Tuesday, February 25, 2014

Two Debates

There have been two very recent debates between high-profile Christians and scientifically-minded opponents.

I'm not that interested in the Ken Ham vs. Bill Nye the Science Guy debate, as Ham's creationist views have no credibility whatsoever. It would be interesting to see what approach Bill took. Some reviews have been positive, others not so.

I'm much more interested in the William L. Craig vs. Sean Carroll debate. Unfortunately, there doesn't seem to be video available for it yet. [ETA: Video now available here.] WLC is infamous in atheist circles for "winning" most of his debates. ("Winning" is of course very subjective in informal debates like these, but when the folks on the opposing side think you won, you probably won.) Carroll is not only a cosmology expert, he is one of the most philosophically astute scientists I know of - he's light-years ahead of Lawrence Krauss or Jerry Coyne, in my opinion. So Carroll is probably the ideal opponent for WLC. Props to WLC for taking on Carroll on his home turf: cosmology. This was either very brave or very stupid of him.

Carroll's own views on the debate are here. (I don't see any comments on it on Craig's website yet.) I think it's not just atheistic bias to assume that, where they disagree on the cosmology, the cosmology expert is probably right.

One new thing I learned from Sean's comments: Some cosmologies have a Boltzmann Brain problem and others don't. That's something I'll have to learn more about.

Craig has employed modern cosmology extensively in the past, both in debates and in his published papers. I was glad to see that Sean brought up the big problem with this: some cosmological models have an infinite past. Others don't. None of these models is considered established physics. So cosmology tells us nothing (yet!) about whether the universe had a beginning or not.

I really like Sean's five responses to the fine tuning argument - especially his #2, which is basically the same as my Fine Tuning Argument for Naturalism. Craig apparently had no response to this point.

There's been a lot of discussion about whether these debates are a good idea or not, from the point of view of promoting science and rational thought, much of it focussed on whose resume will be enhanced and whose pockets will be filled. From the purely intellectual point of view, I'm all for them. It's true that debates are a poor format for getting to the truth, but they're a great format for exposing folks to ideas  they might not have encountered otherwise.

Saturday, February 22, 2014

Evolution and Entropy, Again

I just got an email from someone who had read my essay about evolution and the second law of thermodynamics and thought he had found a flaw in it. It made me realize that the discussion there is rather technical and mathematical, and I ought to write up the basic idea in a clear and non-mathematical way. So here goes.

The thermodynamic argument against evolution goes something like this:
  1. Evolution involves an increase of order, and therefore a decrease of entropy.
  2. The second law of thermodynamics says that entropy never decreases.
  3. Therefore, evolution contradicts the second law of thermodynamics.
Let's first consider (1.). In order to establish this, one would have to show that the body of a human being has less thermodynamic entropy than an equal mass of bacteria  (for instance). Now, this may in fact be true, but no one has ever proven such a thing, to my knowledge. Without proving (1.), the argument can't get off the ground.

Secondly, even if (1.) is true, the argument fails, because (2.) is wrong: the second law of thermodynamics doesn't say that entropy never decreases.

In fact, entropy decreases spontaneously in lots of natural settings: for instance, when a pond freezes over in winter. Ice has much less entropy than liquid water - if it were impossible for entropy to decrease then it would be impossible for ponds to freeze over.


So what does the second law of thermodynamics say? It says that there can't be a decrease of entropy in one place without a compensating increase of entropy somewhere else. In the case of the pond, the heat escaping from the water during the freezing process causes an increase of entropy of the air over the pond.

If you wanted to prove that the freezing of the pond violates the second law of thermodynamics, you would have to calculate the entropy decrease of the water, calculate the entropy increase of the air, and show that the latter is less than the former.

In the case of evolution, you would have to calculate the entropy decrease due to cells being "organized" into higher life forms, which, we already noted, has never been done. Then you would have to show there was no compensating increase of entropy elsewhere. This second step is what I addressed in my essay. If we take the whole Earth as our system, then we find there is an absolutely enormous increase of entropy due to the radiation of heat energy into space. This entropy increase is so large that no possible decrease of entropy due to evolution would cause a violation of the second law of thermodynamics.

