5. Science and Technology

In this section, you will find out why the fancy word "paradigm" came to be so popular, and what its technical meaning really is; you will also learn the meaning of some other amusing words, such as "hagiography." But most importantly, you should get an appreciation of the history and the actual inner workings of science and technology.

One theme for this section is that science and technology are inseparable, from which (given the previous section) it follows that science, technology and society are inseparable. For example, society determines what basic research gets done, which in turn influences what technologies can exist, which then again influences the social choices of what basic research to invest in.

But before pursuing this, we need a deeper understanding of science. This is a very nontrivial task. The history, philosophy and sociology of science are each huge areas, in fact, each is a whole department (or at least a program) in most major universities, with dozens of courses, and with degrees at all levels. We will have to get along with about one hour for each. Some of you may find parts of this rather tough going, a fast trip through some dense, deep material. Sorry! Fasten your seat belts!

5.1 The Renaissance and Classical Periods

I want to begin rather gently, with some of the stories that are often told to justify the existence of science as it is currently practiced. (Later, we will consider some aspects of such stories more critically, and later still we will consider the roles that myths and stories play in society.)

Heroic characters like Galileo, Bruno and Newton typically play important roles in these narratives. For example, it is said that Bruno and Galileo showed courage in standing up against the Catholic Church for their beliefs, that Bruno died for doing so, and that Galileo might have. Giordano Bruno, born circa 1548, was burned at the stake in Rome on 17 February 1600, for saying things like

Innumerable suns exist; innumerable earths revolve around these suns in a manner similar to the way the seven planets revolve around our sun. Living beings inhabit these worlds.

Bruno was a mystically inclined Dominican monk, not a scientist in the modern sense, despite his interest in astronomy. However, Galileo Galilei (1561-1626) was a scientist; he arrived at his theories far more rigorously than Bruno did, and he too had trouble with the Church's Inquisition, in particular, for his belief that the Earth revolved around the Sun, rather than vice versa. If he had been as stubborn as Bruno, he too would probably have been killed, instead of merely sentenced to life imprisonment (though he spent most of it in house arrest at his country villa.) Galileo is famous for his experiments with falling bodies, done from the Leaning Tower of Pisa; what is not well known is that the experiments were a failure, and as a result he was run out of town! For more information on Galileo, see for example the St Andrews webpage on Galileo.

The moral of such stories is usually taken to be something like this: we need science in order to find out objectively what is really true, independently of all religious, political, and commercial interests. Science is the search for truth, and its results are far more reliable that results found by other methods, which tend to be tainted by various special interests. Some scientists are taken to be great heroes, and their stories often read like hagiographies (this word refers to a written history of a saint).

We should go back to the ancient Greeks for the orgins of modern science, or even further, to the ancient Egyptians, who used practical geometry for very complex engineering projects like the pyramids. The contribution of the Greeks was to systematize this knowledge, by showing how it could be derived from a small number of basic principles, called axioms; this development reached its peak in the famous Elements of Euclid. (The Egyptians also had sophisticated schemes for doing arithmetic, as did the Babylonians, Assyrians, etc., who used theirs mainly for accounting.) The most distinctive feature of Greek geometry is that it is deductive; this was a major advance, and the beginning of modern mathematics. But because there was less emphasis on experiment than on rationality, modern empirical science was not yet visible.

Moving very quickly through time now, the Romans did little to advance mathematics or science; their interests were largely practical, and their contributions were more in law, warfare and engineering. After the sacking of Rome by the (so called) barbarians came the period called the "middle ages" or sometimes the "dark ages," during which only a few monks had any knowledge of what the Greeks had achieved, and no major advances occurred. During the period called the "renaissance," and mainly in Italy, things began to change. Bruno and Galileo were among those in the forefront of this; there were also of course many very great artists, like Michaelango, Gioti, and Leonardo da Vinci, who was also a great engineer and inventor.

