States is now.That doesn't keep the people at Answers in Genesis from thinking Ussher was right--they just figure the historians and archaeologists are wrong, in addition to the natural scientists. But I know plenty of YECs don't go to that extreme, so I'm going to assume that creation and the flood happened before the Egyptian and Sumerian states arose--let's say it happened10,000 years ago, and the flood a couple thousand years after that.

From Creation to the Flood

Ok, then. Let's look at the story in Genesis. In the beginning, the universe is described as a dark, watery place. Saying "Let there be light," God illuminates the world, dividing the day from the night, and thereby creating the first day. On the second day God says, "Let there be a dome in the midst of the waters, and let it separate the waters from the waters." He calls the dome Sky. Then he creates the dry land in the midst of the lower waters, which become the sea. The next day he creates all the plants, and the day after that he says, "Let there be lights in the dome of the sky to separate the day from the night; and let them be for signs and for seasons and for days and for years. He created the sun to light the day, and the moon to light the night." In other words, the light on the first day didn't come from the sun. Perhaps it came from God himself.

Right away, we can see that even today's most ardent creationists don't take Genesis completely literally. Genesis describes God creating an actual dome or firmament to divide the waters, holding the upper waters above the dry land below. Then he spreads the stars across inner surface of the dome. This is really how ancient Israelites, and many other ancient peoples, viewed their universe. They believed they lived on a flat earth under a great heavenly dome. The stars were fixed on the dome, but the dome rotated around the north star, which is why the stars stayed in fixed positions relative to each other. The sun, moon, and planets moved relative to the dome, all following the same rough circle now called the ecliptic. Of course, the whole works revolved around the earth, which was assumed to be the center of the universe.

This may sound primitive, but you can't blame ancient people for believing this way. If you really watch the stars, they do seem to cover the surface of a great spinning dome. And on clear days, the dome is the same kind of blue as the waters, so it's easy (if a little alarming) to imagine that we're in a great diving bell, looking through a transparent dome at the waters above. Finally, the sun and moon really do seem to go around the earth. If the earth were spinning like a top around the sun, common sense says it would just throw us all off. Common sense is wrong, but quite understandable.

The point is that if we were truly going to imagine the world as Genesis describes it, we would have to adopt this ancient flat earth/domed sky cosmology. Honestly, I don't know why it doesn't bother creationists more that this is not the world we live in, because it shows in the very first chapter that the Bible is not completely true. If creationists insist that Noah's Ark really existed, why don't they insist that the dome of the sky really exists, too? Because they can't. Everybody but a few flat-earthers accepts the modern view that the earth is round, goes around the sun, and is not surrounded by a great dome (actually, I just talked to a guy who believes in the dome, so maybe I shouldn't jump to conclusions.) The evidence for all this is completely undeniable these days. So, I'm not going to insist for this exercise that we take Genesis quite that literally. Even YECs don't take it that literally, though I do think it's legitimate to ask them why not. So, we'll assume a Copernican universe, even if it's not what Genesis describes.

Returning to the creation narrative, on the fifth day God creates sea life, as well as birds, which "fly above the earth across the firmament of the heavens." He creates land creatures and then humans on the sixth, saying, "And to every beast of the earth, and to every bird of the air, and to everything that creeps on the earth, everything that has the breath of life, I have given every green plant for food.” At this time, then, every animal was an herbivore. Only after the Fall would some of them become carnivores. This means in a world where Genesis was literally true, we would expect all the carnivore fossils from before the flood to have herbivore-type teeth. It follows that no animal would have needed defensive features. Turtles and armadilloes would have been naked, porcupines quill-less, wasps stingless, and cattle hornless.

On the seventh day, God rested. And then a very different account of creation begins, which most biblical scholars consider to have been written by a different author. In this version, God creates the heavens and earth and then immediately creates the first man, Adam, from the dust--and before plants or animals. Then he creates all the plants in the Garden of Eden and warns Adam that if he eats from the Tree of Knowledge of Good and Evil, he will die that day (this turns out not to be true, at least not literally.) Then God creates the animals and lets Adam name them. Finally, he takes a rib from Adam's side, and creates the first woman (later named Eve.) Ever since then, it's been a common assumption that men have one less rib than women. I believed that myself when I was a child. But it's not true.

