Quantum physics requires that minds be non-physical

In a recent article in First Things, "Faith and Quantum Physics," Stephen M. Barr argues that quantum physics, one of the most non-common sense, and also one of the most successful, theories of modern science, requires that human minds be non-physical. As Barr points out, he is not the first to say this -- other prominent thinkers have done so. He also points out that some of the opposition to the seeming weirdness of quantum physics is because of exactly this conclusion.

Barr's argument goes like this:

Predictions of any kind, made as statements of probability, such as, for example, which party will win the U. S. Presidential election of 2004, are meaningless unless they predict a measurable actual outcome. There was an election, and the Republicans won, however that happened, and whatever has become of it. Quantum physics makes predictions about physical systems, in the form of mathematical equations. (There are no equations in Barr's article) But these are usually measured by laboratory devices, which are, themselves, physical systems, and the same mathematical equations apply to them, and are only predictions. Says Barr:
And this leads to the remarkable conclusion of this long train of logic: As long as only physical structures and mechanisms are involved, however complex, their behavior is described by equations that yield only probabilities-and once a mind is involved that can make a rational judgment of fact, and thus come to knowledge, there is certainty. Therefore, such a mind cannot be just a physical structure or mechanism completely describable by the equations of physics.

There is more in Barr's article, for sure. He also says that quantum physics is more congenial to Judeo-Christianity than it is to Buddhism, and that quantum physics presents strong arguments against determinism, or, in other words, for free choice. He finally examines the different philosophical views that are used to explain the findings of quantum physics, and comes down as in favor of the approach of Neils Bohr, although he understands that Bohr's thinking had some weak spots.

It is refreshing, but should not be surprising, that a physicist states that a great scientific theory provides evidence that a mind is not simply a material object, and that such minds make real choices. After all, God's revelation includes the natural world, as well as the Bible.

Thanks for reading.

Francis Crick, atheist

I recently read Francis Crick: Discoverer of the Genetic Code, by Matt Ridley. (New York: HarperCollins, 2006) The title itself should strike a careful reader as curious. In the first place, Francis H. C. Crick is best known for the discovery of the double helix, with Watson, not for the discovery of the genetic code. In the second, genetics textbooks, and other sources, such as the Wikipedia article on the genetic code, do not give Crick much, if any credit for cracking the code whereby sequences of messenger RNA are transformed into sequences of amino acids.

But there is something to the claim that Crick was the discoverer of the genetic code. Francis Crick theorized about protein synthesis. Secondly, Crick (who was not known as an experimentalist) did do critical experiments that led to the realization that the code was a triplet code. Ridley describes how Crick also was the catalyst that cajoled others into doing the work that led to the discovery. In that, he appears to have been something like Neils Bohr, who, collaborating with many scientists, lectured, thought, wrote and discussed, playing a pivotal role in the discovery of quantum physics in the previous century.

Watson, in his best-selling The Double Helix, began by writing that he had "never seen Francis Crick in a modest mood." Ridley is not modest in his biography, as he anoints Crick as "the greatest biologist of the twentieth century" (p. 5). No doubt that claim, however important, could be disputed. (Eugene Odum, Edward O. Wilson, and Niko Tinbergen, and many others might merit consideration.) Nonetheless, Crick was important. It is unfortunate that he was an atheist. (So was Watson, unless he has made a radical change recently.)

Ridley says that what really motivated Crick was a desire to discredit vitalism, the idea that living things cannot be explained and understood completely in terms of physics and chemistry. Crick believed that they could be so explained. So did many other scientists. Depending on what is meant by explanation, so do I. Crick and Watson apparently felt that they had explained life when the DNA helix was proposed. Crick went on to study consciousness, which he was continued to do until the end of his life, as, says Ridley, the last bastion of vitalism. He did not live to see the achievement of his goal of being able to understand consciousness in terms of neuron activity. We are probably a long way from that yet.

