So, via Panda’s Thumb, I hear that Granville Sewell is up to his old hijinks. Sewell is a classic creationist crackpot, who’s known for two things.
First, he’s known for chronically recycling the old “second law of thermodynamics” garbage. And second, he’s known for building arguments based on “thought experiments” – where instead of doing experiments, he just makes up the experiments and the results.
The second-law crankery is really annoying. It’s one of the oldest creationist pseudo-scientific schticks around, and it’s such a terrible argument. It’s also a sort-of pet peeve of mine, because I hate the way that people generally respond to it. It’s not that the common response is wrong – but rather that the common responses focus on one error, while neglecting to point out that there are many deeper issues with it.
In case you’ve been hiding under a rock, the creationist argument is basically:
- The second law of thermodynamics says that disorder always increases.
- Evolution produces highly-ordered complexity via a natural process.
- Therefore, evolution must be impossible, because you can’t create order.
The first problem with this argument is very simple. The second law of thermodynamics does not say that disorder always increases. It’s a classic example of my old maxim: the worst math is no math. The second law of thermodynamics doesn’t say anything as fuzzy as “you can’t create order”. It’s a precise, mathematical statement. The second law of thermodynamics says that in a closed system:
- is the entropy in a system,
- is the amount of heat transferred in an interaction, and
- is the temperature of the system.
Translated into english, that basically says that in any interaction that involves the
transfer of heat, the entropy of the system cannot possible be reduced. Other ways of saying it include “There is no possible process whose sole result is the transfer of heat from a cooler body to a warmer one”; or “No process is possible in which the sole result is the absorption of heat from a reservoir and its complete conversion into work.”
Note well – there is no mention of “chaos” or “disorder” in these statements: The second law is a statement about the way that energy can be used. It basically says that when
you try to use energy, some of that energy is inevitably lost in the process of using it.
Talking about “chaos”, “order”, “disorder” – those are all metaphors. Entropy is a difficult concept. It doesn’t really have a particularly good intuitive meaning. It means something like “energy lost into forms that can’t be used to do work” – but that’s still a poor attempt to capture it in metaphor. The reason that people use order and disorder comes from a way of thinking about energy: if I can extract energy from burning gasoline to spin the wheels of my car, the process of spinning my wheels is very organized – it’s something that I can see as a structured application of energy – or, stretching the metaphor a bit, the energy that spins the wheels in structured. On the other hand, the “waste” from burning the gas – the heating of the engine parts, the energy caught in the warmth of the exhaust – that’s just random and useless. It’s “chaotic”.
So when a creationist says that the second law of thermodynamics says you can’t create order, they’re full of shit. The second law doesn’t say that – not in any shape or form. You don’t need to get into the whole “open system/closed system” stuff to dispute it; it simply doesn’t say what they claim it says.
But let’s not stop there. Even if you accept that the mathematical statement of the second law really did say that chaos always increases, that still has nothing to do with evolution. Look back at the equation. What it says is that in a closed system, in any interaction, the total entropy must increase. Even if you accept that entropy means chaos, all that it says is that in any interaction, the total entropy must increase.
It doesn’t say that you can’t create order. It says that the cumulative end result of any interaction must increase entropy. Want to build a house? Of course you can do it without violating the second law. But to build that house, you need to cut down trees, dig holes, lay foundations, cut wood, pour concrete, put things together. All of those things use a lot of energy. And in each minute interaction, you’re expending energy in ways that increase entropy. If the creationist interpretation of the second law were true, you couldn’t build a house, because building a house involves creating something structured – creating order.
Similarly, if you look at a living cell, it does a whole lot of highly ordered, highly structured things. In order to do those things, it uses energy. And in the process of using that energy, it creates entropy. In terms of order and chaos, the cell uses energy to create order, but in the process of doing so it creates wastes – waste heat, and waste chemicals. It converts high-energy structured molecules into lower-energy molecules, converting things with energetic structure to things without. Look at all of the waste that’s produced by a living cell, and you’ll find that it does produce a net increase in entropy. Once again, if the creationists were right, then you wouldn’t need to worry about whether evolution was possible under thermodynamics – because life wouldn’t be possible.
In fact, if the creationists were right, the existence of planets, stars, and galaxies wouldn’t be possible – because a galaxy full of stars with planets is far less chaotic than loose cloud of hydrogen.
Once again, we don’t even need to consider the whole closed system/open system distinction, because even if we treat earth as a closed system, their arguments are wrong. Life doesn’t really defy the laws of thermodynamics – it produces entropy exactly as it should.
