Tuesday, October 10, 2017

Scientific Theories Change: So how can science be trusted? (and comparison with biblical interpretation)

Often when I give a public talk about science and Christianity at a church or other Christian venue someone will make a comment that the theories developed by science are constantly changing so they cannot really be trusted. I believe that the person making such a statement may often have an underlying assumption that some of the conclusions of science, usually the Big Band and/or evolution, contradict biblical teaching and so those theories really can't be believed or accepted. Similarly, I have heard Christians claim that the theories of science are fallible since they are developed by humans, while the Bible is infallible since it was given by God. As a scientist, I have a lot more confidence in the scientific conclusions drawn from the observations than some people who might make statements like that. Consequently, I think it is important that people understand something about the scientific process and why the findings of science can be trusted. As a Christian, I think it is crucial to distinguish between the infallible Word of God and the fallible interpretation of that word by individual humans. This post will cover some of these subjects and then go on to discuss why I believe there is quite a bit of correspondence between how to interpret the facts of nature and the words of the Bible.

As many scientists have pointed out, one of the strengths of science is that theories can change as more data is gathered. Any search for "truth" must be willing to change conclusions based on new observations or facts. If the scientific endeavor has any validity then we would expect some theories and conclusions to change as new observations are made. However, when something is very well established based on experimental evidence, it is unlikely to be completely overthrown. In that sense, science does not change and the conclusions are solid. For example, consider Newton's laws of motion which were first published in 1687. For centuries experiments confirmed their validity until the early 20th century when more precise experiments showed that Newton's law are just approximations of more fundamental laws of nature and that Newton's laws completely break down at very small distances and at very fast speeds. So what do we do with Newton's laws? Discard them? Not at all. We still teach his laws in every introductory physics course as foundational to our understanding of nature. They are applicable in most macroscopic circumstances so they remain worthwhile to teach. The lessons to take from this can be be generalized to other scientific studies: (1) Laws that have been overwhelming established by experiment may be refined and shown to be limiting cases of more general principles but they will not be deemed as completely erroneous. (2) It is a positive development when we uncover deeper principles of physics that refine our previous understanding of nature. So although science does change when new observations are made and new experiments are done, the facts that have been well established by multiple experiments can be trusted as valid, even though they may be refined in the future. Scientific conclusions can be trusted.

The above principles are applicable to the Big Bang. The evidence that our universe was extremely hot and dense and has been expanding for the last 13.8 billion years has been firmly established. There will be developments and observations that refine this theory and maybe even show it is a subset of a more generalized theory, but it will not be overthrown. Those who use the changeability of scientific theories as an excuse to doubt the veracity of the Big Bang are probably misguided in their opposition to the Big Bang and misinformed regarding the strength of the evidence for the Big Bang.

As a scientist and a Christian, I have also observed that principles of good biblical interpretation have much in common with principles of good scientific inquiry. Here are some parallels:

Biblical Interpretation Scientific Inquiry
1.  Human attempt to understand the Bible. Human attempt to understand nature.
2.  Has well developed principles for how to determine what is true. Has well developed principles for how to determine what is true.
3.  Any practitioner should follow these principles. Any practitioner should follow these principles.
4.  There is a large body of knowledge accepted by the experts. There is a large body of knowledge accepted by the experts.
5.  Some things not agreed on by the experts.Some things not agreed on by the experts.
6.  Has some well established truths that will not be discarded though may be refined. Has some well established truths that will not be discarded though may be refined.
7.  Our understanding can change with new facts. Our understanding can change with new facts.

I think this list is important because I hear claims from Christians and from non-religious scientists that seem to show a misunderstanding of the processes used in these two disciplines to determine truth. I actually notice many similarities in the respective disciplines, although such a statement might not be embraced by either my scientific colleagues or my theologian friends. The above parallels are true even though a Christian may be guided by the Holy Spirit when trying to understand the Bible. (Of course a Christian scientist could also be guided by the Holy Spirit when trying to understand nature, as well.)

Should Christians, in general, trust scientific findings even though future observations may modify the conclusions? I think they should.  In the same way Christians should trust their understanding of the biblical text but be willing to consider possible modifications based on new findings. The discussion should not be framed in terms of man's interpretation of nature vs. God's infallible word, but rather man's interpretation of the facts of nature and man's interpretation of the words of the Bible guided by the Holy Spirit. In general, human interpretation of nature and of the Bible may not be completely correct and should have flexibility to be modified as new observations are made.

Christians will often state that God is the creator of nature and he is also the author of the Bible so there should be no discrepancy between the two. However, some then go on to dismiss major findings of science which, in my opinion, reinforces the belief that there is really a large chasm between science and Christianity. In contrast I believe that the common features listed above can serve as a foundation to build a bridge between scientific findings and biblical statements. I'll elaborate more on that in my next post.


