Friday 21 February 2014

Douglas Wilson's Letter From Moscow

Building Things With Sunshine

Blog and Mablog

I have said in the past that I think evolution is a hoot, and moreover, I have given reasons for thinking this. One of the reasons is that the idea of evolution runs clean contrary to the second law of thermodynamics. In response to this view of mine, an anti-theist web site (read more here) has offered the following:

“To finish this argument (hopefully once and for all) I will give a similar example but in relation to life.-
In ‘open’ thermodynamic systems energy is imported to turn simple compounds into complex ones, a perfect example of this is photosynthesis in which; water and carbon-dioxide are turned into complex carbohydrates.
The energy for this is imported from the sun, because the earth is not a ‘closed’ system, it is an open one.
If evolution is impossible relating to the second law, so is photosynthesis, which is obviously not the case.”

Let me go straight to my conclusion, state the problem, and then work back to the argument. My interlocutor is trying to explain things with photosynthesis, when what he needs to do is give an accounting for photosynthesis.


Entropy does apply in a closed system. Let’s say that I lock a bunch of plastic up in a box, and I figure out a way to keep it a closed system, keeping all new energy out. That plastic will degrade over time. Give it enough time, and we will have ourselves a little plasticine-like heat death in there.

Okay, now make it an open system. Unfold the box so that it is now a slab, and put the whole thing out in the mid-day sun. New energy is beating down on that stuff like nobody’s business. All this will do is accelerate the entropy. It won’t make the plastic into the intelligently-designed object that I have in mind for my illustration here, which would be a simple Zip Trip coffee cup with a logo on the side — a thousand times less complicated than any living cell. The energy from the sun will just speed up the degradation. With me so far?

But my questioner, taking me for a doofus, tells me in a learned voice that of course I am not going to get a plastic cup as a result of the sun beating down on a pile of plastic, for pity’s sake. But what I have done, says he, is that I have completely left out of my calculations this 3-D printer that is over here in this corner of our slab, and it can make plastic cups all day long — and it has a little solar panel on top that makes it run on sunlight. All the plastic cups you could ever want.

“Great,” say I. “How did the sun build the 3-D printer? That’s way more complicated than a plastic cup.”
In other words, in order for energy to be put to productive use, in any way that runs contrary to entropy, you need an exquisitely designed mechanism that can do that, and such a mechanism also requires an accounting. If it is a piece of marvelous engineering, I do confess that this makes some of us rubes think of a marvelous engineer.

You can’t just wave your hands over the magic photosynthesis machine, and say, “See?” Because many of us do see, and one of the things we see is the manufacturer’s information printed on the side of that thing.

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