Soon the story gets darker. The serpent convinces Eve to eat the forbidden fruit. She does, and gives some to Adam. God doesn't kill them for their disobedience, as he had threatened, but he does curse all three. He tells the serpent he'll have to go on his belly and eat dust. Here's a clear prediction: snakes should eat dust. They don't, obviously. Also, before this curse, serpents presumably had legs. That seems to imply that we could look for leggy serpent fossils from before the Fall, but that won't work, because there was no death before the fall, and thus no dead animals to fossilize. Perhaps we could get very lucky, and find a fossilized snake skin with legs. We could also ask when snakes stopped talking, because Genesis doesn't say God struck the serpent dumb. 

Adam and Eve were also cursed. Eve and all other women are cursed with painful childbirth, and with being ruled over by men. To Adam, God says:
cursed is the ground because of you;
    in toil you shall eat of it all the days of your life;
thorns and thistles it shall bring forth for you;
    and you shall eat the plants of the field.
By the sweat of your face
    you shall eat bread
until you return to the ground,
    for out of it you were taken;
you are dust,
    and to dust you shall return.
Concerned that Adam might also eat from the Tree of Life and become immortal, God expels the first couple from the garden. While Genesis doesn't use the terms "original sin" or "fall of man," traditional Christian doctrine holds that Adam and Eve's original sin of disobeying God caused their fall. This meant none of their descendents would deserve salvation, and could only be saved through God's grace and Jesus' death on the cross. Secular sorts like me wonder why God would punish all of Adam and Eve's descendents (and all the animals, for that matter) for a crime they didn't commit. Is that really just?

In any case, now we've got enough of the narrative to really start thinking about how the world would have looked if the creation story were literally true. Let's start with living things. Most creationists believe death didn't exist before the fall, and that now-extinct animals like dinosaurs and mammoths were killed by Noah's flood. This means every species that ever lived would have coexisted in the world before the flood. That's a whole bunch of species. Even though there are several million species today, over 99% of all the species that have ever lived are now extinct. Before the flood, trilobites, plesiosaurs, and whales would have shared the seas. Great forests of tree ferns would have coexisted with maples and oaks. Dinosaurs, mastodons, and alligator-sized amphibians would have lived side by side with actual alligators, monkeys, songbirds, and every other animal. It would have been a crowded world.

One wonders how the land could have supported all those animals (not to mention terrestrial bacteria, protists, and fungi). Today, fertile soils are normally created over many years from a combination of organic matter (dead things) and eroded bedrock. If everything was created all at once, God would have had to create some soil for it to live on as well. Otherwise, the land would have just been bare rock at first. Death, falling leaves, and erosion hadn't had time to occur. Not only that, but if modern geologists are right about the rock cycle, there would have only been igneous rocks like basalt and granite. Igneous rocks are the basis for other rocks in the the cycle, so metamorphic and sedimentary rocks wouldn't have existed at first, unless God created them pre-formed. Then they would only appear to have been made from pre-existing rocks.

Most creationists seem to think most sedimentary rocks in the geologic column, or at least most of the ones containing fossils, were created by the flood. That means sediment from before the fall, if it existed, would contain no fossil organisms--death didn't exist yet, after all. The only fossils would be trace fossils such as animal tracks and burrows, shed skins and antlers (would pre-fall deer have needed antlers?), fallen leaves, and so on.

If the YEC's are right, we would expect the geologic column to be divided into four basic layers: pre-fall at the bottom, then a post-fall/pre-flood layer, a flood layer, and a post-flood layer at the top. While the pre-fall rocks would only have trace fossils (albeit from an unbelievable diversity of organisms), the post-fall/pre-flood rocks would contain fossils formed from dead organisms (all kinds of organisms, not just the simple ones we actually do find in the oldest fossil bearing layers.) Many of them would have horns, claws, armor, shells, or spines. The world then had grown rough. There would be signs of predation and disease--occasional predator fossils with prey still inside them, bones with teeth and claw marks scattered by scavengers, joints deformed by age and infection. The transition between the two layers would be quite distinct, unless the flood were violent enough to rearrange it all (many creationists think it was, but this has its own problems).

How the pre-flood world would have looked depends in many ways on how God actually created it. But one thing we can be sure of is that the night sky looked utterly different, especially at first. When Adam was first created, he would have looked up to see a sky devoid of stars. That's because even the closest stars are light years away. It would have been years before the first ones appeared (unless they really are just lights in the firmament, and nobody believes that nowadays, even if the authors of Genesis did.) In Adam's 930-years lifetime, he would have seen most of our familiar stars pop into view. By the end of his life it would have been a glorious sight in those pre-industrial skies, but he never would have seen the band of the Milky Way as we can today in dark places. The galaxy is over 100,000 light years across, so he would have only been able to see a fraction of it.

