© Paul K. Davis 2009. All Rights Reserved.
Mission Peak Unitarian Universalist Congregation
March 22, 2009


"Next time somebody tells you something that sounds important, think to yourself: 'Is this the kind of thing that people probably know because of evidence? Or is it the kind of thing that people only believe because of tradition, authority or revelation?' And, next time somebody tells you that something is true, why not say to them: 'What kind of evidence is there for that?'" [Richard Dawkins, A Prayer for my Daughter, 1995]

"You shall know the truth, and the truth shall make you free." [Jesus, in John 8:32]

"Science without religion is lame, religion without science is blind." [Albert Einstein]


I urge you to recall the words of Jesus, read earlier: "You shall know the truth, and the truth shall make you free." Think of examples in your life in which you have had to find the truth of a matter in order to know what to do. This could be as mundane as a successful price comparison between two products, or as important as the evidence in a trial if you have been a juror, or anything in between.


You may have noticed in our order of service, that some of the captions for hymns are different today. We commonly sing three hymns, of which the one shortly before the sermon is generally captioned "Hymn of Reflection". I'm an optics physicist, and "reflection" is one of the three primary optical processes, so I have captioned our other two hymns for the other two optical processes: "Hymn of Diffraction" and "Hymn of Refraction". These three processes also have a broader symbolism for me, and I will explain that later in this sermon.

Two thousand and five hundred years ago a boy, born in a region which is now part of the nation of Turkey, was given the name "Anaxagoras". Philosophy was in the air in his time, and he apparently took to it. As a young man he moved to Athens, which is now the capital of the nation of Greece. I credit him with becoming the first known astrophysicist. He heard of a meteorite, an object that had fallen from the sky, and learned that it had been examined, and found to be rock. Anaxagoras concluded that the heavenly bodies were made of rock, rather than some perfect heavenly substance, and taught that the sun shined because it was very hot, not because it was a glorious god.

Horrors! The "enlightened" Athenians banished him. They would probably have lynched him had it not been for the intercession of one of his students, who was a gifted orator named Pericles.

So begins my account of the history of the long and strange interaction of science with religion.

A few decades later a student of a student of Anaxagoras, named Socrates, dealt with the same subject. He said, however, that he did not know what the sun was made of, because he could not go there to inspect it. In so saying he expressed an important principle of science, that our conclusions must be based on actual evidence and that, in the absence of evidence, we should keep an open mind.

Socrates was also a moral teacher, stating that "the unexamined life is not worth living", and telling people, according to Plato in the dialogue "Theaetetus", that they must be born again. His analogy was that his mother, who was a midwife, brought people into physical life, but we also needed to be born into a moral life. But people are often uncomfortable with re-examining their life. As an elementary student once wrote, in answer to the question, "Who was Socrates?" - "Socrates was an ancient Greek. He went around giving everyone advice. They killed him."

Socrates' position on the sun's radiance might have been taken as a compromise, but, to a firm believer, compromises are worse than opposition, and there was no gifted orator to intercede.

The war of religious leadership against those who would understand nature by observing nature, and delving into her processes, did not stop with the end of classical paganism, and its belief that the sun and other heavenly bodies were gods. The medieval Christian leadership took up the cause without, to the best of my knowledge, any justification from the teachings of Jesus. It was proclaimed a heresy to teach that the earth moved in orbit around the sun. Galileo was imprisoned and forced to recant. Giordano Bruno was burnt at the stake.

There is a legend that Galileo, after submitting, quietly said, "Nevertheless, it does move."

The battle easily crossed the Atlantic Ocean, and here in America we have had, for instance, numerous laws prohibiting the teaching of evolution, or requiring the teaching of a religious creation account as if it were science and as if there weren't other religions with other accounts. Recently Stage 1 Theatre brought our community a fine production of "Inherit the Wind", based on the trial of John Scopes for teaching a textbook account of Charles Darwin's Origin of Species, contrary to such a law. I urge you to take any future opportunity you may have to see a production of this play.

Even in these days the religious establishment, together with politicians who do not respect the separation of church and state, are a serious menace to science and our wellbeing. Our recent presidential administration resorted to rewriting NASA scientific reports in regard to global warming, and I applaud my colleague James Hansen for having objected, despite the danger to his job. At any time we may be called on to paraphrase Galileo and say, "Nevertheless, it is getting warmer."

