Summer Assignment Two

Bios,
Hey all of you! Post your comments to the first summer assignment. That is how you turn in your work and get credit. As I write this, only three have responded to the first assignment.

This week we wrap-up our look at the nature of science with another classic in the philosophy of science cannon, “Science: Conjectures and Refutations” by Karl Popper. This essay is meaty so take your time to digest what it has to offer.

But first, some vocabulary -

1. Induction: inferring a general conclusion or principle from particular instances (from specific to general). The theory of plate tectonics (general principle) is inferred from many individual evidences (specifics).
2. Deduction: inference in which the conclusion about particulars follows from general principle (from general to specific). Sherlock Holms used deduction. Fingerprints are unique to the individual (general principle) so if the suspect’s fingerprints are on the knife, he held the knife (specific).
3. Demarcation: to set apart, distinguish

Distinguishing science from pseudo-science:
Finding truth through science is an empirical process based on inductive reasoning. It is different from other “truth” finding activities such as astrology and tarot card reading, which are based on other principles. While induction does result in new knowledge it comes at a cost. The cost is that science is tentative and subject to revision. Due to the nature of science, two philosophical problems arise. The first problem is distinguishing science from pseudo-science also known as the problem of demarcation. For example, what makes astronomy science yet astrology not? The second problem is the logical problem of induction. In other words how can science find truth if it is always tentative and subject to revision? You will find that being tentative - subject to revision is the strength of science!

The philosopher, Sir Karl Popper (1902-1994) addressed these problems in the essay you are about to read. In the essay he first distinguishes science from pseudo-science by solving the problem of demarcation. He then explores the logical problem of induction and concludes that it and the problem of demarcation are the same. The ideas presented in this essay likely are new to you. Your understanding will require careful attention to the essay, thoughtful responses to the questions, and careful discussion with your instructor. There are two primary objectives for this activity. First, you will learn what separates science from pseudo-science. Second, will be to understand how we can know a theory is true even if it is tentative and subject to revision.

My hope is that after reading these two essays you begin to appreciate the dimensions of science. As you have already discovered, science is not just doing experiments. It is much more – a grand achievement of the human mind that is capable of understanding the universe in which we live.

So sit back, relax, and enjoy Popper’s essay you will find the questions at the end of the essay.

See you in class. I am looking forward to meeting you.

Mr. Baker

Karl Popper - Science: Conjectures and Refutations

Mr. Turnbull had predicted evil consequences, . . . and was now doing the best in his power to bring about the verification of his own prophecies. Anthony Trollope

When I received the list of participants in this course and realized that I had been asked to speak to philosophical colleagues I thought, after some hesitation and consultation that you would probably prefer me to speak about those problems which interest me most, and about those developments with which I am most intimately acquainted. I therefore decided to do what I have never done before: to give you a report on my own work in the philosophy of science, since the autumn of 1919 when I first began to grapple with the problem, "When should a theory be ranked as scientific?" or "Is there a criterion for the scientific character or status of a theory?"

The problem which troubled me at the time was neither, "When is a theory true?"nor, "When is a theory acceptable?" My problem was different. I wished to distinguish between science and pseudo-science; knowing very well that science often errs, and that pseudo-science may happen to stumble on the truth.

I knew, of course, the most widely accepted answer to my problem: that science is distinguished from pseudo-science or from "metaphysics" by its empirical method, which is essentially inductive, proceeding from observation or experiment. But this did not satisfy me. On the contrary, I often formulated my problem as one of distinguishing between a genuinely empirical method and a non-empirical or even a pseudo-empirica1 method-that is to say, a method which, although it appeals to observation and experiment, nevertheless does not come up to scientific standards. The latter method may be exemplified by astrology with its stupendous mass of empirical evidence based on observation-on horoscopes and on biographies.

But as it was not the example of astrology which led me to my problem I should perhaps briefly describe the atmosphere in which my problem arose and the examples by which it was stimulated. After the collapse of the Austrian Empire there had been a revolution in Austria: the air was full of revolutionary slogans and ideas, and new and often wild theories. Among the theories which interested me Einstein's theory of relativity was no doubt by far the most important. Three others were Marx's theory of history, Freud's psycho-analysis, and Alfred Adler's so-called "individual psychology."

There was a lot of popular nonsense talked about these theories, and especially about relativity (as still happens even today), but I was fortunate in those who introduced me to the study of this theory. We all-the small circle of students to which I belonged-were thrilled with the result of Eddington's eclipse observations which in 1919 brought the first important confirmation of Einstein's theory of gravitation. It was a great experience for us, and one which had a lasting influence on my intellectual development.

The three other theories I have mentioned were also widely discussed among students at that time. I myself happened to come into personal contact with Alfred Adler, and even to co-operate with him in his social work among the children and young people in the working-class districts of Vienna where he had established social guidance clinics.

It was during the summer of 1919 that I began to feel more and more dissatisfied with these three theories-the Marxist theory of history, psychoanalysis, and individual psychology; and I began to feel dubious about their claims to scientific status. My problem perhaps first took the simple form, "What is wrong with Marxism, psycho-analysis, and individual psychology? Why are they so different from physical theories, from Newton's theory, and especially from the theory of relativity?"