In fact, if the world is really 10,000 years old, we would only be seeing a fraction of it. Even astronomers wouldn't be able to see the center of the galaxy, because its light hasn't had time to reach us. We would have little idea of how the galaxy was shaped, and never suspect the universe contained billions of other galaxies, all flying away from each other. The closest galaxies are much too far away for their light to have reached us in a mere 10,000 years. The only way we could see anything beyond this range is for God to have created the universe with the light already most of the way to Earth. And then, if you think about it, it would be carrying images of things as they were ages ago--before they ever existed. The light would be lying! Surely God wouldn't go to those lengths to deceive us? Maybe it's easier to believe that when we see young galaxies billions of light years away, that's because the universe is actually billions of years old, not because God is scamming us?

While we're talking about indicators of age, what about the dating methods scientists rely on? If the world were really 10,000 years ago, all the methods capable of dating that length of time, including tree ring records, ice cores, annual deposits in lakes, and radiocarbon dating, would all agree--but not in the way they already do. Instead, they would all go back a few thousand years and stop. We could probably calculate the age of the earth down to the year. We might even be able to use pollen grains to pinpoint the season. Of course, that's assuming the flood wasn't violent enough to annihilate most of records from the pre-flood years. If it did, then all these dating methods would simply tell us how long ago the flood happened. Longer-term dating methods based on radioactive elements with long half-lives wouldn't be useful, because not enough time has passed for them to work. Trying to use them to measure anything on a 10,000 year old planet would be like trying to measure a bacterium with a yardstick. Those kinds of radioactive elements would hardly have decayed at all, and the earth would be a much more radioactive place.

After the fall, things kept going from bad worse. Cain slew Abel and was cursed by God, but he finally found a wife (where did she come from?) and started having children. It was a violent age, apparently. Lamech, the father of Noah, boasted to his wives that he had killed a youth for striking him, and went on to declare that those who hurt him would be avenged not just seven-fold, but seventy-seven fold. This makes the "eye for an eye" traditions of later ages sound positively forgiving.

Looking down on all this,
5 The Lord saw that the wickedness of humankind was great in the earth, and that every inclination of the thoughts of their hearts was only evil continually. 6 And the Lord was sorry that he had made humankind on the earth, and it grieved him to his heart. 7 So the Lord said, “I will blot out from the earth the human beings I have created—people together with animals and creeping things and birds of the air, for I am sorry that I have made them.” 8 But Noah found favor in the sight of the Lord.
Once again, other living things will suffer for humanity's sins.

At God's command, Noah built the great ark, whose dimensions would have been roughly 450 feet long and 50 feet wide. It's not clear just how many animals he put on the ark. Genesis 6:19 says God told him to take two of every kind, while Genesis 7 says he took 7 pairs of all clean animals and birds, and one pair of all the rest. Either way, that's a lot of critters. If nothing had yet gone extinct, then there would have been hundreds of millions, and probably billions, of species. Of course, many of these were plants, fungi, and bacteri (and how did they survive the flood?) but there would still have been many millions of animals--most of them small arthropods, but many of them quite sizeable. Now, if the animals that are extinct today were the ones left off the ark, then that drops the number by quite a lot. How Noah decided which ones to save is an interesting conundrum, but the Bible is silent on that issue. Somehow all these millions of animals made their way from all around the globe--wallabies from Australia, sloths creeping from South America, tuataras and kiwis from New Zealand--and filed onto the ark. I'm not going to get into the logistics of all this too much. That's been done by other people whose patience and abilities far exceed mine. Suffice it to say I'm skeptical.
Once the animals and Noah's family were safely aboard:
11 In the six hundredth year of Noah’s life, in the second month, on the seventeenth day of the month, on that day all the fountains of the great deep burst forth, and the windows of the heavens were opened.
It seems to me that whoever wrote these lines believed in the ancient flat earth/domed sky cosmology. They imagined water from above pouring through the dome, and water from the primordial deep rising up to bury the dry land once again. Wherever the water came from, it rained for 40 days and nights, and the floodwaters rose for 150 days, until they covered the tops of the mountains to a depth of 15 cubits. But then the waters began receding, and the ark came to rest in the mountains of Ararat. Late in the eleventh month, Noah sent out a dove to look for dry land, and it returned with an olive branch (how did an olive tree survive the flood?). Finally, just over a year after the flood began, Noah, his family, and all the animals began to emerge from the ark. I imagine they were yearning for some fresh air.