Rene Descartes (1569-1650) is another important figure in the development of modern science; his ideas provide philosophical foundations for much of modern thought. His aim was to justify the separation of science from theology, so that science could proceed without interference from the Church. He did this by asserting that matter and spirit were two completely different realms, which he called res extensa and res cogitans (things with extension in space, and things of thought); this doctrine is called dualism. Under this view, the Church has authority over the spiritual realm, while the material realm remains open to empirical investigation. Of course Descartes could not state his goal publicly, or he would have had as much trouble as Bruno, or at least Galileo; but he did state this goal in a letter to a friend. Galileo and Descartes appear early in the period called classical or enlightment, the age of rationalism, and of mechanism. Descartes made major contributions to mathematics, especially his algebraicization of geometry, called "analytic geometry" and enshrined in the phrase "Cartesian coordinates." This is perhaps the prime example of reductionism.

Sir Isaac Newton (1642-1727) is undoubtedly the greatest scientist of the classical period. He is best known for his physics, including his laws of motion, his theory of gravitation, his proof that the orbits of the planets are elliptical, his work in optics, and more. He was the Lucasian Professor at Cambridge, and also served as Master of the Mint for England, and hence was an important public figure. It is not so well known that most of his written work consists of attacks on orthodox theological positions, especially the trinity; this was long kept secret, because his professorship was at Trinity College. It is even less well known that most of his experimental work was not in physics at all, but in alchemy! (He died of mercury poisoning, contracted from his alchemical experiments.) So Newton is not the great hero of pure rationality that he is often made out to be. (For details, see the book on Newton in the list of recommended books for this class.)

In fact, early scientists had little understanding of what science is; this only developed gradually, and is still hotly debated today, as we will see. Francis Bacon (1551-1626) and Robert Boyle (1627-91) were early promoters of the experimental method; Bacon was Lord Keeper of the Seal and later Lord Chancellor of England; he too died of effects of his experiments, bronchitis after stuffing a foul with snow (pun: he died of foul play). He is also one of the people claimed to have written the plays of Shakespeare. Boyle is famous for Boyle's law, and is one of the most important founders of modern chemistry.

5.2 Some Later Developments

Later, a split developed between rationalism and empiricism, the latter championed by two British philosophers, John Locke (1632-1704) and David Hume (1711-1776), the former by the German philosopher Immanuel Kant (1724-1804), following Descartes. Roughly speaking, rationalism is the view that we can study nature using logical inference, and empiricism is the view that we can study nature by use of our senses, i.e., that our senses give us information that corresponds to reality. Both of these presuppose realism, the view that there is an objective reality, independent of our ability to perceive it. Today, rationalism and empiricism are not longer considered to be at odds, and all three views are important epistemological assumptions underlying modern science (epistemology is the area of philosophy devoted to studying how we come to know things); that is, modern science is generally considered to use both reasoning and experiment, in order to discover what is real.

Dualism seems consistent with the traditional physical sciences (physics, chemistry, astronomy, etc.), but recent advances in sciences of the mind, especially various branches of neuroscience, call dualism into doubt. If science is devoted to material reality, then it must study the mind from a material point of view, and hence it cannot accept the assumption that the mind is non-material. Monism is the opposite of dualism; it asserts that there is just one thing in the world; that one kind of thing might be material, in which case we have materialism, or it might be spirit, which, for example, was Plato's view. Thomas Hobbes (1588-1679) was an important early proponent of materialism (he is also famous for his political philosophy). Modern neuroscience accepts the view of materialist monism. This has the effect of eliminating Descartes' mind/body dualism, but it also seems to exclude a lot of what actual living breathing human beings regard as important.

Both Descartes and Hobbes were said to have had mystical insights about the certainty of mathematics, and the profound role that this might play in science, inspired by Euclid's axiomatic geometry, and Galileo's mathematical theories of falling bodies and moving planets, which were the beginnings of modern mathematics and physics, respectively. Let me emphasize that the quantitative, mathematical deterministic character of Galileo's laws was of absolutely fundamental importance. Hobbes also tried to extend this kind of rational determinism into the social, with mixed success, but enormous influence, particularly in theories of government and law.