I was also angered to read in the news this past week that pope Benedict said that condoms would hinder, rather than help, the fight against the AIDS virus. He would have the right to say that he considers the use of condoms immoral, but all should criticize him for telling a lie about their effectiveness.

We can, I believe, filter out many false religious teachings by how they treat science. It was an essential condition, for me, before I would join a Unitarian-Universalist congregation, to read the fourth principle endorsing "a free and responsible search for truth and meaning".

But I don't want to imply that I think science is right and perfect, and religion is wrong and always flawed. The line between science and values can also be wrongly crossed the other direction.

From the superb scientific work of Charles Darwin has been drawn the moral philosophy called "Social Darwinism", which Darwin himself, I am confident, would have rejected. Similarly, early in this century many genetics scientists joined the eugenics movement, but the fact that we may know how to control people's breeding does not mean that we should. Many scientists rightly rejected this movement when they saw where it was leading, and how it was being used for evil by the Nazis. I would point out that the progressive philosophy of Michael Dowd, expressed in Thank God for Evolution!, is also consistent with Darwinian theory. Science discovers the facts of nature and how they are related through natural processes and equations which we call, somewhat misleadingly, "laws of Nature". Science does not discover how things should be. We answer the latter question through our moral values, which is the correct province of religion.

Another example can be drawn using a recent book entitled The Bell Curve, by Richard Hernstein and Charles Murray. Among the claims of this book is that there is a correllation between intelligence quotient and race. Much was written among scientists about the erroneous methodology in this book, and its conclusions are not considered scientifically valid. But this book also causes me to think about the separate provinces of science and values. Suppose it had turned out to be true that people of some races have statistically more of some useful quality than other races. This still does not and should not determine how we treat people. As John Goodrum states, at the end of a much more sound review of the status of our scientific knowledge of human variability between and within races, "So if we do belong to different biological races, what, if anything, does this mean?" He then reaffirms "the importance of treating people as individuals." (Incidentally, there is, in fact, less genetic variability between the traditionally identified races, than among people within the same race, and less genetic variability among all people than within many other species.)

Science properly answers questions of fact, and of the processes and patterns among facts. Religion properly answers questions of values, of what our goals should be. We do not, from our values, make pronouncements concerning facts, and we do not make pronouncements of what should be, based simply on how things are or of where things seem presently to be going.

Charles Darwin, in his conclusion to Descent of Man, stated this distinction from the scientific side: "We are not here concerned with hopes or fears, only with the truth as far as our reason permits us to discover it."

Now I'd like to return briefly to the captioning of the hymns.

Diffraction is an optical process which separates light by color; that is, it separates electromagnetic radiation by wavelength. This is not a complete definition of diffraction, but is the aspect which is symbolic for me, namely symbolic of logic. Logic is the process by which we separate our thoughts, concept by concept, to see what our thoughts are made of, and how they are constructed. Logic is fundamental. Our scientific conclusions, and our moral values, alike must pass the test of being logical. Logic, by itself, though, does not tell us what is true or what is good.

Reflection is an optical process which redirects the rays of light in a completely ordered fashion without separating the colors. A mirror can create an image, and this is symbolic to me of the process of science. The goal of science is to create a good image of the universe. It will, of course, be much smaller than the original universe, and lack some of the detail, but no new details are to be artificially introduced. The scientific process depends completely on evidence, just as the mirror depends on the light it receives. It is, by the way, impossible to devise a mirror which does not also have some diffraction, just as it is impossible to do science without logic.

Refraction is an optical process which bends the rays of light. Lenses are an example of refractive devices. To me this symbolizes moral values, whose function is to bend the future, making it different, and hopefully better, than would have been so otherwise. All refractive devises also have some diffractive and reflective effects, just as good moral values must be logical and consistent with the real circumstances of our world.

Thus there are also circumstances in which science and religion must work together. In our fourth Unitarian Universalist principle we recognize that the search for truth must be "responsible". I find a well-stated case-in-hand in the words of George Bernard Shaw, "The right to knowledge is not the only right; and its exercise must be limited by respect for other rights, and for its own exercise by others. the wisest people say, 'If you cannot attain to knowledge without torturing a dog, you must do without knowledge.'"