After the Deluge

What kind of world would Noah have stepped out of the ark to gaze upon, if Genesis were literally true? It's hard to say, because it would depend on exactly how the flood happened, and how violent it really was, and Genesis doesn't go into that much detail. It does say the highest mountains were covered, and modern YEC's take that literally. The summit of Mt. Everest is over 5 miles above sea level, so this would mean the water got that deep over the entire surface of the earth. That's far more than all the known water on Earth, so the first question is where it came from. Genesis says it fell from the sky and also bubbled up from the "fountains of the deep", and YEC's have taken both routes. Some have said there was once a great "vapor barrier" high above the Earth, and others that the water mostly came from within the Earth. But if it was once in the atmosphere, the atmospheric pressure would have flattened every living thing, and if it bubbled up from the Earth it would have been blistering hot--Noah and everything else on the ark would have been steamed like broccoli. Some creationists claim the flood dramatically reshaped the Earth's topography: erasing most previous traces, lifting the fossil-bearing rocks that cap Everest five miles above the surface, laying sediment miles deep in places like the Grand Canyon, and then carving deep canyons in it--all within a few months. But any flood that violent would have obliterated the ark with heat and tsunamis. Besides, it just wouldn't work. Floods don't create sediment, turn them to stone, and then use it to build mountains and carve canyons--not in just a few months, certainly, because they don't do that at all. 

So, it's tough to say what kind of world the flood would have created. If there were already mountains, then they would be made entirely of igneous rock, unless God had also created sedimentary and metamorphic rock in the beginning. The flood would have left the same kind of deposits around the world; not the complex layer-cake strata we see in places like the Grand Canyon, or the twists and folds of high mountains, but a fairly uniform layer with heavier rocks and sand toward the bottom, and mud toward the top. This wouldn't have solidified into rock during the flood, as creationists say, and most of it wouldn't have turned into rock even now. If by some miracle, it did, then the rock record from the flood would be a coarse conglomerate on the bottom, and a layer of mudstone on top. 

What about fossils? Would the flood have stacked them neatly, layer by layer, so that simple organisms at the bottom gradually give way to to mammals, birds, and flowering plants at the top? Would it only leave humans at the very top, as the real geologic record shows? No. If all the living things that ever lived were mostly killed in the flood, then organisms from all geologic ages recognized by geologists would all be jumbled together. There would be differences from region to region, because different assemblages of fossils would form in different parts of the world (unless living things were created in the Middle East, in which case they wouldn't have had time to populate distant islands and continents, and there be few if any fossils in Australia and the Americas.)

YECs like to claim that the changes in the fossil record from bottom to top are based on three things: that some animals sink and some float, that smarter, more complex animals ran to higher ground, and that the flood took strata from very different parts of the world and stacked them neatly on top of each other. None of these notions makes any sense. The last is just ludicrous. Any flood powerful enough to lift blankets of rock and deposit them elsewhere in the world would have torn those rocks apart (and smashed the ark to bits in the process.) Perhaps some of the smarter animals could have headed for the hills and thus gotten into the higher layers, but surely some of them--the old and injured, perhaps--wouldn't have made it? Surely a few extinct animals-- flying pterosaurs, perhaps--would have made it to the high ground? If this hypothesis worked, we would find some light and agile dinosaurs in the top layers, and some slow humans deep down, mixed in with the early amphibians or trilobites. We don't, but we would if Genesis were literally true. And what about plants? They can't run at all. The fossil record shows modern flowering plants appearing "recently", in the higher layers. If all the plants already existed when the flood hit, we would find grass and flowers in the bottom layers, and the older conifers, which already live in the high mountains, at the top.

