Re: Fw: Scientific theory

Something I have recently written on scientific method which some may recognise
Michael

Thus we need a definition which includes a broad understanding of contemporary science and one which allows for changing views of science during throughout history. So what is science and what to scientists do?

I will begin by giving some of my family history. We go first to a small chemistry laboratory on the roof of Butler's Wharf Bridge on the River Thames overlooking London in 1960. A biochemist works there on the chemistry of tea. The labs are full of glass apparatus and he is isolating and identifying unknown chemicals from tea - theorubigen and theoflavins and lots more theo-s. This is science, he is doing repeatable experiments, as the biochemist first isolates the compounds and then works out their molecular structures. After his work is published others can test his work. Now let's go to the Namib Desert in South Africa in 1970. The son of the biochemist is making a geological map of a few thousand square miles for a mining company and prospecting for base metals. Every day he goes out and works out the order of stratification and marks them on his map. He identifies conglomerates, sandstones, lavas, limestones and tillites and estimates their thickness. He works out the historical order in which the rocks were formed and draws up a geological column and says that the tillites are the newest rocks and the gneisses under the conglomerate are the oldest. From a few radiometric dates made by researchers in Cape Town he ascribes tentative dates to the rocks. He records any mineralisation. He observes and records but does no experiments, as geology is a historical science. Is this science then? He was very annoyed when his uncle, a physics professor turned clergyman, asked him a few years later if all his geology was stamp-collecting, as if physics were the only true science. Twenty-five years later the geologist does a field project on the hybridization of Red and White Campions in Provence and records the shape of leaves, color of petals and the shape of calyxes. This is observation and interpretation but no experimentation. Is this science? The biochemist was my father and the son myself.

This is science in my family but ask yourself, "Which of these four activities is the most scientific?" Is it Chemistry, Physics, Geology or Biology? It would be very dangerous to favor one or the other, but these sciences are different and have overlapping understandings of science and at times have different methods.

There is Experimental Science where a researcher artificially selects something to test under controlled experiments. This is what my father and uncle were doing in their biochemistry and physics. Then, much of science is Observational, especially the earlier and classic forms of natural history, mineralogy and astronomy. These depend on detailed observation, classification and measurement. This I did in my project on Campions. There are the Historical sciences, which attempt to work out the historical order of past events. Geology and paleontology are classic historical sciences, and that was my main scientific discipline. Within all these is Measurement, in which some kind of mathematical approach is used to order the subject matter being studied. This may be anything from simple counting to the most complex calculus.

There is one major difference between Historical sciences and the Experimental and Observational sciences, and that is the former deals with non-repeatable events in the past, and the latter with potentially repeatable observations. These latter two aspects of science are sometimes termed operational science. As operation science deals with repeatable events, others can therefore test these by repeating the procedures. They also give rise to predictions from what has been discovered by those scientific procedures. I will give an example from my project on Red and White Campions. In Britain, which has a wet climate, I found they hybridized freely, but in Provence (France), which is fairly dry, they did not. From that, and other reasons, I predicted that at Mont Dore in the Auvergne, which is wet, they would hybridize. My prediction turned out to be correct, which gave support, but not proof, for my theory that hybridization was related to climate. Unfortunately I did not pursue my study. To give another example, as I write (May 2004) the transit of Venus is due to be visible in Lancashire in June, where it was first observed by Jeremiah Horrocks in 1639. From previous astronomical observations and his own calculations, Horrocks had predicted that the transit of Venus should be visible on 24th November 1639 and that it was in agreement with an elliptical orbit predicted by Kepler. As his predictions from his observations and calculations were proved correct this gave further confirmation of Kepler's laws.

At times, some have questioned the reliability and philosophical soundness of historical sciences like geology on the grounds that they do not deal with repeatable events (what's history is history!) and one cannot make predictions. The doubts have been expressed as follows;

Most sciences, including chemistry and physics, are empirical (or experimental) in nature; theories can be tested by experiments in the laboratory and/or by observations of the world. Some disciplines, like origins science, are historical in nature; that is, they attempt to explain events and processes that have already taken place in the distant past. Theories in historical sciences cannot be verified experimentally, so the explanations are always tentative.