To make this contrast clear I should explain that few of us at the time would have said that we believed in the truth of Einstein's theory of gravitation. This shows that it was not my doubting the truth of those other three theories which bothered me, but something else. Yet neither was it that I merely felt mathematical physics to be more exact than the sociological or psychological type of theory. Thus what worried me was neither the problem of truth, at that stage at least, nor the problem of exactness or measurability. It was rather that I felt that these other three theories, though posing as sciences, had in fact more in common with primitive myths than with science; that they resembled astrology rather than astronomy.

I found that those of my friends who were admirers of Marx, Freud, and Adler, were impressed by a number of points common to these theories, and especially by their apparent explanatory power. These theories appeared to be able to explain practically everything that happened within the fields to which they referred. The study of any of them seemed to have the effect of an intellectual conversion or revelation, opening your eyes to a new truth hidden from those not yet initiated. Once your eyes were thus opened you saw confirming instances everywhere: the world was full of verifications of the theory. Whatever happened always confirmed it. Thus its truth appeared manifest; and unbelievers were clearly people who did not want to see the manifest truth; who refused to see it, either because it was against their class interest, or because of their repressions which were still "un-analysed" and crying aloud for treatment.

The most characteristic element in this situation seemed to me the incessant stream of confirmations, of observations which "verified" the theories in question; and this point was constantly emphasized by their adherents. A Marxist could not open a newspaper without finding on every page confirming evidence for his interpretation of history; not only in the news, but also in its presentation-which revealed the class bias of the paper-and especially of course in what the paper did not say. The Freudian analysts emphasized that their theories were constantly verified by their "clinical observations." As for Adler, I was much impressed by a personal experience. Once, in 1919, 1 reported to him a case which to me did not seem particularly Adlerian, but which he found no difficulty in analysing in terms of his theory of inferiority feelings, although he had not even seen the child. Slightly shocked, I asked him how he could be so sure. "Because of my thousandfold experience," he replied; whereupon I could not help saying: "And with this new case, I suppose, your experience has become thousand-and-one-fold."

What I had in mind was that his previous observations may not have been much sounder than this new one; that each in its turn had been interpreted in the light of "previous experience," and at the same time counted as additional confirmation. What, I asked myself, did it confirm? No more than that a case could be interpreted in the light of the theory. But this meant very little, I reflected, since every conceivable case could be interpreted in the light of Adler's theory, or equally of Freud's. I may illustrate this by two very different examples of human behaviour: that of a man who pushes a child into the water with the intention of drowning it; and that of a man who sacrifices his life in an attempt to save the child. Each of these two cases can be explained with equal ease in Freudian and in Adlerian terms. According to Freud the first man suffered from repression (say, of some component of his Oedipus complex), while the second man had achieved sublimation. According to Adler the first man suffered from feelings of inferiority (producing perhaps the need to prove to himself that he dared to commit some crime), and so did the second man (whose need was to prove to himself that he dared to rescue the child). I could not think of any human behaviour which could not be interpreted in terms of either theory. It was precisely this fact-that they always fitted, that they were always confirmed-which in the eyes of their admirers constituted the strongest argument in favour of these theories. It began to dawn on me that this apparent strength was in fact their weakness.

With Einstein's theory the situation was strikingly different. Take one typical instance-Einstein's prediction, just then confirmed by the findings of Eddington's expedition. Einstein's gravitational theory had led to the result that light must be attracted by heavy bodies (such as the sun), precisely as material bodies were attracted. As a consequence it could be calculated that light from a distant fixed star whose apparent position was close to the sun would reach the earth from such a direction that the star would seem to be slightly shifted away from the sun; or, in other words, that stars close to the sun would look as if they had moved a little away from the sun, and from one another. This is a thing which cannot normally be observed since such stars are rendered invisible in daytime by the sun's overwhelming brightness; but during an eclipse it is possible to take photographs of them. If the same constellation is photographed at night one can measure the distances on the two photographs, and check the predicted effect.

Now the impressive thing about this case is the risk involved in a prediction of this kind. If observation shows that the predicted effect is definitely absent, then the theory is simply refuted. The theory is incompatible with certain possible results of observation-in fact with results which everybody before Einstein would have expected. This is quite different from the situation I have previously described, when it turned out that the theories in question were compatible with the most divergent human behaviour, so that it was practically impossible to describe any human behaviour that might not be claimed to be a verification of these theories.

These considerations led me in the winter of 1919-20 to conclusions which I may now reformulate as follows.

(1) It is easy to obtain confirmations, or verifications, for nearly every theory-if we look for confirmations.

(2) Confirmations should count only if they are the result of risky predictions; that is to say, if, unenlightened by the theory in question, we should have expected an event which was incompatible with the theory-an event which would have refuted the theory.

(3) Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is.

(4) A theory which is not refutable by any conceivable event is nonscientific. Irrefutability is not a virtue of theory (as people often think) but a vice.