As for the idea that some animals float better than others, that might cause some sorting. Noah and his family would have looked out across the floodwaters to see countless bloated, floating corpses: people, elephants, dinosaurs of all descriptions, and so on. That does mean we would expect to find more of those creatures toward the top, and heavy or sedentary animals like oysters and corals at the bottom. But in the actual fossil record, we often find "primitive" sea creatures like oysters and corals in layers above dinosaurs. These kinds of creatures may have appeared earlier in the fossil record in the real world, but unlike dinosaurs, they're still with us. So, if a swamp full of dinosaurs is later covered by a shallow sea (which often happened in earth history) then there will be "primitive" sea life above the dinosaurs, in younger rocks. Flood geology has an awfully hard time explaining that.
270 million year old footprints, Grand Canyon

Even if the flood could have somehow stacked all the strata we find today, as YEC's think it did, the record in those rocks would be completely different. The geologic column is full of features--and at many levels--that simply couldn't have formed in the middle of a global flood: dinosaur nests, surface tracks, glacial scars, animal tracks and burrows, desert dunes, charcoal from fires, volcanic ash falls, mud cracks, salt and gypsum left behind by evaporation, and many more. No, if the Genesis record were really true, none of these things would exist in the rock record. It would just be one big, chaotic layer of rock, mud, bones, and shells. Most of it wouldn't have even turned to rock by now.

What about biology? After the flood, Noah would have looked out on a world devoid of live plants (except that one miraculous olive tree). Perhaps some plants could have regrown from seeds from the ark, or floating seeds that survived the flood, but at first there would have been nothing for the herbivores to eat. The toughest carnivores would be OK for a while, because they would just eat other animals. But without plants to support terrestrial ecosystems, they would soon die, too. Many of the animals that survived the flood, then, would have died soon after they left the ark. It wouldn't help that each of them (including the humans) would have been carrying the full complement of parasites that specialize on them--worms, flukes, lice, and others best not discussed. Even if most of the "lucky" flood survivors weren't killed by the post flood devastation--if God miraculously replanted the earth, for example--how did they all file back to the places we find them today? Did most marsupials have instructions to head for Australia? Did lemurs pass through Africa without leaving any descendents, and then swim over to Madagascar? Even if all the animals did miraculously find their way back to their homelands, we would see genetic signatures of the flood. Everything on the ark, including humans, would show clear signs of a genetic bottleneck from the time there were only a handful of them. Many of them would go extinct from this kind of inbreeding. Currently widespread creatures, such as humans, would show genetic signs of having originated in the Middle East. We would be much less genetically diverse. Africans, Asians, Australian Aborigines, and Europeans would look much more similar--there would be about as much physical difference between the world's peoples as we see among Native Americans, who really did likely descend from single populations several thousand years ago. 

I could go on and on like this, but this post is getting awfully long, and I'm tired of this stuff. The point is that if the Genesis creation narrative really were true, we would live in a very different world--probably a logically incoherent and inhospitable world. Luckily, we don't. We don't have to engage in all the tortured, procrustean thinking that YEC's impose on themselves. We don't have to contort our intellects to invent explanations for why the world is just a few thousand years old, even if it seems so very much to be billions of years old. We can just accept that it is billions of years old. Then we can breathe a sigh of relief, and follow the evidence where it leads. That doesn't necessarily mean we have to become atheists. Lots of very smart people have no trouble reconciling Christianity and the ancient earth described by modern science. It just means we have to let go of the idea that Genesis is completely and literally true. It just isn't, and its authors may never have wanted us to think it was. It's a powerful story, but it's just that--a story. It's not science. Science has its own story to tell, and it's a powerful one, too; a story of countless galaxies and unimaginable spans of time; of fabulous beasts living in ancient and bizarre worlds that preceded our own. For my money, it's a far more intellectually-satisfying story--grander and more coherent than the Genesis version. Best of all, it doesn't require me to assume I've already been given the truth, or to hang signs around my mind saying, "Off limits."


Evolution: What the Fossils Say and Why it Matters / Donald Prothero

Evolution, Climate Change, and Other Issues/ Pew Research Center

Evolution, Creation, Intelligent Design / Gallup

The Fatal Flaws of Flood Geology / Christopher Gregory Weber

Finding Darwin's God: A Scientist's Search for Common Ground Between God and Evolution / Kenneth Miller

Fossil Tracks and Other Trace Fossils Refute Flood Geology / Glen Kuban

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 Doré
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

Tuesday, February 4, 2014

Going to Extremes: Coke Commercials, Diversity, and Why We're More United than We Think

The Golden Rule - Norman Rockwell
Why is it that the most spirited public debates in this country seem to revolve around pop culture and processed food? We've had dust-ups over Chick-Fil-A, Miley Cyrus, Duck Dynasty, and now it's a Coke commercial aired during the Superbowl. The commercial features people singing "America the Beautiful" in many different languages, and that got some folks pretty riled up. Sure, there are wars and massive human rights violations going on around the world, and the NSA is still vacuuming up every piece of personal data it can find about us, but somehow those things just don't spark our interest as much.