What is meant by explanation? If, by explanation, we mean that we can, at least in principle, describe how a cell works, in chemical and physical terms, most biologists of today would agree. This has not yet been done, at least not completely, but, within my lifetime, enormous strides have been made. I would not be surprised to see the construction of a working living cell, capable of metabolism and reproduction, produced from laboratory chemicals, in the first half of this century. There does not seem to be any reason to suppose that any aspect of cell function cannot be explained and understood in terms of the chemistry of the cell. Does this rule out Divine action? Certainly not. In principle, it is possible to understand, say, all the parts, and the functioning, of a Ford Explorer. If I did so understand it, that would not mean that it wasn't a wonderful piece of equipment, nor would it mean that it wasn't designed and planned. In the same way, even if we did understand all of the molecular activity of organisms, it wouldn't make their existence any less wonderful, nor would it rule out supernatural design and planning.

If, by explanation, we consider some other questions, such as "How did life begin?" "Why do Carbon atoms and other chemical entities have the properties that make life possible?" "Why are humans interested in this sort of question?" then we can't explain life. Crick, nor anyone else, has done so, and I don't believe it is possible to do so. (More and more plausible naturalistic answers for the first question may be produced, but they will never amount to a certain description of what actually did happen.) Crick, in fact, according to Ridley, put forward panspermia as an explanation for the origin of life on earth, at least half-seriously. Why would an otherwise intelligent person consider that living things may have been placed here by extraterrestrials, and reject that they were placed here by a supernatural being?

It is unfortunate that Crick, who was noted for discussing serious issues for extended periods with intelligent people, including, or especially, when they didn't agree with him on all points, didn't really come to grips with the issues of the meaning of life, and the origin of living things, and the universe that makes them possible. Perhaps he didn't really want to come to grips with these questions. Perhaps he was turned off by interpretations of the Bible that claim to rule out some of the important findings of science. I don't know. But it is unfortunate.

Thanks for reading. God's best in the New Year!

Chance and 20th Century physics, 2

The previous post on this topic is here. In it, I discussed the Heisenberg uncertainty principle, and quantum physics in general. Some thinkers have believed that the unpredictability of sub-atomic particles is the explanation for free choice in the human brain.

Albert Einstein, who was, of course, one of the pillars of twentieth century physics, including quantum physics, is renowned for many things. One of them is that he said something like "God does not play at dice." (in German) Another is his long argument with Neils Bohr, another of the titans of twentieth-century physics, about quantum physics. (The Wikipedia article on Bohr includes a photo of Einstein and Bohr, engaged in this long argument.) These facts are often taken to mean that Einstein believed that everything can be predicted, at least in principle, or that he disbelieved in quantum physics. Apparently this is not completely correct.

I have recently read a book which deals with the subject of Einstein, indeterminacy, Bohr, and quantum physics, Einstein Defiant: Genius versus Genius in the Quantum Revolution, by Edmund Blair Bolles. Washington, DC: Joseph Henry Press, 2004. (The two geniuses are Bohr and Einstein.) Bolles puts Einstein's saying this way: "I, at any rate, am convinced that He is not playing at dice." Quote is from p. 252. Bolles' source is Max Born's Born-Einstein Letters, translated by Irene Born. New York: Walker Publishing, 1971. Bolles says that the statement was in a letter to Born, also an important physicist.

Bolles argues that what Einstein really meant was that indeterminacy, or unpredictability, does not imply that there are not real causes, even for the actions of sub-atomic particles. Some of his colleagues were, it seems, willing to believe that all we could do is predict these actions statistically, not individually, and that what happened to an individual particle was simply a matter of chance. Einstein apparently agreed, except that he would not have agreed with the last clause. He believed that, if we could just perceive them, there are real influences, even on sub-atomic particles.

I suppose that Einstein's view, if correct, means that quantum uncertainty cannot be the foundation of human free will.

Thanks for reading.

Michael Frayn's Copenhagen

My wife was good enough to go to see a production of Michael Frayn's Copenhagen with me on Father's Day, at Centre Stage South Carolina. She assigned me to report to our daughters on our attendance. (She also pointed out a grammatical mistake. Thanks!) I decided to do this as a blog post.

This play won the Tony award (best Broadway play) for 2000. It was an amazing choice. There are only three characters, all playing dead people, on a bare stage. The plot is that the dead people, Werner Heisenberg, Neils Bohr, and Bohr's wife, Margrethe, are trying to understand a visit Heisenberg made to Bohr, in Copenhagen, in 1941, by discussing it, over and over. There's enough physics in the play that I once assigned the script for a physics class to read.

