I’ve started an “Archives” category to archive my numerous debates with creationists over the years. This particular debate started when I mentioned W.V. Quine’s virtue of scientific conservatism (found in his book “The Web of Belief“). I am writing as Johnny, while my opponent, Clete, is a young earth creationist who also prides himself as a philosopher. We enter the debate here when I first mention conservatism.
Conservatism is simply the preference for the hypothesis which requires less rejection of established knowledge. See the example in the post above. Modesty is simply the preference for the hypothesis which includes more familiar phenomenon. For example, that caller who hung up when you answered could be a burglar calling to see if you are home, but a more modest hypothesis is that someone dialed the wrong number. Simplicity is self-explanatory — similar to Occam’s razor.
With respect to conservatism in particular, how do these not tend to maintain and propagate errors of the past? With these as your criterion, once you start down a wrong path, how would you ever do a course correction?
That’s a good question because conservatism can and does propagate errors and I’ll give you an example here in a minute. (I’m finding this hard to verbalize, so please ask for clarifications if I am not clear). In order to understand why conservatism is a “virtue” in science, we have to start way back at the purpose of science. The purpose of science is to approximate the truth, not to dictate the absolute Truth. The way we evaluate whether or not science is approximating the truth is by testing its predictions and descriptions of what we can measure and observe (because we assume that which we measure and observe is true). So assume for a moment we start out with a model that describes a particular phenomenon very well. However, one day some graduate student discovers a particular subset of events within the phenomenon that the model does not accurately describe. There are two choices. We can try to integrate a new model into our old model to form some sort of hybrid model that describes both phenomenon with accuracy, or we can scrap the old model all together because there is some error in it. Because science is trying to approximate the truth, it always choses the option which increases the accuracy. So no matter how many errors are integrated into a model, with each subsequent modification, the model gets closer and closer to perfectly describing reality.
For a good illustration, take a piece of paper on it’s side and draw a circle at one end. At the other end, make a starting point. Now draw a short line in a random direction from your starting point. That’s your first hypothesis. Now you measure the difference between observation / prediction (the end of the line) and truth (your circle). Now draw another line extending from your first line that more approximates the direction of the truth circle. And then another from that line. The idea is that by conserving that which is established and integrating new ideas, you maximize your descriptive powers and you move closer and closer to the truth even if there are some errors in your lines. This is considered superior to completely scrapping a line very close to the truth circle because it does not hit the circle directly (non-conservatism).
Now, some times bits and pieces of models have to be chopped out to help integrate new ideas. But so long as these modifications move a model towards better description, this is acceptable. Other times, two models are completely incompatible. In this case, it usually takes a few decades of research before one model emerges triumphant over another.
I hope I explained that well, I can’t remember for the life of me how it was explained to me, and the books I have dealing with this topic are back in Florida at my parents house.
Based on Johnny’s answer to this question, it would seem to me the conservatism in science is only virtuous if one has it in mind not to rock the boat too much. Any theory which describes a fundamental paradigm shift would automatically be rejected regardless of its power to explain observed phenomena.
…I understand that extraordinary claims require extraordinary evidence, if for no other reason than that those who need to be convinced are entrenched up to their necks in the uniformitarian paradigm. Paradigm shifts always present a great deal of emotional and intellectual inertia and it seems clear to me that this conservatism criteria is designed to reinforce that inertia. Not very useful in a pursuit of the truth if you ask me. Our first duty should be to the truth, not to the scientific status quo.
I don’t think you fully understood my answer (likely the issue was with my explanation). It’s not the case at all that fundamental paradigm shifts will be automatically rejected based on conservatism. It just means that new paradigms must meet at least the standard of evidence the old paradigms meet. Any new hypothesis worth it’s weight will be evaluated against current knowledge. If it is possible to integrate a new hypothesis within the model of current knowledge to yield more accurate descriptions, then why would you not consider this superior to rejecting the former model outright? If we reject the former model outright we are left with no model, no description, whereas if we integrate two models, we are left with a closer approximation of the truth. If two models cannot be integrated, then one will eventually topple. Conservatism says that it is most probable hypothesis is the one with the most evidential support. However, it does not ensure this conclusion by any means. And so new hypothesis which contradict existing knowledge must have significant evidential support to be considered a serious contender against a better supported hypothesis.
In fact, the principle of conservatism is intuitive . You and I use it in every day life when making every day decisions. We use it when we read the Bible, and scientist use it when they do science.
Here’s an example:
We have been measuring the gravitational constant on Earth for several hundred years with dozens and dozens of different methods and by thousands and thousands of scientists with ever increasing accuracy. Today, I got on my scale and the scale told me I weighed 75 pounds. Yesterday, my scale told me I weighed 170 pounds. I now have two things to consider.
Hypothesis #1 The gravitational constant is wrong and has been measured wrong for 2 centuries.
Hypothesis #2 My scale is broken.
Established observation: The gravitational constant is 9.8m/s^2
Conservatism says that it is much more probable that my scale gave an inaccurate reading than it is that the gravitational constant has been measured wrong all those years. Thus, integrating the models: the gravitational constant was measured right AND my scale is broken. The integrated model produces a closer approximation to reality and explains both phenomenon while preserving the established observations.
Conservatism is a foundational principle of the philosophy of science, and it works the same in physics as it does in origins science. Conservatism does allow for the integration and assimilation of errors at times (see Newtonian physics), but here is the key: Any true error in a description of a phenomenon must manifest itself as observation given the right conditions (otherwise, by definition, it is not an error). For this reason, any true error will eventually manifest itself given that we , and when it manifests itself it will be corrected.
Conservatism is the very strength of the scientific method. It is in this principle that science moves continually towards closer and closer approximations of the truth. It demands the highest standards of evidence for competing hypothesis, and thus we can have confidence when established descriptions are eventually overturned in favor of newer descriptions.
Like I said, it’s very intuitive — I know at first the integration of errors seems like a drawback, but in fact it’s a strength. If we reset every time we found a mistake we’d still be at square one, because ultimately our best descriptions are going to fall short. We cannot observe all phenomenon and see all physical states, and thus our confidence in our science is as strong as what we can measure. Thus, conservatism gives us a backbone on which to move forward with descriptions, moving ever towards the goal of the “perfect description”.