Another absolutely fundamental characteristic of science is its attempt to achieve objectivity, excluding all "merely" subjective factors, such as the beliefs, hopes, fears, prejudices, etc. of the experimenters, and of others (especially the Church). There is a paradoxical play upon words here, since we say that the subject of the experiment is regarded as an object, while the experimenter bans his subjectivity by becoming objective. This duality between the experimenter and the experimented upon is exactly parallel to the Cartesian duality between mind and body, so that these two seemingly opposite poles actually serve to reinforce each other, and this is what is reflected in the seemingly strange language discussed above.

As you might expect, things get much more complicated in the 20th century. We will be able to cover only a small part of this large territory, a little bit here, and then an even smaller bit later on.

5.3 Entering the Twentieth Century

Scientists of the classical era were inspired by the certainty of mathematical results, and by their amazing applicability to the physical world. The fact that Newton's physics applies to the planets, to ballistics (cannon balls, etc.), to automobile, railway engines, watches, and so much more, seems to confirm this. Even quantum mechanics supports this view, since no other physical theory has ever been accurate to so many decimal places (13 at last count). The physicist Eugene Wigner called this the unreasonable effectiveness of mathematics, wondering what it can mean about the world that mathematics can describe so many aspects of it so very well. Or does it perhaps mean something about us instead? Pythagoras (circa 572-510 BC) maintained that the world actually is mathematical, giving evidence from music and geometry, but few have been willing to go so far in more recent times. Plato held a weaker view, that mathematical truths, and all true ideas, lived in their own ideal world, of which we can see only glimpses. This is called Platonism.

One result of the success of mathematical physics was that other subjects sought to achieve the same precision and deductive rigor, by employing mathematical methods in what they hoped was a similar way. Another result was that some philosophers decided that the ideal kind of knowledge was scientific knowledge expressed with mathematical precision, and that all other kinds of knowledge were inferior; in particular, during the 1920s, the so called Vienna circle developed such views; this was a group in Vienna that included Rudolph Carnap, Moritz Schlick, Hans Reichenbach, and to some extent, the great logician Kurt Godel; they were influenced by the early work of Ludwig Wittgenstein (although he refused to become a member). Their philosophy of logical positivism held that the only meaningful sentences are those that are expressed in logic, and are either empirically verifiable, or else are logical truths (which are necessarily tautological). From this, they concluded that all metaphysics is nonsense, including religion, art, and ethics, which should therefore all be discarded. Their so called verifiability criterion came under attack from many quarters, especially in the later work of Wittgenstein, and it now has few adherents.

However, the influence of logical positivism lives on in so called analytic philosophy, which is now the dominant school in the US and Britain. And for society as a whole, the view called modernism can be seen as coherent (though not identical) with logical positivism. Although the term is used in many different ways by many different people, roughly speaking modernism calls for a homogeneity of society, an interchangeability of workers, mass consumerism in the media and in physical goods (which are called "commodities"), plus predictability, and rationality. Society is composed of autonomous rational consumers. Science is considered to support modernism. We are said to live in "modern times."

High school science textbooks (and even many college textbooks) give an outline of the scientific method that looks something like the following: (1) state a hypothesis H; (2) devise an experimental test for H; (3) carry out the experiment; (4) and then analyze the data so as to either confirm or deny H. It is often said that this leads to an ever growing body of sound empirical knowledge, and therefore to the unending progress of science, and hence of technology, and therefore society. All this is also generally considered to be part of modernity.