(5) Every genuine test of a theory is an attempt to falsify it, or to refute it. Testability is falsifiability; but there are degrees of testability; some theories are more testable, more exposed to refutation, than others; they take, as it were, greater risks.

(6) Confirming evidence should not count except when it is the result of a genuine test of the theory; and this means that it can be presented as a serious but unsuccessful attempt to falsify the theory. (I now speak in such cases of "corroborating evidence.")

(7) Some genuinely testable theories, when found to be false, are still upheld by their admirers-for example by introducing ad hoc some auxiliary assumption, or by re-interpreting theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at the price of destroying, or at least lowering, its scientific status. (I later described such a rescuing operation as a "conventionalist twist" or a "conventionalist stratagem.")

One can sum up all this by saying that the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.

II

I may perhaps exemplify this with the help of the various theories so far mentioned. Einstein's theory of gravitation clearly satisfied the criterion of falsifiability. Even if our measuring instruments at the time did not allow us to pronounce on the results of the tests with complete assurance, there was clearly a possibility of refuting the theory.

Astrology did not pass the test. Astrologers were greatly impressed, and misled, by what they believed to be confirming evidence_so much so that they were quite unimpressed by any unfavourable evidence. Moreover, by making their interpretations and prophecies sufficiently vague they were able to explain away anything that might have been a refutation of the theory had the theory and the prophecies been more precise. In order to escape falsification they destroyed the testability of their theory. It is a typical soothsayer's trick to predict things so vaguely that the predictions can hardly fail: that they become irrefutable.

The Marxist theory of history, in spite of the serious efforts of some of its founders and followers, ultimately adopted this soothsaying practice. In some of its earlier formulations (for example in Marx's analysis of the character of the "coming social evolution') their predictions were testable, and in fact falsified.2 Yet instead of accepting the refutations the followers of Marx reinterpreted both the theory and the evidence in order to make them agree. In this way they rescued the theory from refutation; but they did so at the price of adopting a device which made it irrefutable. They thus gave a "conventionalist twist" to the theory; and by this stratagem they destroyed its much advertised claim to scientific status.

The two psycho-analytic theories were in a different class. They were simply non-testable, irrefutable. There was no conceivable human behaviour which could contradict them. This does not mean that Freud and Adler were not seeing certain things correctly: I personally do not doubt that much of what they say is of considerable importance, and may well play its part one day in a psychological science which is testable. But it does mean that those "clinical observations" which analysts naively believe confirm their theory cannot do this any more than the daily confirmations which astrologers find in their practice.3 And as for Freud's epic of the Ego, the Super-ego, and the Id, no substantially stronger claim to scientific status can be made for it than for Homer's collected stories from Olympus. These theories describe some facts, but in the manner of myths. They contain most interesting psychological suggestions, but not in a testable form.

At the same time I realized that such myths may be developed, and become testable; that historically speaking all-or very nearly all-scientific theories originate from myths, and that a myth may contain important anticipations of scientific theories. Examples are Empedocles' theory of evolution by trial and error, or Parmenides' myth of the unchanging block universe in which nothing ever happens and which, if we add another dimension, becomes Einstein's block universe (in which, too, nothing ever happens, since everything is, four dimensionally speaking, determined and laid down from the beginning). I thus felt that if a theory is found to be non-scientific, or "metaphysical" (as we might say), it is not thereby found to be unimportant, or insignificant, or "meaningless," or "nonsensical." it cannot claim to be backed by empirical evidence in the scientific sense-although it may easily be, in some genetic sense, the "result of observation."

(There were a great many other theories of this pre-scientific or pseudoscientific character, some of them, unfortunately, as influential as the Marxist interpretation of history; for example, the racialist interpretation of history-another of those impressive and all-explanatory theories which act upon weak minds like revelations.)

Thus the problem which I tried to solve by proposing the criterion of falsifiability was neither a problem of meaningfulness or significance, nor a problem of truth or acceptability. It was the problem of drawing a line (as well as this can be done) between the statements, or systems of statements, of the empirical sciences, and all other statements-whether they are of a religious or of a metaphysical character, or simply pseudo-scientific. Years later-it must have been in 1928 or 1929-I called this first problem of mine the "problem of demarcation. " The criterion of falsifiability is a solution to this problem of demarcation, for it says that statements or systems of statements, in order to be ranked as scientific, must be capable of conflicting with possible, or conceivable, observations....

III

Let us now turn from our logical criticism of the psychology of experience to our real problem-the problem of the logic of science. Although some of the things I have said may help us here, in so far as they may have eliminated certain psychological prejudices in favour of induction, my treatment of the logical problem of induction is completely independent of this criticism, and of all psychological considerations. Provided you do not dogmatically believe in the alleged psychological fact that we make inductions, you may now forget my whole story with the exception of two logical points: my logical remarks on testability or falsifiability as the criterion of demarcation; and Hume's logical criticism of induction.

From what I have said it is obvious that there was a close link between the two problems which interested me at that time: demarcation, and induction or scientific method. It was easy to see that the method of science is criticism, i.e. attempted falsifications. Yet it took me a few years to notice that the two problems-of demarcation and of induction-were in a sense one....

