Evidence, Doctrine, Theory and Truth

A recent cover article in Christianity Today issue addressed the re-thinking among some evangelicals about the existence of a historical Adam and Eve.  Christian doctrine has traditionally taught that all human beings are descendants of an original pair formed directly by God by a special creation, or perhaps God taking two hominoids and transforming them into full human beings, from which are descended all humans.  Archeology, now reinforced by genetic studies, instead suggests that all human beings are descendants of a population of at least several thousand individuals that existed at a point between 100,000 and 150,000 years ago.  The article is reasonably fair and respectful, trying to do justice to views of people on different positions on the debate, identify the critical issues involved, and calling for cooperation in working through the tensions and against open clashes among believers that have too often marred such discussions.  I commend the authors for that.

The critical underlying issue is the apparent incompatibility of current scientific theory regarding genetic diversity and the prevalent Christian doctrines regarding original sin and the fall.  In very simplified terms for those not so familiar with each, genetic theory says that in addition to mutations that are a clear benefit or detriment, there are also those that don't make a lot of difference (e.g. blue eyes vs. green eyes) that slowly accumulate in a population over many generations; by measuring how much diversity there is now and making some reasonable assumptions about the rate of accumulation of variation, one can estimate the minimum number of genetically distinct individuals that existed a certain number of years ago.  Original sin says that the first couple sinned in disobeying God, and as a result have passed that sin nature onto all of their descendents, something that took the perfect obedience of Jesus Christ in life and death to break its power.  One couple vs. many clearly forms conflicting claims, and they both can't be right.

As I am neither a theologian nor a geneticist, I do not seek to resolve the conflict here.  Rather, I'd like to discuss the related but not identical concepts of evidence, theory, doctrine and Truth.  I believe productive discussions of controversial topics like this require a healthy understanding of the differences.  First, capital-T Truth is not something any human being or organization has a lock on.  Complete understanding of the universe we live it is simply beyond any one or group of human beings.  In the physical realm, it is simply far too complex for anyone to really know more that a small slice, and there are limits on knowledge, from the quantum mechanical uncertainty principle that says one can't have perfect knowledge of a particle, the speed of light that limits how fast information can travel, to limits on our ability to gather information-my astronomy colleagues tell us that 96% of the mass/energy in the universe is of some form that almost none of the current detection methods can see.  In the spiritual realm we have only the limited amount of revelation that God has chosen to provide, which comes to us in the language of ancient human authors, which can be sometimes ambiguous and cultural dependent.  This is not to say we can't know anything, but neither a scientific theory nor a Christian doctrine are the same thing as Truth.  Both are human constructs that correspond to a greater or lesser extent to the Truth that we can't know completely.  The actually serve similar functions in their respective disciplines, providing us a framework for making since of the myriad of related facts and encapsulating the best understandings for passing on to the next generation.  The theories and doctrines that are widely taught today are the ones that won out over others because they provided a better fit to the evidence.  The type and nature of the evidence they utilize tend to be quite different; science relies heavily on observations and experimental results to establish theories, while doctrines rely more on scriptural interpretation, tradition and individual impressions.  I do not believe that either theories or doctrine are intrinsically more reliable than the other; consulting a physics text on how to treat my wife and the Bible on how to build an airplane are equally foolish. Some theories are far more established than others with much stronger evidence, and the same goes for doctrines.  There is good evidence for them, so they are not to be lightly tossed aside because we don't like them or a few pieces of evidence seems to conflict.  But even the most established theories and doctrines are not the same as the Truth, so we must not conflate the two and be prepared to rethink even the most cherished theory or doctrine if the evidence warrants it.  The goal should not be to prove my theory or doctrine is right, but to better approach the Truth.

Thank God for the Big Bang

I thank God for the Big Bang. Seriously. After all, if there was no beginning of our universe, there would be no universe, no Sun, no Earth, no life and no people. But beyond providing for our existence, the Big Bang is one piece of evidence that points me to the Creator.

The evidence is quite strong that our universe exploded into existence in a cosmic fireball of unimaginable heat and density somewhere around fourteen billion years ago. There are multiple lines of evidence that support this. One is the recession of galaxies; based on the shifting of the wavelengths and the relative brightness of light coming from distant galaxies and supernovas, there is a clear pattern that the further away from us a galaxy is, the faster it is moving away from us. Second is the cosmic microwave background, a radio-wavelength signal that comes at us nearly uniformly from every direction in the sky. The best explanation on offer for that is “fossil” light from the early universe when atoms stated to form, that has had its wavelengths stretched to radio signal lengths by the expansion of the universe. Third is the relative abundance of elements in the primeval matter of the universe. There is still a lot of gas that has yet to be incorporated into stars or planets in our universe, which consists mostly of hydrogen, a little helium and traces of lithium. The relative abundances of these, which are consistent everywhere we can look, are best explained by a model in which the dense early universe past briefly through a phase in which it was cool enough for atomic nuclei to be stable but still hot and dense enough for some nuclear reactions to occur. Forth is the presence of heavier elements, such as carbon, iron and lead. These are not found in “pristine” matter in the universe, but rather are products of nuclear reactions in stars, with the heaviest elements like lead and gold being created in a supernova explosion when a massive star turns into a giant hydrogen bomb and blows the majority of its mass into surrounding space; once there some can be incorporated into new stellar systems, the way it appears to have happened for our solar system. With the even the shortest-lived stars having estimated lifetimes of several billion years, it took time to create all the iron and gold we use, but a much older universe would contain much more of that than what is observed. Coupled with observations from geology of sedimentation, crust renewal, fossils and various methods of radioactive dating, there are multiple lines of evidence that point to a beginning point in the distant past for the universe we live in.

It is these multiple lines of evidence, largely independent of each other but all pointing in the same direction, that gives us such strong confidence that the Big Bang is a fairly accurate description of what actually happened. Any one piece of evidence might be misinterpreted or could be explained by an alternative theory, but when taken together, a single theory that explains all these different observations is far more likely to be true than a set of unrelated, ad hoc theories that each just explain one observation. In the same way, I believe that there are quite a few different pieces of evidence that point to the existence of a God who created the universe and (surprisingly) is somehow involved in the affairs of ordinary people. There is no smoking gun or one piece that people have not already attempted to explain away, but put together they give me a high level of confidence that God is not a product of human imagination but a real being and the force behind the universe and that which is in it.

For many years I have read, listened and pondered about what science, scripture, and other lines of inquiry can tell us about the nature of the universe we live in. A synthesis has slowly formed in my mind, weaving together insights from diverse fields that I believe does them justice and gives me a more comprehensive view of the world we live in. But much of that has happened in isolation, and I hope this blog I am starting can be a forum to think about these issues more in community. If I am misleading myself or have misunderstood things, I need other people point that out. On the other hand, if I am right about some of these things, I think I have a moral obligation to share with others so that they can draw on any good insights I might actually have. I’d like to invite you to join me on this endeavor, following my blog as I post thoughts about once a week, making comments to keep me honest and asking questions if things are not clear. My desire is to write such that it is understandable and engaging for a wide range of areas of study and religious beliefs, which is more challenging but I believe ultimately more rewarding. Please keep that in mind as you interact with this blog.

Image: Artist's rendering of a supernova explosion, (c) NASA, retrieved from http://www.nasa.gov/images/content/175872main_sn2006gy_main_330.jpg