An example is medical testing. To be confident of test results, a certain minimum number of patients must be tested, and at least half of these must be controls, who do not receive the medicine being tested. Without meeting these scientific requirements we do not find out if the medicine works, which would be to the detriment of many people in the future, but the procedure is to the detriment of the controls. A happy practice, adopted by scientists to respect the value of each person, including the controls, is to evaluate the data part-way through the experiment, so that as soon as statistical significance occurs, if the result is favorable for the new medicine, it can be given to all.

A circumstance in which the needs of science and moral values are consonent, is the selection of test animals. These should be the simplest which have the necessary features for the test. This is good science, because it limits the number of distracting variables. And it is morally good because it causes the least pain with the greatest respect for our cousin creatures. Unfortunately, some nonsensical politicians have criticized experimentation on flies and worms as a waste of money.

I consider myself fortunate in my scientific career always to have had options consistent with my values. I have worked in the field of solar system origin (including the study of meteorites), energy conservation, nuclear reactor safety, computer data storage, and exploration of the universe via infrared radiation. The only position I have quit, completely of my own volition, was from the nuclear reactor corporation, not because I am opposed to safety of nuclear reactors but because, among various concerns, I was disgusted with how the corporation was dealing with the issue.

Science also properly places limits on religion beyond preventing religion from making false proclamations on scientific subjects. I recently learned from PCD Currents, our UU district email newsletter, that Isaac Newton was not just a mathematician and physicist, but also a Biblical scholar who, from studying different Biblical manuscripts, found that two important passages frequently used by trinitarians are in fact later interpolations, not part of the genuine Bible. It is an entirely legitimate function of science to inform religions concerning the truth of their origins, of the authenticity of statements attributed to their founders, etc. By the way, Newton took the precaution of requesting that his writing on this subject not be published until his death.

Before I conclude, I thought I ought to outline the scientific process as I understand it. A scientific inquiry generally starts with examples, termed anecdotal evidence, which bring forth the fact that there is a problem to be solved. Examples, together with previous knowledge, then frame the question(s) to be asked. Statistical evidence is then collected and/or considered. This step is important because it reduces the effect of initial bias - isolated examples are often very misleading. The statistical evidence must contain comparative information (a control). Now, from the statistical evidence, theories are developed which offer some explanatory ability. Interestingly enough, there is no required procedure or any restriction on the development of theories. For example, while we have a single world-wide standard for testing theories, we may accept ideas from any culture or thought system. The testing of traditional medicines is a good example. The theories are next tested in experimental (or quasi experimental) fashion. (I mention "quasi" experimental, because, in some sciences, laboratory experiments are impossible. We cannot build a new star to see what fuel it consumes, or reconstruct the Roman Empire to measure how important slavery was to its economy. We can, however, seek new comparative observations of the phenomena, and observations in other contexts, to test a theory.) Finally, it is an essential part of the scientific process to distribute results, both so they can be verified (or disproved) by other scientists, and so the results can be used as a basis in further scientific work. Examples may again be used to understand the practical effects of the new result as it applies to individual circumstances, and to assist in teaching.

Let me now finish by talking more about my choice of hymns. Our Hymn of Diffraction was "De Colores", and diffraction separates light into its component colors. We sang of the beautiful diversity of colors in nature and among human beings. To understand, we use logic to separate components, and examine how they relate to each other.

Our Hymn of Reflection was "The Harp at Nature's Advent", which praises this glorious universe, whose second verse, for example, talks of mirroring every star. I think of twenty-some years of my own work, on the Spitzer Space Telescope, the Stratospheric Observatory for Infrared Astronomy, and the Kepler mission to identify earthlike planets elsewhere.

Our Hymn of Refraction will be "Though I May Speak with Bravest Fire", based on the words of my namesake, the apostle Paul, in which he points out the vanity of the finest words on these deep subjects without love. We must save mankind by spreading good values, and expressing them in our lives, through our volunteer efforts, through our choice of occupations, through our treatment of our relatives and friends. But we will fail in this if it is not based on a true understanding of the facts of nature. Here is where the dissected parts of our understanding must recombine, as we bend the future.


I quote from our values, that we, as a congregation, affirm and promote a free and responsible search for truth and meaning. Go in peace. Return in love.

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