Still, the fact that there are bigger issues out there doesn't necessarily mean these commercial controversies are trivial. Gay rights are an important issue, despite the rather circus-like atmosphere of the Chick-Fil-A and Duck Dynasty debates. The Coke commercial controversy is about a real issue too, because it shows the divisions in our views about what the United States of America, culturally speaking, is and ought to be. I thought the ad was kind of beautiful, though I try not to let myself get too moved by commercials. But others disagreed, and some of them showed a really hateful, xenophobic side when they did. Apparently these hateful tweeters don't realize that the actors and singers in the commercial are Americans, many of whom were likely born in this country and speak perfect English, in addition to their other languages.

So, I came down squarely on the liberal side regarding the commercial, but I found I can't fully agree with either side when it came to the debates about it. Obviously, I couldn't agree with the conservative view. I kept seeing people talking as though "American" and "English-speaking" were somehow inseparable, and who seemed to think that singing "America the Beautiful" in any other language should be taken as a deliberate insult. That point of view completely mystifies me. Maybe somebody singing that song in, say, Arabic really does think America is beautiful? I know Americans who could sing the song in English or Arabic, and they would mean every word of it in either one.

Then I noticed a guy, who didn't approve of the commercial, talking about all the things he thought liberals hate about America. That was a little confusing, because I'm a liberal, and I don't hate America, and I don't know any other liberal who does, either. Yes, we're more likely than conservatives to acknowledge the country's flaws and failings, from slavery to arrogant foreign policies, and we're more likely to disagree with the idea that our country can do no wrong. But that's not remotely the same as hating America. Liberals (and many conservatives) tend to reject "my country right or wrong" thinking. We think more like the German-American senator and general Carl Shurz, who said, "My country, right or wrong; if right, to be kept right; and if wrong, to be set right." And we love our country.

But then I noticed that it's not just conservatives accusing liberals of hatefulness. The same guy who said liberals hate America also kept making the point that liberals were always calling him a racist for his conservative opinions, such as thinking all immigrants should learn English. I don't know if he's a racist or xenophobe or not--lots of people who hated that commercial obviously are--but he's got a point in this case. Thinking it would be a good idea for everyone in a country to have a common language is not racist. In fact, I think it's a good idea, too, just because it would help people understand each other and help the country function more smoothly, not because I think there's anything particularly sacred about English. I'm sure many immigrants agree with me, too. But I also think it would be a tragedy if people didn't pass on their other languages to their children.

I do think liberals are too quick to accuse conservatives of hatred and racism. Yes, some of them are hateful and racist (and so are a few liberals). But many of them aren't, and I don't blame them for being frustrated at being called something they aren't. I know I don't like being told I hate America. So, maybe we should reserve terms like "hatred" and "racism" for the real things, instead of throwing them around every time someone disagrees with us. There's plenty of real racism and hatred we still have to deal with, after all.

This phenomenon, where both sides think the other is more extreme and hateful than they really are, is well known to psychologists. Oftentimes, what's really extreme is not the opinions of those we disagree with, but our misjudgement of what they really think. In one important study, psychologists asked people across the political spectrum to fill out a questionaire about their moral beliefs. Then they took self-described liberals and conservatives and asked liberals to fill out the questionaire as though they were a "typical conservative", and asked the conservatives to fill it out as though they were a "typical liberal". The results were amazing. Not only did people think typical or average members of the other party were more extreme than the actual averages, they thought they were more extreme than actual self-reported "extreme liberals" and "extreme conservatives". In other words, liberals think the average conservative is farther right than most people on the actual far right. And vice versa. Not only that, but people think the average on their own side is more extreme than it really is. No wonder we're always accusing each other of being extremists, even though most of us aren't.

Of course, there are real extremists and truly hateful people out there, and that Coke ad flushed some of them out. But any fool with a computer can post on Twitter, so in a country with 300 million people, it's no surprise that you'll be able to find some nasty haters out there. We all knew they were out there, didn't we? What we have to stop doing is thinking a few extremists are typical of everyone on that side of the spectrum. They aren't. If we want to heal the divisions in this country, maybe the first thing we should do is realize we aren't as divided as we think we are.