Theory Evolution (not "Theory of Evolution")

I'm not sure why you see this a problem. Kuhn perhaps overstated things here, but then largely corrected the overstatement in his 1969 postscript (at the back of the 1970 edition). As a critic of falsficationism, I don't see this as a problem in Kuhn's work. Kuhn was not anti-science. He was criticizing the traditional epistemology assumed by philosophers of science. He was not criticizing the science itself.There is a good reason why creationists rarely use Kuhn in their arguments. For creationists are themselves pretty strongly committed to the kind of epistemology that Kuhn criticizes. To adopt Kuhn's critique, they would have to admit to problems in the epistemological assumptions that underly their own theology.

Your mistake (IMO).There are several ways of looking at a scientific theory.

We can look at the equations. From this perspective, it does look progressive.

We can examine the metaphysics. Here it is clearly not progressive. According to Newtonian metaphysics, there is an occult force of attraction between any two masses, and the geometry of space-time is euclidean. According to GR, there is no such force, but space-time is non-euclidean and gravitation is explained as due to local curvature of space-time induced by the mass.

We can look at what typical observation statements say about the world. And again, what they say under Newtonian physics is quite different from what they say under relativity, and the change is non-progressive. Under Newtonian physics, the basic concept time is a reference to a univeral property, while under relativity it is a reference to a property which is relative to the frame of the observer.

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Each incorperated the former into the new paradigm, so I don't see how they are incommensurable.

It seems that way to you, because you are always assuming GR. But you have to examine these theories according to their own standards.

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To say that an object is 1 metre long in Newtonian physics, is to say that if I take it to Paris, and compare to a famous platinum rod, then its length exactly corresponds to the marks on that rod. To say that an object is 1 metre long in GR is to say that it will take a certain number of ticks of a portable atomic clock for light to traverse from one end to another. These clearly mean different things. That's where the incommensurability comes in.

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Granted the differences are slight with respect to our ordinary lives. But they are differences nonetheless.

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Also, it seems that we cannot say theories are ever false with his view. They are simply incommensurable with modern theories. I think we are actually removing the chaff, not just switching our rules for which to interpret the world.

That's fine with me. It is at least honest.

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I'm not sure that "our rules for which to interpret the world" is actually meaningful. We interact with the world, but I don't see that we interpret. We make measurements of the world, and we interpret those measurements. But the world is not our measurements. The world is what we are trying to measure. And we certainly do change the rules by which we measure the world, and we correspondingly change the rules by which we interpret those measurements.

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Keep in mind these are my opinions.

Of course. If there were no disagreements, we wouldn't have interesting debates.

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So, as a critic of falsificationism, are you a verificationist?

Not in the form that verificationism is usually presented.

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As I see it, a scientific theory is neither true nor false. We judge scientific theories on pragmatic grounds, not on veridical grounds. That is, we want theories that work well (as in making good predictions), and we are not interested in theories that don't work.

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Maybe that doesn't sound too different from Popper's philosophy. But the difference is that there is no convincing evidence that accepted theories are declared false on the basis of failed predictions. The evidence is that accepted theories are rejected only when a better replacement theory is available.

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Roughly speaking, we evaluate theories on goodness of fit, not on truth or falsity.

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Maybe there is a different way to put it. If you believe that we evaluate scientific theories in terms of their truth or falsity, then you owe me a comprehensive theory of truth such as would make it possible to determine whether a theory is true or false.

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How do we distinguish scientific theories from crack pot theories?

Crackpot theories do not make good reliable empirical predictions.

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Why is an explanation that can handle all observations (explain everything and anything)not science?

Okay, I'll be a heretic here. I don't believe that a scientific theory is an explanation. It might include explanations, but explanation is not the main point as I see it.

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The traditional view takes for granted that concepts (time, distance, temperature, electrical current, electromotive force, etc) exist a priori, and scientists just discover relations between these interesting concepts. My view, which I think well supported in the history of science, is that concepts are human inventions. We invent these concepts so as to make it possible to describe the world. In practice this shows up in physics as the invention of coordinate systems and systems of weights and measures.

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I see a scientific theory as carefully defining important concepts such as are needed to describe the world, and setting standards for measuring the quantities associated with those concepts. Thus what is important about science is the way that it makes it possible to have precise descriptions of the world. The most important part of a scientific theory is in the new concepts it introduces and the methods it defines for measuring quantities represented by those concepts.

