Recently, I had the pleasure of being a guest on an old friend’s podcast, The Christian Humanist Podcast.  Nathan and I went to high school together, and were part of the same church, and in particular, the church’s high school youth group.  He went on to pursue English literature in college, while I went on to study the weather.  Many years later, I discovered his blog while searching for Christian resources on the Internet, and we  reconnected through there.

The podcast discussed science and its relationship to Christian inquiry.  The hosts of the Christian Humanists are students of philosophy and the humanities, and as such I was very interested to hear their perspective on that other great human intellectual pursuit–Science.  I thought we had a great conversation, and I learned a great deal (which I will likely discuss in future posts), but wished we could have had more time to pursue some of the issues that came up in our discussion.  This post is an attempt to elaborate on one of them, namely the idea that science is progressive.

First I want to lay some background by discussing what the changeable nature of science means.  One common thread I’ve noticed amongst non-scientists is a conception that science is always in a state of flux.  What is true one minute may be shown to be false the next.  While this is certainly true, there is another very important aspect to consider.  Namely, science always builds on what came before.  There is always a solid bedrock of time-tested knowledge on which to fall back on.  As Newton famously said, “If I have seen a little further, it is by standing on the shoulders of giants.”  In this regard, it is quite similar to other intellectual fields such as philosophy or theology.  Philosophers, theologians, and scientists alike never operate in a vacuum (unless they are literally studying the vacuum, of course!).  They always at least consider what other philosophers and theologians have said, and test their ideas in relation to them.  This is not to say that they don’t question fundamental assumptions, only that proper care is taken in doing so.

In regards to science, there is a solid bedrock of core ideas, theories, experimental findings, etc., that have all withstood the test of time and repeated experimentation, while out on the edges are the newest crop of scientists who are pushing the envelope, testing new ideas, re-examining old ones in the light of new data, and generally trying to learn more about the natural world.  Out on the fringe, science is indeed in a state of constant flux, and this is a good thing, because it is the only way science can ever progress.  More about this in a moment.  Often the public only sees what is reported through the media, of this-or-that study which overturns this-or-that idea, or contradicts this other contemporary study, and so on.  That is, they only see what is happening on the front lines, and often are unaware of the bedrock.  Or, rather, the bedrock has become so ingrained in common knowledge that it is not even recognized in everyday life as being “science”.  A good example of this is the spheroidal nature of the earth, which (nearly) everyone takes for granted today but was once a far from settled scientific issue.

Its easy to see how folks may get confused and wonder how anyone can trust anything a scientist says at any given moment.  The truth of the matter is, not all science is created equal: some theories are very robust, by which I mainly mean well-attested to by the evidence, while others are far less so.  A contemporary example of the former would be Quantum Theory, while of the latter would be any of the myriad variations of String Theory.  Nevertheless, any theory, no matter how well established up to the present time, is always in danger of being overturned by new data–although more likely, it will not be completely overturned as much as being superseded by a new, more complete theory.  On the flip side, just because a theory doesn’t have a lot of evidence going for it at the present time doesn’t mean it is not a good one that deserves study.  These are two considerations that, in my opinion, make science so exciting to begin with.

So what does progress in science look like in practice?  Most of the time, progress is slow, with small discoveries here and there serving as stepping stones on a more-or-less gentle slope which represents progress within a given theory or paradigm.  A contemporary example would be the continued efforts to understand and refine the Standard Model theory of particle physics–witness the efforts of the teams at the Large Hadron Collider.

Then, every once in a while, a great leap forward is taken.  A classic (perhaps even the archetypal) example of this is Einstein’s two theories of relativity, which together supplanted the reigning paradigm of Newtonian mechanics, almost overnight.  I won’t get into the details of the theories here, but the key point I want to make is that Einstein didn’t as much show that Newton was wrong as he was incomplete. It turns out that Newton’s laws work perfectly fine for everyday circumstances, as long as the local gravitational field doesn’t get too strong or speeds of objects don’t get too close to the speed of light.  Einstein’s theories, however, were able to explain observations of phenomena like the precession of Mercury’s orbit around the Sun which Newton’s Laws utterly failed to do.  (Einstein did so in terms of the geometric warping of spacetime, rather than the unexplained “action at a distance” that Newton’s Law of Gravity relied upon).  Simultaneously, Einstein’s theories explained everything that Newton’s Laws already explained.  In other words, Newton’s Laws are a special, limiting case of Einstein’s theories.  Most assuredly the reason Newton held sway for so long was both because his laws were a very good approximation to relativity, and because our technological ability to observe phenomena that would conceivably violate Newtonian mechanics was limited until near the time of Einstein.  For what its worth, Newtonian mechanics (or classical mechanics as it is often called) is still used successfully by many modern sciences, including my own field of Meteorology, because many fields of science derived from physics don’t have to worry about strong gravitational fields or motions near the speed of light.  (When we discover tornadoes that have winds near the speed of light, I’ll retract my claim!) So, in brief, Einstein built upon Newton, and then leaped beyond him, and his theories are held as the gold standard today not because they are more interesting aesthetically (although they may be that) or that a majority of scientists decided they liked them more, but because they explain more of the actual empirical observations and experimental data that we have access to than Newtons laws do.  I have little doubt that in the future we will find more and more observational “anomalies” that demand an explanation beyond Einstein (there are already some tantalizing hints!), and science will be poised to take another leap forward.  And that’s what I mean by the progressive nature of science.