Christopher Hitchens - The Portable Atheist - Essential Readings for the Nonbeliever

Not all scientists would agree with my bleak view of the final laws. I do not know of anyone who maintains explicitly that there is scientific evidence for a divine being, but several scientists do argue for a special status in nature for intelligent life. Of course, everyone knows that as a practical matter biology and psychology have to be studied in their own terms, not in terms of elementary particle physics, but that is not a sign of any special status for life or intelligence; the same is true of chemistry and hydrodynamics. If, on the other hand, we found some special role for intelligent life in the final laws at the point of convergence of the arrows of explanation, we might well conclude that the creator who established these laws was in some way specially interested in us.

John Wheeler is impressed by the fact that, according to the standard Copenhagen interpretation of quantum mechanics, a physical system cannot be said to have any definite values for quantities like position or energy or momentum until these quantities are measured by some observer’s apparatus. For Wheeler, some sort of intelligent life is required in order to give meaning to quantum mechanics. Recently Wheeler has gone further and proposed that intelligent life not only must appear but must go on to pervade every part of the universe in order that every bit of information about the physical state of the universe should eventually be observed. Wheeler’s conclusions seem to me to provide a good example of the dangers of taking too seriously the doctrine of positivism, that science should concern itself only with things that can be observed. Other physicists including myself prefer another, realist, way of looking at quantum mechanics, in terms of a wave function that can describe laboratories and observers as well as atoms and molecules, governed by laws that do not materially depend on whether there are any observers or not.

Some scientists make much of the fact that some of the fundamental constants have values that seem remarkably well suited to the appearance of intelligent life in the universe. It is not yet clear whether there is anything to this observation, but even if there is, it does not necessarily imply the operation of a divine purpose. In several modern cosmological theories, the so-called constants of nature (such as the masses of the elementary particles) actually vary from place to place or from time to time or even from one term in the wave function of the universe to another. If that were true, then as we have seen, any scientists who study the laws of nature would have to be living in a part of the universe where the constants of nature take values favorable for the evolution of intelligent life.

For an analogy, suppose that there is a planet called Earthprime, in every respect identical to our own, except that on this planet mankind developed the science of physics without knowing anything about astronomy. (E.g., one might imagine that Earthprime’s surface is perpetually covered by clouds.) Just as on earth, students on Earthprime would find tables of fundamental constants at the back of their physics textbooks. These tables would list the speed of light, the mass of the electron, and so on, and also another “fundamental” constant having the value 1.99 calories of energy per minute per square centimeter, which gives the energy reaching Earthprime’s surface from some unknown source outside. On earth this is called the solar constant because we know that this energy comes from the sun, but no one on Earthprime would have any way of knowing where this energy comes from or why this constant takes this particular value. Some physicist on Earthprime might note that the observed value of this constant is remarkably well suited to the appearance of life. If Earthprime received much more or much less than two calories per minute per square centimeter the water of the oceans would instead be vapor or ice, leaving Earthprime with no liquid water or reasonable substitute in which life could have evolved. The physicist might conclude that this constant of 1.99 calories per minute per square centimeter had been fine-tuned by God for man’s benefit. More skeptical physicists on Earthprime might argue that such constants are eventually going to be explained by the final laws of physics, and that it is just a lucky accident that they have values favorable for life. In fact, both would be wrong. When the inhabitants of Earthprime finally develop a knowledge of astronomy, they learn that their planet receives 1.99 calories per minute per square centimeter because, like earth, it happens to be about 93 million miles away from a sun that produces 5,600 million million million million calories per minute, but they also see that there are other planets closer to their sun that are too hot for life and more planets farther from their sun that are too cold for life and doubtless countless other planets orbiting other stars of which only a small proportion are suitable for life. When they learn something about astronomy, the arguing physicists on Earthprime finally understand that the reason why they live on a world that receives roughly two calories per minute per square centimeter is just that there is no other kind of world where they could live. We in our part of the universe may be like the inhabitants of Earthprime before they learn about astronomy, but with other parts of the universe instead of other planets hidden from our view.

I would go further. As we have discovered more and more fundamental physical principles, they seem to have less and less to do with us. To take one example, in the early 1920s it was thought that the only elementary particles were he electron and the proton, then considered to be the ingredients from which we and our world are made. When new particles like the neutron were discovered it was taken for granted at first that they had to be made up of electrons and protons. Matters are very different today. We are not so sure anymore what we mean by a particle being elementary, but we have learned the important lesson that the fact that particles are present in ordinary matter has nothing to do with how fundamental they are. Almost all the particles whose fields appear in the modern standard model of particles and interactions decay so rapidly that they are absent in ordinary matter and play no role at all in human life. Electrons are an essential part of our everyday world; the particles called muons and tauons hardly matter at all to our lives; yet, in the way that they appear in our theories, electrons do not seem in any way more fundamental than muons and tauons. More generally, no one has ever discovered any correlation between the importance of anything to us and its importance in the laws of nature.

Of course it is not from the discoveries of science that most people would have expected to learn about God anyway. John Polkinghorne has argued eloquently for a theology “placed within an area of human discourse where science also finds a home” that would be based on religious experience such as revelation, in much the way that science is based on experiment and observation. Those who think that they have had religious experiences of their own have to judge for themselves the quality of that experience. But the great majority of the adherents to the world’s religions are relying not on religious experience of their own but on revelations that were supposedly experienced by others. It might be thought that this is not so different from the theoretical physicist relying on the experiments of others, but there is a very important distinction. The insights of thousands of individual physicists have converged to a satisfying (though incomplete) common understanding of physical reality. In contrast, the statements about God or anything else that have been derived from religious revelation point in radically different directions. After thousands of years of theological analysis, we are no closer now to a common understanding of the lessons of religious revelation.