I recently came across an interesting formulation of this belief in a remarkable philosophical book by a great physicist-Max Born's Natural Philosophy of Cause and Chance.5 He writes: "Induction allows us to generalize a number of observations into a general rule: that night follows day and day follows night . . . But while everyday life has no definite criterion for the validity of an induction, . . .science has worked out a code, or rule of craft, for its application." Born nowhere reveals the contents of this inductive code (which, as his wording shows, contains a "definite criterion for the validity of an induction"); but he stresses that "there is no logical argument" for its acceptance: "it is a question of faith"; and he is therefore "willing to call induction a metaphysical principle." But why does he believe that such a code of valid inductive rules must exist? This becomes clear when he speaks of the "vast communities of people ignorant of, or rejecting, the rule of science, among them the members of anti-vaccination societies and believers in astrology. It is useless to argue with them; I cannot compel them to accept the same criteria of valid induction in which I believe: the code of scientific rules." This makes it quite clear that "valid induction" was here meant to serve as a criterion of demarcation between science and pseudo-science.

But it is obvious that this rule or craft of "valid induction" is not even metaphysical: it simply does not exist. No rule can ever guarantee that a generalization inferred from true observations, however often repeated, is true.(Born himself does not believe in the truth of Newtonian physics, in spite of its success, although he believes that it is based on induction.) And the success of science is not based upon rules of induction, but depends upon luck, ingenuity, and the purely deductive rules of critical argument.

I may summarize some of my conclusions as follows:

(1) Induction, i.e. inference based on many observations, is a myth. It is neither a psychological fact, nor a fact of ordinary life, nor one of scientific procedure.

(2) The actual procedure of science is to operate with conjectures: to jump to conclusions-often after one single observation (as noticed for example by Hume and Born).

(3) Repeated observations and experiments function in science as tests of our
conjectures or hypotheses, i.e. as attempted refutations.

(4) The mistaken belief in induction is fortified by the need for a criterion of demarcation which, it is traditionally but wrongly believed, only the inductive method can provide.

(5) The conception of such an inductive method, like the criterion of verifiability, implies a faulty demarcation.

(6) None of this is altered in the least if we say that induction makes theories only probable rather than certain.

IV

If, as I have suggested, the problem of induction is only an instance or facet of the problem of demarcation, then the solution to the problem of demarcation must provide us with a solution to the problem of induction. This is indeed the case, I believe, although it is perhaps not immediately obvious.

For a brief formulation of the problem of induction we can turn again to Born, who writes: ". . . no observation or experiment, however extended can give more than a finite number of repetitions"; therefore, "the statement of a law-B depends on A-always transcends experience. Yet this kind of statement is made everywhere and all the time, and sometimes from scanty material.'

In other words, the logical problem of induction arises from (a) Hume's discovery (so well expressed by Born) that it is impossible to justify a law by observation or experiment, since it "transcends experience"; (b) the fact that science proposes and uses laws "everywhere and all the time." (Like Hume, Born is struck by the "scanty material," i.e. the few observed instances upon which the law may be based.) To this we have to add (c) the principle of empiricism which asserts that in science, only observation and experiment may decide upon the acceptance or rejection of scientific statements, including laws and theories.

These three principles, (a), (b), and (c), appear at first sight to clash; and this apparent clash constitutes the logical problem of induction.

Faced with this clash, Born gives up (c), the principle of empiricism (as Kant and may others, including Bertrand Russell, have done before him), in favour of what he calls a "metaphysical principle"; a metaphysical principle which he does not even attempt to formulate; which he vaguely describes as a "code or rule of craft"; and of which I have never seen any formulation which even looked promising and was not clearly untenable.

But in fact the principles (a) to (c) do not clash. We can see this the moment we realize that the acceptance by science of a law or of a theory is tentative only; which is to say that all laws and theories are conjectures, or tentative hypotheses(a position which I have sometimes called "hypotheticism") and that we may reject a law or theory on the basis of new evidence, without necessarily discarding the old evidence which originally led us to accept it.7

The principles of empiricism (c) can be fully preserved, since the fate of a theory, its acceptance or rejection, is decided by observation and experiment_ by the result of tests. So long as a theory stands up to the severest tests we can design, it is accepted; if it does not, it is rejected. But it is never inferred, in any sense, from the empirical evidence. There is neither a psychological nor a logical induction. Only the falsity of the theory can be inferred from empirical evidence, and this inference is a purely deductive one.

Hume showed that it is not possible to infer a theory from observation statements; but this does not affect the possibility of refuting a theory by observation statements. The full appreciation of the possibility makes the relation between theories and observations perfectly clear. This solves the problem of the alleged clash between the principles (a), (b), and(c), and with it Hume's problem of induction....