  1. Mike, Intriguing post for sure. One extension would be to illustrate departure from best practices for each discipline. Perhaps medicine best illustrates the efficacious nature of change. No one wants to return to diagnosis methods prior to germ theory or restarting bleeding.

    I do have issues with science when it goes off on a tangent as in string theories or multiverses where not even experimental methods of observation can be effected. And while I start from the plain language approach I also get it...the scriptures are replete with non-literal tools of literature so care must be taken.

  2. Dr. Strauss,
    Science, since it was born out of Christianity, and even offers much evidence in support of Christian claims, 'should be' one of the Christians best apologetic resources. Yet, atheists, in their attempt to hijack science from its Theological moorings, have falsely tried to claim that science and Christianity are at odds. This has been going on for a couple of centuries now and is referred to as the 'warfare thesis'. It is a false revisionist history.

    The Two Guys to Blame for the Myth of Constant Warfare between Religion and Science - February 27, 2015
    Excerpt: Timothy Larsen, a Christian historian who specializes in the nineteenth century, notes:
    The so-called “war” between faith and learning, specifically between orthodox Christian theology and science, was manufactured during the second half of the nineteenth century. It is a construct that was created for polemical purposes.
    No one deserves more blame for this stubborn myth than these two men:
    Andrew Dickson White (1832-1918), the founding president of Cornell University, and
    John William Draper (1811-1882), professor of chemistry at the University of New York.

    In my latest video, the atheists' attempt to falsely define science as being confined solely to 'methodological naturalism', and the failings of that 'confinement', are discussed.

    A Critique of Methodological Naturalism and Natural Selection - video

    1. You are totally correct. Much of Andrew Dickson White's book is no longer considered valid by modern historians, yet his thesis remains and many people accept it despite the fact that it is grounded on much that has been discredited.

    2. Wait... he opens with the patently false claim that "science... was born out of Christianity..." and your response is "You are totally correct"?

      I wish I could say I was surprised.

    3. See what actually historians say about this in articles like http://blogs.nature.com/soapboxscience/2011/05/18/science-owes-much-to-both-christianity-and-the-middle-ages. Yes, the development of modern science occurred in a Christian culture where early scientists thought they were learning about an intelligent and rational God.

  3. Before claiming the scientific method has a problem because scientific theories changed, first one should evaluate if how the changed scientific theory was determined as correct in the first place. Perhaps the scientific method wasn’t properly applied in the first place such as some speculative assumptions were made or all the possible alternative explanation were not ruled out. Fundamentally what should be critiqued are the basic criterion and principles in the scientific method.

    “Rational Reasoning for Reality” found at my webpage https://sites.google.com/site/s2hinrichs/home explains principals used in the scientific method. A basic criterion and principles in the scientific method is the use of the process of elimination with a goal to perhaps get to the point of eliminating all possible explanation except one implying the one remaining must be true. Use of this principal involves critical thinking where basically one does everything they can do to prove a theory wrong. It is not until after this is done that the scientist considers claiming the theory is correct. It makes sense before believing something is true to do your due diligence to check if it is false. Often people will tend to just build up defenses for maintaining their personal beliefs, rather than rigorously investigating if they are false.

    Fundamentally the scientific principal do not assume there is no supernatural; however, according to Okman’s razor the theory with the least presuppositions is preferred; thus, naturally it is assumed the supernatural did not intervene unless shown otherwise.

    Personally I do have a preference that God exist, so I do have a bias in believe the supernatural exist. However, for a religious person who respect science, I think they would follow this guideline for their religious beliefs or for any belief. For anything theory for which according to science there is strong and solid evidence that it is true, all of one’s beliefs must be consistent with this theory. One should not believe anything theory for which according to science there is strong and solid evidence that it is false.

    1. You are correct in that many of the scientific "theories" that changed didn't have any real observational evidence to back them up in the first place.

  4. Interestingly in The Road to Reality the author states that Popper's proposal or axiom that a valid theory must have a way in which it can be falsified is too stringent and not applicable in the current state of cosmology and its mathematical underpinnings. Is the original axiom grounds for dismissing a theory which is the definition of a change.

  5. Well said Dr. Strauss. Thank you for continuing to writing this blog. I didn't know you spoke at churches as well as universities about this stuff (I've only ever watched youtube videos from university seminars). I think both are invaluable public services. Thank you for that too. The need for both is impossibly important today.

    1. Based on your comment, I have added a new tab to my blog with my speaking schedule. I'll try to keep it updated as much as possible. I won't post venues that are not open to the public like high schools which I do a lot, but you should see a variety of universities and churches, at least several times during the year.