NATS 1700 6.0 COMPUTERS,  INFORMATION  AND  SOCIETY Lecture 1: The Method(s) of Science  I : Introduction | Previous | Next | Syllabus | Selected References | Home | | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 |   Introduction A good reference for the first part of the course is  A F Chalmers, What is This Thing Called Science?  2nd edition. University of Queensland Press, 1976, 1982. The Introduction and Chapters 1-3 are particularly appropriate for this and the next lecture. However, most modern books on the nature of science should do just as well. The question whether science is a unique European phenomenon is addressed, for example, in an article by Ziauddin Sardar on the New Scientist Magazine (Bright Sparks, 21 October 2000, issue 2261), where the author argues that "passion for science isn't restricted to the richer countries of the West. If people think otherwise, it's because colonialism did its best to stamp out every last vestige of indigenous research in the East." A useful summary of the traditional concept of scientific method is that by Jose Wudka (UC Riverside) in his course  Physics 7.  Read carefully, and try to identify the weak points in Wudka's definitions and in his arguments. You may also browse through an interesting article by Margaret Berger,  Expert Testimony: The Supreme Court's Rules,  which examines instances of the Court's requirement that the scientific method must be used in order for an expert witness’ testimony to be deemed acceptable. See also Admissibility of Scientific Evidence under Daubert . There are many other examples of social institutions embracing the scientific method. For instance, the US Department of Education recently hosted a seminar entitled  Scientifically Based Research,  "where leading experts in the fields of education and science discussed the meaning of scientifically based research and its status across various disciplines." Finally, read  On Scientific Method,  a short statement by Percy W Bridgman, a famous physicist, (Reflections of a Physicist. 2d ed. New York: Philosophical Library. 1955).   Topics What is so special about science that we should worry about what it is? If you watch tv or read newspapers, you know how often we appeal to the authority of science and of scientists. You also know that governments and other institutions equally often rely on the judgment and opinion of experts in drafting many of their policies, laws and regulations. Our views, even approximate, of the universe (from the vastness of space to the atomic realm) are largely based on the discoveries of science. Much of what we believe about our bodies, about health and sickness, has a similar origin. We even worry about reconciling science and religion. There is no question, it would seem, that science is a fundamental part of our lives and of our outlook on life. Before proceeding any further, we must examine the word science itself. The etymology of this word is simple enough: it derives from the Latin scire, a verb which means 'to know.' Although, as a word, 'science' appeared in English in the fourteenth century, the cognate word 'scientist' appeared only in 1834. This is interesting. Before that date, how were the practitioners of science called? Newton, for instance, was known as a natural philosopher. Notice that 'philosopher' derives from the Greek, and means 'lover of wisdom.' These few observation should offer some evidence that the meaning of science has probably undergone many transformations, and is likely to reflect the culture in which the term was used. This means that what we pack nowadays in this word is probably determined, at least in part, by our culture, and may not be as absolute as we thought. A somewhat related question has to do with the content of the word science. Normally we use it to denote a lot of possibly different disciplines: biology, chemistry, physics, etc. If we want to understand what science means, are we authorized to lump together under this umbrella term all these disciplines? Are biology's methods of inquiry the same as those of chemistry? This is a difficult question which reaches somewhat beyond the scope of this course. It is important however to remember that it is a question to which no final answer has been given yet. Galileo's Design for a Pendulum Clock The empirical, or scientific method is a rather generic term which, with many variations, was first proposed by Francis Bacon (1561-1626) and Galileo Galilei (1564-1642). One common version is as follows: Make some observations Formulate a hypothesis that seems to be consistent with your observations Make new observations, and check whether your hypothesis is also consistent with them If necessary, modify your hypothesis to fit both old and new observations Repeat the procedure, until there are no more discrepancies between your hypothesis and all your observations If this is not possible, discard your hypothesis and try to replace it with a better one. And so on... If you ask most practicing scientists, they would generally agree that that's how they 'do science.' Is that true? We will see in the next lecture that things are not so easy, and that there are important questionable assumptions hidden under such a simple formulation. For the time being let's consider a classical example of the scientific method at work. In 1772 a German astronomer, Johann Ehlert Bode published what became known as Bode's Law. In fact, the credit should go to a German mathematician, Johann Titius, but that's another story... Titius and Bode, and many other astronomers of the time, were interested in understanding why the planets are where they are in the solar system. Why should the Earth orbit at about 150,000,000 km from the Sun? This is a difficult question, and even today we don't really have a satisfactory answer. By the late eighteenth century astronomers had already measured the distances of all the planets then known from the Sun. These were the initial observations Bode started with. When you look at the data,  keep in mind that the farthest planet known at the time was Saturn. Bode tried to find a hypothesis that would fit these data. He came up with a simple formula. He first expressed all the data in so-called astronomical units. One AU is the average distance of the Earth from the Sun. His hypothesis was as follows: Assign the number 0 to Mercury, 3 to Venus, 6 to Earth, 12 to Mars, 24 to Jupiter and 48 to Saturn Add 4 to each of these numbers Divide the results by 10 If you now compare the numbers so obtained to the actual distances of these planets from the Sun, you find a remarkable match. Of course you may well ask: why 0, 3, 6. etc.? why add 4? why divide by 10? The answer is that initially a hypothesis must only satisfy one criterion: it must fit the data. You may get the idea from a dream, from a genie, from the depths of your unconscious, from wherever. Is it consistent with the observations? If yes, you are in business. Bode was in business. Well,...almost. You see, the Asteroid Belt, an area between Mars and Jupiter where we now know thousands of smaller bodies orbit, had not been discovered yet. So, the predicted distance for Jupiter was too small, and so was that of Saturn (which in fact seemed to correspond to the actual distance of Jupiter). Since however things were fine for Mercury, Venus, Earth and Mars, Bode was reluctant to abandon his hypothesis. Please note: if Bode had been following the scientific method as outlined above, he should have discarded his hypothesis. But he did not, perhaps because he hoped there was more to the solar system than he knew. In 1781 a British astronomer, William Herschel, discovered Uranus. Bode extended his  table,  by assigning 96 to Uranus and applying the formula. Unfortunately the formula predicted the wrong distance for Uranus (but strangely, once again, the number so obtained seemed to correspond to another planet, Saturn). Then, on January 1st, 1801, an Italian astronomer, Giuseppe Piazzi, discovered a small planet, Ceres, which was precisely at the (wrong) distance predicted for Jupiter. Now the table seemed to be correct, from Mercury to Uranus. Ceres turned out to be the biggest body in what is now known as the Asteroid Belt. Here you see the predictive power that 'good' hypotheses have. Bode died long before new planets were discovered. In 1846, the German astronomer Johann Galle discovered Neptune, and in 1930 the British astronomer Clyde Tombaugh discovered Pluto. Bode would have been rather disturbed by these discoveries, as you can see in the table. Here is one important observation: Bode's formula never stops. You can apply it over and over again, obtaining distances which do not correspond to anything. Thus, even if the known planets were to fit it perfectly, Bode's law is intrinsically flawed, as it predicts infinitely more bodies than it was asked to. One example is, of course, hardly sufficient to show the limitations of the scientific method. In the next lecture we will see that there are more fundamental objections to this account of how science is done. Questions and Exercises Leaf through some newspaper or magazine, and identify appeals to the authority of science or scientists. What is your current (i.e. prior to this class) understanding of what science is all about? When do you think science started? Do you think science is a phenomenon common to all cultures? If you have access to a good library, open the unabridged Oxford Dictionary and look up the word 'science.'   Picture Credit: National Museum of Science & Industry, London. Last Modification Date: 07 July 2008