Based on this description, the play doesn't sound like much, but it is. There are many interesting aspects of our lives explored during Copenhagen. Can we really ever understand ourselves? Is memory accurate? Why do we do things? What is the responsibility of a scientist for the application of that scientist's work? Do humans perceive reality, or determine it?

Bohr and Heisenberg were two of the greatest physicists of the past century. Heisenberg, like many others, studied under Bohr, in Copenhagen, Denmark, where Bohr lived. During, or before, World War II, many of the physicists of Europe, ethnic Jews, left. Heisenberg did not. He was in charge of Germany's nuclear physics program. He did go to see Bohr. Frayn's play dramatizes real uncertainty about why he went, and what they said to each other. The play works in Heisenberg's Uncertainty Principle, which tells us that we cannot accurately measure both the momentum and position of sub-atomic particles, and Bohr's Complementarity, which says that a sub-atomic particle can present itself as either a wave or a particle, depending on how it is measured. Although neither of these ideas was supposed to be about ordinary human knowledge, both of them have influenced our thinking about how we know, and what reality is. (So has Einstein's Theory of Relativity, which, again, was not supposed to be about moral absolutes, but about measuring movement of one physical system from a second one, but has influenced our thinking about moral absolutes*.)

Historians are not clear about what happened during Heisenberg's meeting with Bohr, except that these people, who had been great friends until that time, had a falling out during this meeting. Frayn dramatizes this lack of clarity, having the actors suggest that Heisenberg was trying to use Bohr to find out about Allied work on nuclear fission (the atomic bomb), or to get Bohr's advice on the production of an atomic bomb, or that Heisenberg was trying to tell Bohr that he, Heisenberg, would try to deliberately hold back the German nuclear program, or that Heisenberg wanted Bohr's blessing for working on a project which might protect Heisenberg's country from destruction by the Allies, even though Bohr was in Denmark, occupied by the Germans.

Both men survived the war. Both were invited to give Gifford lectures, a noted and long-running series of prestigious lectureships on natural theology. According to the play, Heisenberg was generally shunned by physicists after the war, even though, as Frayn put it, Heisenberg had not built a fission bomb which destroyed two cities--the scientists working for the Allies had.

The Bulletin of the Atomic Scientists was founded by some of the scientists who helped produce fission bombs, questioning, after the fact, the impact of their scientific offspring. It is still discussing the implications of nuclear weapons, almost sixty years after their testing and use. One of its features is the Doomsday Clock, which represents how close we are to nuclear war. Currently, it is set at seven minutes to midnight.

There was a discussion after the play, and perhaps a third of the audience stayed for it. The leaders tried to center it on the moral responsibility of scientists for the application of their work, but it ranged further. My belief is that scientists are partly responsible for the forseeable consequences of the application of their work, and might be morally obligated, under some circumstances, to stop working in certain areas. The only time that I know of when that happened was at the Asilomar Conference on recombinant DNA in 1975, and even in that case, most of the research which was questioned then is now being done, and perhaps all of it will be, including germ cell DNA engineering (changing the DNA of a sperm or egg, or cells which produce them).

My only contribution to the discussion was when a lady said that there were no absolute moral standards, in response to one of the leaders, who said that there are, and that they come from a supernatural God. I remarked that her statement was itself an absolute. The leader got her to agree that there was at least one thing (raping a two-year-old) that was absolutely wrong. The discussion pointed out that one argument for actually using the fission bomb was that the deaths caused would be far less than if the Japanese had been defeated more conventionally.

I thought about asking three questions. First, is a scientist responsible for how the public sees reality as a result of her work (see remarks on relativity, the uncertainty principle, and complementarity above)? Second, could, or should, such a play be written about the invention of gunpowder (my wife says guns--she's probably right) rather than the fission bomb? Third, the play brought out that Heisenberg was an accomplished musician. It didn't bring out, but it is true, that Bohr was a student of philosophy (as was Einstein, and most of the European physicists of the first half of the previous century). I don't believe that most scientists in the U. S., nor, probably, the rest of the world, are as versed in the humanities as those of Bohr's times. If this is true, is that dangerous? Shouldn't scientists know more than science?

My wife and I certainly were gripped by the play, and were glad we went. It wasn't merely entertainment.

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*Rebecca Goldstein has recently written on how the work of Einstein, and of Kurt Gödel, a great mathematician, both of them fierce believers in an objective reality, was used to argue that there is no such thing.