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But, he was a science antirealist.

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This is related to the perennial philosophical problem of universals. If a tree falls in the forest, and there is nobody to hear it, does it make a sound. It is the question of whether the concept "sound" exists as a real property in the world, or whether it is a human invention needed to make it possible for us to express statements about the world.

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I see it as obvious that a property such as "sound" is a human invention. History shows people inventing such concepts, or reinventing them with slightly different meanings. Now maybe we can say that they are real, and when we invent them we reinvent something that already exists. That's fine with we. It doesn't matter much whether we consider them real or invented. It is clear that such concepts are being invented, whether or not they are real.

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The important part, to me, is that

description is impossible without concepts;

we invent concepts so as to make description possible;

when inventing concepts, we set standards (or rules) for how to apply those concepts in the real world;

these standard (rules) form the core of our scientific theories.

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Creationism is largely a reaction by fundamentalist Christians to the views that science is teaching. If it is realized that scientific theories aren't true or closer to being true than any other explanatory framework, they should have nothing to worry about.

This doesn't work. Let's go over it again.

It is impossible to make any statement about the world without first having a suitable system of concepts;

science sets the standards and criteria for using the basic concepts (those used to describe the world);

the truth of a statement about the world is judged in terms of those standards and criteria set by science.

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If creationists want to say things where science cannot judge their truth, then they need to have their own separate concepts. To some extent they already do that, as when they use "kinds" rather than "species" in their criticism of evolution.

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As long as the scientific system of concepts, weights and measures works well and makes generally reliable predictions, while the creationist system of concepts works poorly or not at all, the creationists will have difficulty in having society adopt their system.

Hmm. I will have to think about that. Thanks for the comment.

Sure it has.However, the "Is it science" forum, and this particular topic, are for discussion of issues related to the methodology of science. What you perceive to be problems in the theory of evolution should be discussed in other threads, not here.If you have points about scientific methodology, and can use evolution as an illustrative example, maybe that would be suited to the current thread.This message has been edited by nwr, 12-10-2005 01:34 PM

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What shall it profit a nation if it gain the whole world, yet lose its own soul.
(paraphrasing Mark 8:36)

I'm not sure how physicists talk about it. If you were in free fall, then you would not see other objects around you as accelerating.If you want to say it is a force, it would seem to be something analogous to centrifugal force which most physics texts say does not actually exist. Rather, they prefer to say that there is centripetal force, which keeps things in circular motion and resists movement in the path the object would naturally take.Even if people refer it to a force, it would not be an attraction between masses, but a force due to the curvature of space-time. "Incommensurability" is Kuhn's term, so we are stuck with it. If I were picking terminology, I would prefer "concept change".I first heard the term "incommensurable" in high school mathematics, where we learned that the diagonal of a square is incommensurable with the sides of the square, due to the ratio being irrational. This indicated that logic, together with the ruler-compass methods of Euclidean geometry, could not get from one to the other. I take "incommensurable" only to mean that there is not an exact logical translation from one to the other. That you can get very close approximations would not seem to contradict incommensurability.But then I'm a mathematician and computer scientist, not a philosopher. So I don't really know how philosophers want to use these terms. Newtonian mechanics is a limiting case of GR from the point of view of the mathematics and the methodology. The change to GR is a total upheaval from the perspective of its metaphysics. Copernican astronomy is mainly a changed in coordinates from Ptolemaic astronomy, when considered from the perspective of the mathematics and methodology. It is a total upheaval in terms of its metaphysics. J.B. Priestley developed some pretty good predictive empirical science on the basis of phlogiston, leading to Lavoisier's discovery of oxygen. In terms of the mathematics and methodology, the change from phlogiston to oxygen is quite small. We make phlogiston the butt of science jokes because we reject its metaphysics.Personally, I am an agnostic with respect to metaphysics. It is clear that Kuhn took metaphysics to be the main thrust of science, and that's why incommensurability, and his comments about living in different worlds, seemed to Kuhn to address the important issues.The change from Aristotlean science to modern science is profound, not so much because of the change in mathematics and metaphysics, but because of the introduction of systematic empirical methodology. It provides the theoretical framework under which we develop measurement conventions. I doubt that. We don't perceive X-rays, but I suspect that you consider them to be part of the world. What we mean by "world" is a complex issue, and perhaps best left for some other discussion. That makes the rejection of a theory a matter of declaration, rather than a matter of its truth or falsity. It is considered false, only because we declare it so. I don't have any particular problem with that.We are quick to declare proposed theories false. In some cases we may later accept them as true, after originally declaring them false (roughly what happened with plate tectonics). But what about an established theory? Is an established theory ever declared false before there is a successor theory available to replace it? I cannot think of any examples where this has happened. No, that would not be my view at all. In any case the analogy is bad. But pretending that it is similar, the conclusion would only be that we cannot conclusively prove guilt. We can prove guilt beyond a reasonable doubt, but not beyond all doubt.You seem to be taking me as opposed to science because it does not provide conclusive proof. That's not my position at all. I'm a pragmatist. I see "absolute truth" as a myth. We do our best to thrive in this world, and our science is part of how we do this. We need not be concerned with whether they provide absolute truth (or metaphysical truth). It suffices that they work very well, and that they work better than the alternatives that we have tried. Keep in mind that I am agnostic with respect to metaphysics, and therefore I am agnostic with respect to the existence of metaphysical truth.