5.4 Paradigms and Paradigm Shifts

Thomas Kuhn introduced a very different way to conceptualize scientific progress in his famous book The Structure of Scientific Revolutions, using the notions of paradigm, crisis, revolution, and paradigm shift. See the readings for 18 October for details. But please note that Kuhn's own version differs from that of some of his interpreters, and the fact that Kuhn introduced these ideas does not necessarily mean that his versions are better; on the contrary, just as Newton's physics is better than Galileo's, it seems more likely that (at least some of) the later interpretations of Kuhn may be better than the original. Once again, I really want to encourage you to think it through for yourself.

As an example, we can consider the Ptolmaic paradigm vs. the Copernican paradigm for the heavens, noting that the Ptolmaic paradigm is deeply entwined with the Aristotelian world view, which in turn has become deeply entwined with Catholic theology. As Kuhn notes, the Copernican paradigm was not initially better than the Ptolmaic; in fact, Plolemy's approach at first gave more accurate results, until it was realized that the orbits of the planets were actually ellipses rather than circles, as Copernicus had thought.

Contrary to the high school model (and most philosophy of science until recently), experiments are not purely objective determinations of fact, but rather are theory laden, in the sense that they only make sense in the context of some particular theory; no one would think of trying to measure how long it takes objects to fall without first having some theoretical context, including (for example) notions of length and time; more generally, experiments only make sense within particular paradigms. Galileo's experiment made sense in terms of his opposition to the Aristotelian paradigm, and his own fledgling more quantitative theories. It should also be noted that theories are underdetermined with respect to data: this means that any given set of experiments can always be explained in more than one way.

Experiments are also value laden, because they are always embedded in a paradigm, and paradigms are value laden, in the sense that they involve a community with shared values, which determine what is and is not worth pursuing, what are good and bad results, what counts as data, what counts as theory, and even what counts as a problem; perhaps these values constitute the real essence of the notion of paradigm.

An important point about successive paradigms follows from this, that they are incomparable, in the sense that using the values of one paradigm to criticize another will at best give misleading results, and in general will be just plain wrong. For example, Aristotle's physics was not really about "motion" in the same sense as Galileo's. Nevertheless, it is quite usual for each paradigm to give a rational reconstruction of the preceeding paradigm, reevaluating the older material in terms of its own values. This makes for shorter, more coherent textbooks, but it also makes for bad history. In particular, Galileo's experiments did not prove that Aristotle's theory of motion was wrong, because Aristotle's notion of motion was more phenomenological, i.e., it was more concerned with our natural perception of motion, what we intuitively feel about motion, than with the results of objective (and artificial) experimental measurements.

As a result of the incomparability of paradigms, it is not correct to say that a later paradigm is better than an earlier paradigm in absolute terms, although of course it will be better in its own terms, and it may well be better for certain particular purposes. Another interesting observation is that a paradigm is likely to be more coherent with the values of the culture that produced it than with some earlier (or later) culture. It is this, plus the rational reconstruction of earlier paradigms, and the fact that progress does occur within a paradigm during normal science (that is, until a crisis appears) that supports the myth of steady progress. Thus, standing within our own culture and some current paradigm, we may genuinely be entitled to say that things have progressed. But we should also realize that this is relative to a set of values that is not absolute. For example, the Nazis no doubt saw things getting better and better during the 1930s, relative to their own values.

The Nazi example suggests why we should not give in to the total moral relativism that is found in some quarters. For example, I am quite willing to say that taking life is bad, while still recognizing that this is not a value that everyone shares at every point in time, or interprets in the same way that I would. The fact that people may hold different values does not imply that there are no values, nor does it imply that value systems cannot be compared, with some being found better than others.

Paradigms are naturally conservative, in there is a great reluctance to overturn their fundamental values, paradigmatic experiments, etc.; this makes sense because these define the paradigm. Rather, things that don't fit are seen as puzzles to be worked on and solved, and if after long effort they still don't fit, then they are ostracized as anomalies. If some field is too willing to change its own fundamentals, then it will not be seen as scientific, but rather as disorganized and chaotic, and therefore as pre-paradigmatic, i.e., not yet realizing normal science in a fixed paradigm.