NOTES
1. This is a slight oversimplification, for about half of the Einstein effect may be derived from the classical theory, provided we assume a ballistic theory of light.
2. See for example, my Open Society and Its Enemies, ch. 15, section iii, and notes 13-14.
3. "Clinical observations," like all other observations, are interpretations in the light of theories; and for this reason alone they are apt to seem to support those theories in the light of which they were interpreted. But real support can be obtained only from observations undertaken as tests (by "attempted refutations"); and for this purpose criteria of refutation have to be laid down beforehand; it must be agreed which observable situations, if actually observed, mean that the theory is refuted. But what kind of clinical responses would refute to the satisfaction of the analyst not merely a particular analytic diagnosis but psycho-analysis itself? And have such criteria ever been discussed or agreed upon by analysts? Is there not, on the contrary, a whole family of analytic concepts, such as "ambivalence" (l do not suggest that there is no such thing as ambivalence), which would make it difficult, if not impossible, to agree upon such criteria? Moreover, how much headway has been made in investigating the question of the extent to which the (conscious or unconscious) expectations and theories held by the analyst influence the "clinical responses" of the patient? To say nothing about the conscious attempts to influence the patient by proposing interpretations to him, etc.) Years ago Iintroduced the term "Oedipus effect" to describe the influence of a theory or expectation or prediction upon the event which it predicts or describes: it will be remembered that the causal chain leading to Oedpus' parricide was started by the oracle's prediction of this event. This is a characteristic and recurrent theme of such myths, but one which seems to have failed to attract the interest of the analysts, perhaps not accidentally. (The problem of confirmatory dreams suggested by the analyst is discussed by Freud, for example in Gesammelte Schriften,i 111, 1925, where he says on p. 314: "If anybody asserts that most of the dreams which can be utilized in an analysis . . . owe their origin to [the analyst's] suggestion, then no objection can be made from the point of view of analytic theory. Yet there is nothing in this fact,"he surprisingly adds, "which would detract from the reliability of our results.']
4. The case of astrology, nowadays a typical pseudo-science, may illustrate this point. It was attacked, by Aristotelians and other rationalists, down to Newton's day, for the wrong reason-for its now an accepted assertion that the planets had an "influence" upon terrestrial ("sublunar") events. In fact Newton's theory of gravity, and especially the lunar theory of the tides, was historically speaking an offpsring of astrological lore. Newton, it seems, was most reluctant to adopt a theory which came from the same stable as for example the theory that "influenza"epidemics are due to an astral "influence." And Galileo, no doubt for the same reason, actually rejected the lunar theory of the tides; and his misgivings about Kepler may easily be explained by his misgivings about astrology.
5. Max Born, Natural Philosophy of Cause and Chance, Oxford, 1949, p. 7.
6. Natural Philosophy of Cause and Chance, p. 6.
7. I do not doubt that Born and many others would agree that theories are accepted only tentatively. But the widespread belief in induction shows that the far-reaching implications of this view are rarely seen.
Source: Karl Popper, Conjectures and Refutations: The Growth of Scientific Knowledge (New York: Harper Torchbooks, 1963), pp. 33-39, 52-55.

Your Assignment:

1. What makes a theory scientific?
2. Explain why in Popper’s view Marx’s theory of history, Freud’s psycho-analysis and Alfred Adler’s “individual psychology” are not science. Please provide at least one example from the reading in your explanation.
3. Explain why Einstein’s theory of relativity is science.
4. What is the danger of ad hoc theories?
5. In your words, explain how the problem of demarcation solved?
6. What is the logical problem of induction?
7. How does Popper solve the problem of induction?
8. Why is being tentative and subject to revision the strength of science?

First 2012-13 Assignment

Bios,

Welcome to the first blog assignment of the 2012-13 school year. We will begin our study of biology by examining the nature of science. Science is a rich field of philosophical study and you will be introduced to two influential essays written on the subject.

Experiments are part of science but science is not simply experiments, otherwise science would be like a cook book. Discovered knowledge is part of science but science is not simply facts, otherwise stamp collecting would also be science. Science includes experiments and collected knowledge but it is much more. For example, how do we know? Reading these essays will help you begin to understand science and I hope cause a conversation to discuss it further.

Your assignment:
Read Dr. Ziman's essay then respond to the question below by commenting to the post.

Dr. Ziman's goal was to define science. He presented four familiar definitions for science and concludes by presenting his definition. Explain why Ziman finds the four familiar definitions lacking and how his definition addresses what he sees as the true nature of science.

Feel free to ask questions before you answer the question. To do this, simply comment to this entry. When you wish to answer the question, again simply add a comment to this entry but be sure to state that this is your answer. Your response will be your first grade.

Have fun with this and let AP Biology begin!

Mr. Baker

PUBLIC KNOWLEDGE An essay concerning the social dimension of science

J. M. ZIMAN, F.R.S. Professor of Theoretical Physics, University of Bristol
Cambridge Univ. Press, 1968.

In this essay a practicing scientist and gifted expositor sets forth a new point of view on the nature of science and how it works. Professor Ziman argues that the true goal of all scientific research is to contribute to the consensus of universally accepted knowledge. He explores the philosophical, psychological and sociological consequences of this principle, and explains how, in practice, the consensus is established and how the work of the individual scientist becomes a part of it. The intellectual form of scientific, knowledge is determined by the absolute need for the scientist to communicate his findings and to make them acceptable to other people. The internal social relations of the scientific community are. therefore all-important; the author has much to say, from his own experience, of the-'way scientists teach, communicate with, promote, criticize, honor, give ear to, and give patronage to, one another.

