Fifteen or more years ago my professional writing and research interests were largely focused on the philosophical implications of various interesting and important issues in the sciences, particularly the theory of natural selection in biology and philosophy’s contributions to cognitive science (an interdisciplinary investigation of consciousness and the brain involving biology, neuroscience, physics, psychology, linguistics, philosophy, and several other disciplines). For a number of reasons my professional research and writing energies have shifted over the years, but I still have a fond place in my heart for the intersection of philosophy and science. So when I read an essayist the other day compare the Christian claim that Jesus was both human and divine to the famous “uncertainty principle” in physics, my virtual ears perked up. With apologies in advance for oversimplification to my colleagues and friends in various physics departments, let’s take a look.
The uncertainty principle was introduced by Werner Heisenberg in 1927 as a statement of one of the most fascinating and mind-bending features of the world of quantum physics. The principle states that the more precisely the position of some particle is determined, the less precisely its momentum can be known, and vice versa. In other words, you cannot know both the position and the speed of a particle at the same time. The notion that two directly measurable quantities of the same physical particle cannot be nailed down simultaneously sounds odd, to say the least, but philosophers have long grappled with the problem of how to handle two truths that are both obviously and logically true yet are incompatible with each other.
Dualistic philosophers, for example, claim that a human being consists of two fundamentally incompatible things, a physical body and a non-physical mind. Yet we know experientially that our bodies and minds interact with each other all the time—something mind and body should not be able to do if they are substantially different. So are they really different sorts of things or not? Princess Elizabeth of Bohemia once pressed the great René Descartes so vigorously on this in their letter correspondence–How can mind and body be different substances and still interact in the human person?—that he finally wrote, in essence, “I don’t know. They just do.” Not a great philosophical argument, but at least he tried.
Which brings me back to the Ian Frazier essay I mentioned in the first paragraph that got me to thinking about all of this. Frazier writes that
Whatever Jesus actually looked like, trying to adjust him to any physical image is misleading, because he was both God and man. This concept is so powerful, yet so challenging, to hold in the mind that whole huge heresies have thrown in the towel and simply picked one side or the other. I try to think of Jesus as being a sort of oscillation between the two. A similar idea in physics is the uncertainty principle, which says you cannot know both the position and the speed of a particle at the same time. Jesus was God and man oscillating back and forth—either and both, both or either, simultaneously.
That’s a peculiar notion, to say the least—I’m kind of picturing Jesus in an endless dance between two incompatible states at such speed as to make mere mortals unable to tell that he’s moving at all. I’m not sure it’s very helpful theologically. But this got me to thinking about another possible application of quantum craziness to Christianity: “Uncertainty Principle Jesus” is nothing when compared to another hybrid of Christianity and physics: “Schrödinger’s God.”
One of the strangest features of quantum physics is that atom or photon can exist as a combination of multiple states corresponding to different possible outcomes—a situation called a “quantum superposition.” We know that superposition actually occurs at the subatomic level, because there are observable instances in which a single particle is demonstrated to be in multiple locations at the same time. One of the leading quantum theory interpretations says that an atom or photon remains in this indeterminate superposition until it is observed, before which only probabilities can be predicted. We cannot know with certainty ahead of time which of the various states the atom or photon will settle into. The act of measurement affects the system, causing the set of probabilities to reduce to only one of the possible values immediately after the measurement. Yet another demonstration of the apparent conflict between what quantum theory tells us is true about the nature and behavior of matter on the microscopic level and what we observe to be true about the nature and behavior of matter on the macroscopic level — everything visible to the unaided human eye.
In 1935 Austrian physicist Erwin Schrödinger came up with a thought experiment that drives the point home directly, a thought experiment that has come to be known as Schrödinger’s Cat. Place a living cat into a steel chamber, along with a device containing a vial of hydrocyanic acid, a radioactive substance. If even a single atom of the substance decays during the test period, a relay mechanism will trip a hammer, which will, in turn, break the vial and kill the cat.
But given quantum superposition, we cannot know whether or not an atom of the substance has decayed, and consequently cannot know whether the vial has been broken, the hydrocyanic acid released, and the cat killed. Since we cannot know, according to the quantum superposition of states, the cat is both dead and alive. It is only when we break open the box and learn the condition of the cat that the superposition is lost, and the cat becomes one or the other (dead or alive). This situation is sometimes called quantum indeterminacy or the observer’s paradox: the observation or measurement itself affects an outcome, so that the outcome as such does not exist unless the measurement is made.
Scientists, philosophers, and fiction writers have had a field day with Schrödinger’s poor cat for the past eighty years; Schrödinger himself is rumored to have said, later in life, that he wished he had never met that cat. Further discussion of the scientific implications of a world in which things at a foundational level are radically uncertain until we interact with them is well above my knowledge and pay grade. But transfer Schrödinger’s thought experiment to a classic question from an entirely different field of human inquiry: Does God exist? The traditional and common sense assumption is that there is a solid “yes” or “no” answer to this question—something either exists or it doesn’t, right? The issue then becomes “what do you mean by ‘God’?’ and “what evidence do you consider to be relevant to the question?” The fact that things immediately spin out of control in terms of complication and confusion does not obviate the fact that the original question—Does God exist?—sounds for all the world like a simple “yes” or “no” sort of question.
But in a Schrödinger world, even that isn’t clear. Just as in a world of physical indeterminacy Schrödinger’s cat is both alive and dead until someone looks, so in a world of theological indeterminacy God both exists and does not exist—until someone looks. As long as the discussion is abstract and verbal, no progress can be made and no conclusions can be drawn. But as soon as one commits to action rather than abstractions, something happens. Just as one finds the cat either dead or alive when the box is opened, so one finds a living or dead deity when one engages actively. What one finds is not simply a function of what’s going on “out there.” It is equally a function of what one brings to the activity of looking. We tend to find what we are looking for. At the very least, the God question is answered experientially, not intellectually. For the blind man who said after Jesus had left town that “I was blind, and now I see,” his new faith was based on an experience, not argumentation. Before the experience, no argument would have convinced him. After the experience, no argument was necessary.