Wednesday, February 12, 2014

Victor, Meet Ken

Victor Reppert's blog, Dangerous Idea, has been on my blogroll for a while. I try to look for blogs that express the theist's viewpoint in an intelligent manner, and Reppert is a Christian who has some philosophical acumen and whose  arguments have often seemed worthy of consideration. Recently, though, his posts have been declining in both length and quality. Now he has hit a new low. Here's a recent post, in its entirety:

Atheists often make the claim that the burden of proof lies with the believer, not the unbeliever. They would ask whether you can prove that the nonexistence of anything. Rather, it should be up to the person who makes the positive claim to provide proof, not the people trying to prove a negative. 
However, there are many things that are invisible that I might have trouble proving. Let's take electrons,  for example. I've never seen one myself. Many people believe in them simply on the authority of scientists. People also believe in God, even though they can't see God, because they take his existence on the basis of authorities. What's the difference?
Here's the difference, Victor: anyone who disbelieves the authorities can repeat the experiments on their own. Electrons, you say? How about the Millikan oil drop experiment, the Compton effect, the q/m experiment, the Franck-Hertz experiment? How about examining the fine structure of hydrogen? If you're unsure about electrons, try one of these experiments and see what you get. I've done several of them myself, and can vouch for the results.

Of course it's up to the person making the claim to provide the proof. And scientists have done that - and published their results - and repeated those demonstrations again and again for generations of students.

Please tell me, Victor, how do I go about repeating the results of the religious "authorities"? 

You can go to a Chinese physicist, a Russian physicist, a South African physicist, a Brazilian physicist, an Australian physicist, and ask them the charge of the electron, and they will all give you the same answer.

If I go to a Hindu religious authority, a Muslim  religious authority, a Roman Catholic religious authority, a Sikh religious authority, a Buddhist religious authority, and a Shinto religious authority, will they give me the same answer to my religious questions?

Whole industries now rely on our understanding of electrons. Every time you make a phone call, watch TV, or type a blog post, you are effectively performing an experiment that confirms the properties of electrons.  We trust that understanding enough to stake our very lives on it, every time we get on a plane, train, or automobile.

What discoveries or declarations of religious authorities are so reliable that people all over the world stake their lives on them?


"What's the difference," you ask?

One word: EVIDENCE

Saturday, February 8, 2014

Against Cause

In an attempt to gain a better understanding of modern views of causation, I've been reading Causation and Explanation, by Stathis Psillos. So far what I've learned is this: modern views of causation are a mess. There are intrinsic and extrinsic views, reductive and non-reductive views, the "marker" view, and the "conserved quantity" view. There is no agreement on whether Hume's regularity view of causation needs to be improved upon, or abandoned and replaced with something quite different.

Over at The Edge, there is the annual Edge Question event. This year's question: What scientific idea is ready for retirement? Go read the responses, they're very interesting and very short.

Among the responses, W. Daniel Hillis suggests we retire the concept of cause and effect. Causes, he suggests, are just parts of a story we tell about the world.

Science is a rich source of powerful explanatory stories. For example, Newton explained how a force causes a mass to accelerate. This gives us a story of how an apple drops from a tree or a planet circles around the Sun. It allows us to decide how hard the rocket engine needs to push to get it to the Moon. Models of causation allow us to design complex machines like factories and computers that have fabulously long chains of causes and effects. They convert inputs into the outputs that we want.
 These stories can be very useful, but they can also be misleading.
It is tempting to believe that our stories of causes and effects are how the world works. Actually, they are just a framework that we use to manipulate the world and to construct explanations for the convenience of our own understanding.

So maybe the reason philosophers can't find a decent characterization of causes is that they are not really a part of the universe. Rather, they are something we invent - maybe in a rather haphazard and inconsistent manner - to help us track important aspects of the world around us. 

Thursday, February 6, 2014

Where's Evil?

Where's evil? It's that large part of every man that wants to hate without limit, that wants to hate with God on its side.

(Kurt Vonnegut, Mother Night)