Professor Ziman's essay, being written in plain English, and requiring only the slenderest technical knowledge of science, can (and should) be read by any educated person; as he says "all genuine scientific procedures of thought and argument are essentially the same as those of everyday life".

WHAT IS SCIENCE?

Let every man be fully persuaded in his own mind: ROM xiv- 5

To answer the question "What is Science?" is almost as presumptuous as to try to state the meaning of Life itself. Science has become a major part of the stock of our minds; its products are the furniture of our surroundings. We must accept it, as the good lady of the fable is said to have agreed to accept the Universe.

Yet the question is puzzling rather than mysterious. Science is very clearly a conscious artifact of mankind, with well-documented historical origins, with a definable scope and content, and with recognizable professional practitioners and exponents. The task of defining Poetry, say, whose subject matter is by common consent ineffable, must be self-defeating. Poetry has no rules, no method, no graduate schools, no logic: the bards are self-anointed and their spirit bloweth where it listeth. Science, by contrast, is rigorous, methodical, academic, logical and practical. The very facility that it gives us, of clear understanding, of seeing things sharply in focus, makes us feel that the instrument itself is very real and hard and definite. Surely we can state, in a few words, it’s essential nature.

It is not difficult to state the order of being to which Science belongs. It is' one of the categories of the intellectual commentary that Man makes on his World. Amongst its kith and kin we would put Religion, Art, Poetry, Law, Philosophy, Technology, etc - the familiar divisions or 'Faculties' of the Academy or the Multiversity.

At this stage I do not mean to analyze the precise relationship that exists between Science and each of these cognate modes of thought; I am merely asserting that they are on all fours with one another. It makes some sort of sense (though it may not always be stating a truth) to substitute these words for one another, in phrases like "Science teaches us. . . “or "The Spirit of Law is. . ." or "Technology benefits mankind by..."or "He is a student of Philosophy". The famous "conflict between Science and Religion" was truly a battle between combatants of the same species between David and Goliath if you will - and not, say, between the Philistine army and a Dryad, or between a point of order and a postage stamp.

Science is obviously like Religion, Law, Philosophy, etc. in being a more or less coherent set of ideas. In its own technical language, Science is information; it does not act directly on the body; it speaks to the mind. Religion and Poetry, we may concede, speak also to the emotions, and the statements of Art can seldom be written or expressed verbally-but, they all belong in the non- material realm.

But in what ways are these, forms of knowledge unlike one another? What are the special attributes of Science? What is the criterion for drawing lines of demarcation about it, to distinguish it from Philosophy, or from Technology, or from Poetry?

This question has long been debated. Famous books have been devoted to it. It has been the theme of whole schools of philosophy. To give an account of all the answers, with all their variations, would require a history of Western thought. It is a daunting subject. Nevertheless, the types of definition with which we are familiar can be stated crudely.

Science is the Mastery of Man's Environment. This is, I think, the vulgar conception. It identifies Science with its products; it points to penicillin or to an artificial satellite and tells us of all the wonderful further powers that man will soon acquire by the, same agency.

This definition enshrines two separate errors. In the first place it confounds Science, with Technology. It puts all its emphasis on the applications of scientific knowledge and gives no hint as to the intellectual procedures by which that knowledge may be successfully obtained. It does not really discriminate between Science and Magic, and gives us no reason for studies such as Cosmology and Pure Mathematics, which seem entirely remote from practical use.

It also confuses ideas with things. Penicillin is not Science, any more than a cathedral is Religion or a witness box is Law. The material manifestations and powers of Science, however beneficial, awe-inspiring, monstrous, or beautiful, are not even symbolic; they belong in a different logical realm, just as a building is not equivalent to or symbolic of the architect's blueprints. A meal is not the same thing as a recipe.

Science is the Study of the Material World. This sort of definition is also very familiar in popular thought. It derives, I guess, from the great debate between Science and Religion, whose outcome was a treaty of partition in which Religion was left with the realm of the Spirit whilst Science was allowed full sway in the territory of Matter.

Now it is true that one of the aims of Science is to provide us with a Philosophy of Nature, and it is also true that many questions of a moral or spiritual kind cannot be answered at all within a scientific framework. But the dichotomy between Matter and Spirit is an obsolete philosophical notion which does not stand up very well to careful critical analysis. If we stick to this definition we may end up in a circular argument in which Matter is only recognizable as the subject matter of Science. Even then, we shall have stretched the meaning of words a long way in order to accommodate Psychology, or Sociology, within the scientific stable.