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What shall it profit a nation if it gain the whole world, yet lose its own soul.
(paraphrasing Mark 8:36)

You may have misread that.As I read it, this topic is about the fact that theories evolve, about how they evolve.It is also about how some religious groups appear to be confused by the evolving of scientific theories. Apparently some religious groups see change in scientific theory as evidence that the science is wrong, while most scientists see it as evidence that the scientific method is converging toward providing a true account of the natural world.

He took that from history. It was a consequence of the Newtonian concept of time, that you could talk of the simultaneity of events. The relativistic concept of time ruled that out when events occur in different inertial frames. Quite a few physicists found it difficult to accept this change.Kuhn overstated the problem. People do learn to translate between statements made under one conceptual framework, and those made under another. We had to change our ways of thinking about the world. No. Some change is just a refinement. Mathematically, the change from Ptolemaic astronomy to Copernical astronomy is simply a change of coordinates. The ptolemaic system used polar coordinates with the earth as center, while the copernical system used the sun as the center. Mathematically, this is a simple transformation.I'm not much of a student of history. Those who are say that Copernicus avoided problems with the Church by emphasizing the mathematics, and not insisting on a changed metaphysics. Galileo did insist on a changed metaphysics, and ran into a serious dispute.Granted, it is easier to think about the solar system if one makes the change in metaphysical assumptions. But it seems clear that the mathematics and metaphysics can be separated if one wishes to do so. I agree with you on that. I don't know what "metaphysics" means either, I'm just pretending that I understand it. As best I can tell, metaphysics has to do with the way the world really is, independent of human perception and observation. I suppose it is something like a God's eye view of the universe. It is what it would look like to an observer standing outside the universe.Keep in mind that I'm making this up as I go along. Anyone who really knows what "metaphysics" means is invited to step in and correct me. It is my impression that there is no generally accepted metaphysics of QM. The various interpretations are attempts at providing a metaphysics. I see no important disagreements in those parts of your message, so I won't further comment. Science often creates new concepts, new kinds of information. Criminal investigation is usually based on existing concepts and existing measurement tools. Where it does create new kinds of information, it often fails to test this with the thoroughness of science. We are seeing this now in the case of fingerprints, where scientific investigation is showing them not nearly as perfect as criminal investigators had assumed them to be.As for inductive logic, I suppose it depends on what is meant by that term. Lots of things are said to be inductive logic, but aren't. As described by philosophy, inductive logic is exclusively based on using existing concepts. Where the science is based on the use of new concepts, it cannot be merely inductive logic.What typically happens in a criminal investigation is that there is partial evidence. Then a case is built on interpolation and extrapolation from that evidence. Perhaps that counts as inductive logic. You can call that "goodness of fit" if you like. There is uncertainty, due to the use of interpolation and extrapolation. However judgements of truth or falsity, admittedly using uncertain data, are still based on well accepted criteria for assessing truth.Science often introduces completely new concepts and new ways of measuring. It makes predictions based on these completely new concepts. So that is using a very different notion of "goodness of fit". When you introduce new concepts, there are no well accepted criteria for assessing the truth of accounts that use the new concepts. Take your time. There is no hurry.