At first sight, that sounds very convincing, but it contains several flaws. First, it implies that the ultimate in science is experimental thus ignoring observational science. The statement is confused over this. It has not clarified what historical sciences are, but by saying that "Theories in historical sciences cannot be verified experimentally", it expresses a dangerous half-truth. Of course, one cannot test most geological ideas experimentally - e.g. whether T Rex could run at 20 m.p.h. or could only trot, or whether the direction of the Precambrian rivers in the Stinkfontein Formation in South Africa flowed towards the west, as I found from the measurement of cross-bedding in the sandstone. Neither can one make predictions for the future. However theories in geology can be tested rigorously and to a considerable degree of certainty. Much can be worked out about T. Rex from comparative anatomy - using the same principles that a human anatomist would use in identifying the age and sex of a human skeleton. From the study of the Stinkfontein sandstone, especially of its cross-bedding and grains of sand, a geologist would not make a prediction but a retrodiction and suggest that in that period of time (1000 m.y. ago) there was a source of the sand to the east and that these older rocks were very rich in quartz and were probably either quartzites, gneisses or granites. In fact twenty miles to the east these Stinkfontein rocks lay unconformably upon older rocks, which were quartzites and gneisses of the Kheis. Geologists perform these "tests" on their work continuously and when, as happens often, they are wrong, they have to revise their theories, which in turn are tested. Now geology is about 250 years old as a science, and theories have been tested rigorously in that period, so that much of geology is now certain not tentative.

When practiced properly, all these different scientific methods have great rigor as there is a careful methodology but they also need theory, which is very different from speculation. There is a popular misunderstanding that theory means something abstract and unproven, whereas to a scientist a theory is what interprets their data and seeks to make sense of it. The theory changes as further research is carried out.

We need to be aware not to separate scientific fact from scientific theory and regard the second of limited value. In fact we cannot separate fact from theory as whatever a scientist does is based on theory. For example, in the early 19th Century the main theory guiding geology was that the Deluge of Noah had tremendous geological effects. Thus when the greatest diluvial geologist William Buckland went to Snowdonia in North Wales in 1822 he observed great mounds of sediment and scoured and rounded dome-shaped rocks (roche moutonee). He said the mounds were deposited by the Flood, which also scoured the domed rocks. He returned in 1841 after Agassiz had convinced him of the ice age. (Figure 1.) This time he said the mounds were moraines deposited by glaciers and the domed rocks were caused by the abrasive action of glaciers. In fact, for years his diluvial theory stopped him from seeing many geological structures caused by ice.

Science has not been an unchanging study of the material world and Scientific Method has not remained constant over the centuries. We should not speak of THE Scientific Method as today there are many Scientific Methods and these have changed over time. At the risk of over-simplifying, in the Ancient World the emphasis on scientific method was on observation, classification and measurement rather than experiment as we know it. This outlook continued until the mid-16th century when Copernicus almost unwittingly began the Scientific Revolution.

One of the results of the Scientific Revolution Experiment was to play down the authority of learned tradition. During the period 1500 to 1700 there was a diminishing respect for authorities for their own sake and a greater recognition of primary observation and experiment. By the end of the period scientists would no longer defer to the authority of an Aristotle or a Galen only because of their status. Their opinions had to be demonstrable. Galileo was one of the first to challenge ancient authorities if their statements could not be verified. This represented a marked break with tradition, but even into the 19th century scholars from the humanities still deferred to ancient authorities whether of antiquity or a previous generation. At times they were hostile to the methods of scientists.

The effect of the Newtonian Age was to consider that Experiment was the most important scientific method and that anything else was inferior to it. That prejudice is still prevalent today both in popular and academic circles. As a result it is easy to downplay the importance of descriptive biology and the rise of the historical sciences, such as geology and paleontology in the 18th and 19th centuries. This chauvinism of the physicists is to be seen clearly in Lord Kelvin's disparagement of geologists' estimates of time in the late 19th century, as we will see below.