This definition would also exclude Pure Mathematics. Surely this is wrong. Mathematical thinking is so deeply entangled with the physical sciences that one cannot draw a line between them. Modern mathematicians think of themselves as exploring the logical consequences (the 'theorems') of different sets of hypotheses or 'axioms', and do not claim absolute truth, in a material sense, for their results. Theoretical physicists and applied mathematicians try to confine their explorations to systems of hypotheses that they believe to reflect properties of the 'real' world, but they often have no license for this belief it would be absurd to have to say that Newton's Principia, and all the work that was built upon it, was not now Science, just because we now suppose that the inverse square law of gravitation is not perfectly true in an Einsteinian universe. I suspect that the exclusion of the 'Queen of the Sciences' from her throne is a relic of some ancient academic arrangement, such as the combination of classical literary studies with mathematics in the Cambridge Tripos, and has no better justification than that Euclid and Archimedes wrote in Greek.

Science is the Experimental Method. The recognition of the importance of experiment was the key event in the history of Science. The Baconian thesis was sound; we can often do no better today than to follow it.

Yet this definition is incomplete in several respects. It arbitrarily excludes pure mathematics, and needs to be supplemented to take cognizance of those perfectly respectable sciences such as Astronomy or Geology where we can only observe the consequences of events and circumstances over which we have no control. It also fails to give due credit to the strong theoretical and logical sinews that are needed to hold the results of experiments and observations together and give them force. Scientists do not in fact work in the way that operationalists suggest; they tend to look for, and find, in Nature little more than they believe to be there, and yet they construct airier theoretical systems than their actual observations warrant. Experiment distinguishes Science from the older, more speculative ways to knowledge but it does not fully characterize the scientific method.

Science arrives at Truth by logical inferences from empirical observations. This is the standard type of definition favored by most serious philosophers. It is usually based upon the principle of induction-that what has been seen to happen a great many times is almost sure to happen invariably and may be treated as a basic fact or Law upon which a firm structure of theory can be erected.

There is no doubt that this is the official philosophy by which most practical scientists work. From it one can deduce a number of practical procedures, such as the testing of theory by 'predictions' of the results of future observations, and their subsequent confirmation. The importance of speculative thinking is recognized, provided that it is curbed by conformity to facts. There is no restriction of a metaphysical kind upon the subject matter of Science, except that it must be amenable to observations and inference.

But the attempt to make these principles logically watertight does not seem to have succeeded. What may be called the positivist program, which would assign the label 'True' to statements that satisfy these criteria, is plausible but not finally compelling. Many philosophers have now sadly come to the conclusion that there is no ultimate procedure which will wring the last drops of uncertainty from what scientists call their knowledge.

And although working scientists would probably state that this is the Rule of their Order, and the only safe principle upon which their discoveries may be based, they do not always obey it in practice. We often find complex theories-quite good theories that really depend on very few observations. It is, extraordinary, for example, how long and complicated the chains of inference are in the physics of elementary particles; a few clicks per month in an enormous assembly of glass tubes, magnetic fields, scintillator fluids and electronic circuits becomes a new 'particle', which in its turn provokes a flurry of theoretical papers and ingenious interpretations. I do not mean to say that the physicists are not correct; but no one can say that all the possible alternative schemes of explanation are carefully checked by innumerable experiments before the discovery is acclaimed and becomes part of the scientific canon. There is far more faith, and reliance upon personal experience and intellectual authority, than the official doctrine will allow.

A simple way of putting it is that the logico-inductive scheme does not leave enough room for genuine scientific error. It is too black and white. Our experience, both as individual scientists and historically, is that we only arrive at partial and incomplete truths; we never achieve the precision and finality that seem required by the definition. Thus, nothing we do in the laboratory or study is "really" scientific, however honestly we may aspire to the ideal. Surely, it is going too far to have to say, for example, that it was "unscientific" to continue to believe in Newtonian dynamics as soon as it had been observed and calculated that the rotation of the perihelion of Mercury did not conform to its predictions.

This summary of the various conceptions of science obviously fails to do justice to the vast and subtle literature on the subject. If I have emphasized the objections to each point of view, this is merely to indicate that none of the definitions is entirely satisfactory. Most practicing scientists and most people generally, take up one or other of the attitudes that I have sketched, according to the degree of their intellectual sophistication-but without fervor. One can be zealous, for Science, and a splendidly successful research worker, without pretending to a clear and certain notion of what Science really is. In practice it does not seem to matter.

Perhaps this is healthy. A deep interest in theology is not welcome in the average churchgoer, and the ordinary taxpayer should not really concern himself about the nature of sovereignty or the merits of bicameral legislatures. Even though Church and State depend, in the end, upon such abstract matters, we may reasonably leave them to the experts if all goes smoothly. The average scientist will say that he knows from experience - and common sense what he is doing, and so long as he is not striking too deeply into the foundations of knowledge he is content to leave the highly technical discussion of the nature of Science to those self-appointed authorities the Philosophers of Science. A rough and ready conventional wisdom will see him through.

Yet in a way this neglect of - even scorn for - the Philosophy of Science by professional scientists is strange. They are, after all, engaged in a very difficult, rather abstract, highly intellectual activity and need all the guidance they can from general theory. We may agree that the general principles may not in practice be very helpful, but we might have thought that at least they would be taught to young scientists in training just as medical students are taught Physiology and budding administrators were once encouraged to acquaint themselves with Plato's Republic. When the student graduates and goes into a laboratory, how will he know what to do to make scientific discoveries if he has not been taught the distinction between a scientific theory and a non-scientific one? Making all allowances for the initial prejudice of scientists against speculative philosophy, and for the outmoded assumption that certain general ideas would communicate themselves to the educated and cultured man without specific instruction, I find this an odd and significant phenomenon.