Contemporary theoretical physics is in a state of crisis (in Kuhn's technical sense of that term), because its two major field-based theories seem to make incompatible assumptions about nature, and no one as yet knows how to reconcile them. These theories are quantum mechanics and relativity, and their as yet speculative combination is called quantum gravity, and also general unified field theory (sometimes "GUT" for short).

5.5 Statistics

Statistics plays a fundamental role in most science today, because it is well known that measurements are always somewhat inaccurate, and that repeated measurements are necessary to ensure accuracy. Furthermore, it's not enough to just compute an average and proclaim "Well that looks close enough to me". Indeed, statistics has become a very sophisticated subject, and we will just skim a few main points here. First, a statistic is a function for computing a value that summarizes some dataset. Each statistic, in this sense, has its own probability distribution, and therefore has a certain likelihood of giving incorrect values in a given experiment. So experimenters should ensure that the probability of drawing a false conclusion from a given statistic is sufficiently small for the purpose at hand.

The standard approach is called hypothesis testing: there is a so called null hypothesis, which says that what you are testing is false, and you hope for a high probability that the null hypothesis is false, and that the hypothesis you are testing is therefore true with a high probability. This corresponds to the dictum that you can never prove hypotheses in science, but only disprove them. Karl Popper is famous for his doctrine that only falsifiable assertions can be scientific (in part, this was an attempt to improve on the logical positivists). But science as it is practiced often takes a looser approach than discussions of this kind suggest; e.g., very few doubt that cosmology is a science, even though experiments are impossible, since we only have one universe.

Especially in the social sciences and medicine, statistical tests are often used to determine the degree to which variables are correlated or covariant, that is, the degree to which they vary together. In many cases the goal is determine whether or not one variable "causes" another. For example, cigarettes and cancer have been clearly shown to covary, but this does not in itself prove that cigarettes cause cancer; it might be that some other factor predisposes people to both cancer and cigarettes; it might even have been the case that cancer predisposes people to smoking! In the 1950s, when attacks on the cigarette manufacturers began, exactly this kind of argument was made in the courts, and at that time, it won! Now we know more about the underlying mechanisms, so the situation is very different, and the argument that statistical tests do not prove causation cannot prevail. (There are also many examples where absolutely false causal inferences have been drawn from statistics, so the cigarette example should not be taken as paradigmatic! See the reading on statistics in medicine.)

In passing, I would like to mention that, shockingly to many people, probabilities enter into the very foundations of quantum mechanics; QM does not directly predict outcomes, but only the probability distributions of outcomes; and furthermore, the Hiesenberg uncertainty principle says that attempting to measure one variable (say position) more accurately will cause another variable (such as momentum) to become more uncertain than it was before. So absolute certainty is no longer something that modern science can promise.

5.6 Summary and Discussion

One clear trend during the period discussed in this section is a gradual diminution of the influence of the Church, and of the spiritual in favor of the material. This can be seen in the progression of positions held by Bruno, Galileo, Descartes, Kant, and Wittgenstein (and generally speaking, with some exceptions of course, those in between).

Although the material in the section should give us some idea of the history and philosophy of science, it does not give much of an idea about how science and technology are related. One obvious point is that technology provides infrastructure for science. The huge experiments of modern physics are also huge engineering projects, e.g., consider the Stanford Linear Accelerator (SLAC), with its one mile of magnets accelerating particles in an incredably straight line; whole teams worked on designing, testing and building just these very special magnets; another whole team used lasers to ensure the linear alignment of the beam.

And of course, it is also said that science underlies technology. For example, Newton's optics was used in working with the laser beams that aligned the magnets at SLAC. Finally, it is said that technology converts the abstract truths of science into tangible benefits for society. For example, what is learned about particle physics at SLAC may help us build better bombs to defend democracy, and eventually even better consumer products. But is the picture really so simple as this? A recent area called "Social Studies of Science" does not think so, as we will see in the next section.