  ----- Original Message -----
  From: Jim Armstrong
  Cc: asa@calvin.edu
  Sent: Monday, December 13, 2004 8:52 PM
  Subject: Re: Fw: Scientific theory

  But Randy, I'm not quite in accord with what you've said here, but for sure that last sentence just doesn't seem to be the case. The creationist discussions concerning geology, for instance, are rife with falsification arguments. Absence of evidence is cited as falsification. Exceptions to the generally found ordering of sediment/fossil layers comprise falsfications. The discussions of the Grand Canyon geologic structures may be where it is most evident [try googling falsification and "Grand Canyon"], but there are certainly many others. The problem is what constitutes falsification to one person is a simple anomaly to another, the difference being how one regards the evidence that is the object of falsification.
  JimA

  Randy Isaac wrote:

    I fully agree, Don. That's why I focused on "falsifiability" rather than "proofs" or "verifiability". In science falsifiability is usually the operative word. Neither test will prove evolution--that comes in growing acceptance based on the combination of many types of evidence and absence of falsification. In these tests, a counterexample would falsify evolution. In contrast, a creationist who rationalizes the results in the manner you indicate, would not count a negative result as a falsification.
    Randy

    ----- Original Message -----
    From: Don Winterstein
    To: asa ; Randy Isaac
    Sent: Friday, December 10, 2004 4:04 AM
    Subject: Re: Scientific theory

    Randy Isaac wrote:

    "I think that out of a number of tests [of the theory of evolution], there are two that I find striking:
    1) the theory of common descent predicts that all living organisms have DNA based on the same four, and only these four, nucleotides.
    2) it also predicts that all naturally occurring DNA will have the same (left-handed as it turns out for unknown reasons) chirality."

    I'm going back to this because, if you use these arguments as significant "proofs" of the theory of evolution, you at least need to be aware of the questions you are begging. Since no one with more competence in the field has addressed this, I take on the responsibility.

    Test 1 (four nucleotides) would be meaningless unless DNA could function with different nucleotides than the known four. But nobody knows this. Given all the churning of genetic codes that must have gone on over the billions of years, it would be surprising if no instances of different nucleotides ever occurred. If they haven't, a likely implication is that DNA can't function with different nucleotides. If so, DNA of all organisms would have the four nucleotides whether or not all organisms had a common origin.

    The chirality result (Test 2) is harder to argue against on this basis. However, if life originated only a few times, chances of starting with the same handedness in every case would be pretty good, so handedness still would not necessarily imply a common origin.

    These predictions address the question of whether all life had a common origin. But if we extend the question into the theological realm, which we like to do, then satisfaction of neither prediction is necessarily of any value: For example, a creationist who believed that different life forms were specially created at different times could say that (1) God determined beforehand that DNA with the four nucleotides was the preferred solution and (2) God likes left-handed rotations.

    I claim it's difficult or impossible to make a good case for evolution purely on the basis of DNA. Without the fossil evidence, such arguments would merely generate breeze. They have limited merit because there is fossil evidence.

    Don

      ----- Original Message -----
      From: Randy Isaac
      To: asa@calvin.edu
      Sent: Tuesday, December 07, 2004 6:19 PM
      Subject: Re: Scientific theory

      "Not to argue with you, Randy, as I believe in evolution in a Christian
      context, but can you discuss a test of the theory of evolution which it
      has passed, thus demonstrating for all to see that it has been
      scientfically proven?

      Thanks,

      --Bill Yates"

      I think that out of a number of tests, there are two that I find striking:

      1) the theory of common descent predicts that all living organisms have DNA based on the same four, and only these four, nucleotides.
      2) it also predicts that all naturally occurring DNA will have the same (left-handed as it turns out for unknown reasons) chirality.

      To my knowledge, no instance has been found that violates either one of these. And I don't know of any other theory of origins that would make the same definitive prediction, though one might rationalize why it should be so. No, Darwin didn't know about DNA structure so this prediction came later, but there's an incredible amount of data that's been collected since DNA was discovered and it all seems to fit--so far.

      I'm not saying whether I believe in evolution or not. But let's not reject it on the grounds that it isn't scientific or that it isn't testable.

      Randy
Received on Mon, 13 Dec 2004 23:16:57 -0000