But the creationist second-law argument is even worse than that.
The second-law argument is that the fact that DNA “encodes information”, and that the amount of information “encoded” in DNA increases as a result of the evolutionary process means that evolution violates the second law.
This absolutely doesn’t require bringing in any open/closed system discussions. Doing that is just a distraction which allows the creationist to sneak their real argument underneath.
The real point is: DNA is a highly structured molecule. No disagreement there. But so what? In the life of an organism, there are virtually un-countable numbers of energetic interactions, all of which result in a net increase in the amount of entropy. Why on earth would adding a bunch of links to a DNA chain completely outweigh those? In fact, changing the DNA of an organism is just another entropy increasing event. The chemical processes in the cell that create DNA strands consume energy, and use that energy to produce molecules like DNA, producing entropy along the way, just like pretty much every other chemical process in the universe.
The creationist argument relies on a bunch of sloppy handwaves: “entropy” is disorder; “you can’t create order”, “DNA is ordered”. In fact, evolution has no problem with respect to entropy: one way of viewing evolution is that it’s a process of creating ever more effective entropy-generators.
Now we can get to Sewell and his arguments, and you can see how perfectly they match what I’ve been talking about.
Imagine a high school science teacher renting a video showing a tornado sweeping through a town, turning houses and cars into rubble. When she attempts to show it to her students, she accidentally runs the video backward. As Ford predicts, the students laugh and say, the video is going backwards! The teacher doesn’t want to admit her mistake, so she says: “No, the video is not really going backward. It only looks like it is because it appears that the second law is being violated. And of course entropy is decreasing in this video, but tornados derive their power from the sun, and the increase in entropy on the sun is far greater than the decrease seen on this video, so there is no conflict with the second law.” “In fact,” the teacher continues, “meteorologists can explain everything that is happening in this video,” and she proceeds to give some long, detailed, hastily improvised scientific theories on how tornados, under the right conditions, really can construct houses and cars. At the end of the explanation, one student says, “I don’t want to argue with scientists, but wouldn’t it be a lot easier to explain if you ran the video the other way?”
Now imagine a professor describing the final project for students in his evolutionary biology class. “Here are two pictures,” he says.
“One is a drawing of what the Earth must have looked like soon after it formed. The other is a picture of New York City today, with tall buildings full of intelligent humans, computers, TV sets and telephones, with libraries full of science texts and novels, and jet airplanes flying overhead. Your assignment is to explain how we got from picture one to picture two, and why this did not violate the second law of thermodynamics. You should explain that 3 or 4 billion years ago a collection of atoms formed by pure chance that was able to duplicate itself, and these complex collections of atoms were able to pass their complex structures on to their descendants generation after generation, even correcting errors. Explain how, over a very long time, the accumulation of genetic accidents resulted in greater and greater information content in the DNA of these more and more complicated collections of atoms, and how eventually something called “intelligence” allowed some of these collections of atoms to design buildings and computers and TV sets, and write encyclopedias and science texts. But be sure to point out that while none of this would have been possible in an isolated system, the Earth is an open system, and entropy can decrease in an open system as long as the decreases are compensated by increases outside the system. Energy from the sun is what made all of this possible, and while the origin and evolution of life may have resulted in some small decrease in entropy here, the increase in entropy on the sun easily compensates this tiny decrease. The sun should play a central role in your essay.”
When one student turns in his essay some days later, he has written,
“A few years after picture one was taken, the sun exploded into a supernova, all humans and other animals died, their bodies decayed, and their cells decomposed into simple organic and inorganic compounds. Most of the buildings collapsed immediately into rubble, those that didn’t, crumbled eventually. Most of the computers and TV sets inside were smashed into scrap metal, even those that weren’t, gradually turned into piles of rust, most of the books in the libraries burned up, the rest rotted over time, and you can see see the result in picture two.”
The professor says, “You have switched the pictures!” “I know,” says the student. “But it was so much easier to explain that way.”
Evolution is a movie running backward, that is what makes it so different from other phenomena in our universe, and why it demands a very different sort of explanation.
This is a perfect example of both of Sewell’s usual techniques.
First, the essential argument here is rubbish. It’s the usual “second-law means that you can’t create order”, even though that’s not what it says, followed by a rather shallow and pointless response to the open/closed system stuff.
And the second part is what makes Sewell Sewell. He can’t actually make his own arguments. No, that’s much too hard. So he creates fake people, and plays out a story using his fake people and having them make fake arguments, and then uses the people in his story to illustrate his argument. It’s a technique that I haven’t seen used so consistency since I read Ayn Rand in high school.