The fact is that scientific investigation, as distinct from the theoretical content of any given branch of science, is a practical art. It is not learnt out of books, but by imitation and experience. Research workers are trained by apprenticeship, by working for their PhDs under the supervision of more experienced scholars, not by attending courses in the metaphysics of physics. The graduate student is given his "problem": "You might have a look at the effect of pressure on the band structure of the III-V compounds; I don't think it has been done yet, and it would be interesting to see whether it fits into the pseudopotential theory." Then, with considerable help, encouragement and criticism, he sets up his apparatus, makes his measurements, performs his calculations, etc. and in due course writes a thesis and is accounted a qualified professional. But notice that he will not at any time have been made to study formal logic, nor will he be expected to defend his thesis in a step b step deductive procedure. His examiners may ask him, why he had made some particular assertion in the course of his argument, or they may enquire as to the reliability of some particular measurement. They may even ask him to assess the value of the "contribution" he has made to the subject as a whole. But they will not ask him to give, any opinion as to whether Physics is ultimately true, or whether he is justified now in believing in an external world, or in what sense a theory is verified by the observation of favorable instances. The examiners will assume that the candidate shares with them the common language and principles of their discipline. No scientist really doubts that theories are verified by observation, any more than a Common Law judge hesitates to rule that hearsay evidence is inadmissible.

What one finds in practice is that scientific argument, written or spoken, is not very complex or logically precise. The terms and concepts that are used may be extremely subtle and technical, but they are put "together in quite simple logical forms, with expressed or implied relations as the machinery of deduction. It is very seldom that one uses the more sophisticated types of proof used in Mathematics, such as asserting a proposition by proving that its negation implies a contradiction. Of course actual mathematical or numerical analysis of data may carry the deduction through many steps, but the symbolic machinery of algebra and the electronic circuits of the computer are then relied on to keep the argument straight. (This point I owe to Professor Korner.) In my own experience, one more often detects elementary non sequiturs in the verbal reasoning than actual mathematical mistakes in the calculations that accompany them. This is not said to disparage the intellectual powers of scientists; I mean simply that the reasoning used in scientific papers is not very different from what we should use in an everyday careful discussion of an everyday problem.

This is a point to which we shall return in a later chapter. It is made here to emphasize the inadequacy of the 'logico-inductive' metaphysic of Science. How can this be correct ' when few scientists are interested in or understand it, and none ever uses it explicitly in his work? But then if Science is distinguished from other intellectual disciplines neither by a particular style or argument nor by a definable subject matter, what is it?

The answer proposed in this essay is suggested by its title: Science is Public Knowledge. This is, of course, a very cryptic definition, with almost the suggestion of a play upon words. (There is also, unfortunately, the hint of an antithesis to Personal Knowledge, the title of Polanyi's book to which I have already referred. No antagonism is meant. Polanyi goes a long way along the path I follow, and is one of the few writers on Science who have seen the social relations between scientists as a key factor in its nature.) What I mean is something along the following lines. Science is not merely published knowledge or information. Anyone may make an observation, or conceive a hypothesis, and, if he has the financial means, get it printed and distributed for other persons to read. Scientific knowledge is more than this. Its facts and theories, must survive a period of critical study and testing by other competent and disinterested individuals, and must have been found so persuasive that they are almost universally accepted. The objective of Science is not just to acquire information nor to utter all non-contradictory notions; its goal is a consensus of rational opinion over the widest possible field.

In a sense, this is so obvious and well-known that it scarcely needs, saying. Most educated and informed people agree that Science is true, and therefore impossible to gainsay. But I assert my definition much more positively; this is the basic principle upon which Science is founded. It is not a subsidiary consequence of the "Scientific Method"; it is the scientific method itself.

The defect of the conventional philosophical approach to Science is that it considers only two terms in the equation. The scientist is seen as an individual, pursuing a somewhat one-sided dialogue with taciturn Nature. He observes phenomena, notices regularities, arrives at generalizations, deduces consequences, etc., and eventually, Hey Presto! A Law of Nature springs into being. But it is not like that at all. The scientific enterprise is corporate. It is not merely, in Newton's incomparable phrase that one stands on the shoulders of giants, and hence can see a little farther. Every scientist sees through his own eyes - and also through the eyes of his predecessors and colleagues. It is never one individual that goes through all the steps in the logico-inductive chain; it is a group of individuals, dividing their labor but continuously and jealously checking each other's contributions. The cliché of scientific prose betrays itself "Hence we arrive at the, conclusion that..." 'The audience to which scientific publications are addressed
is not passive; by its cheering or booing, its bouquets or brickbats, it actively controls the substance of the communications that it receives.

In other words, scientific research is a social activity. Technology, Art and Religion are perhaps possible for Robinson Crusoe, but Law and Science are not. To understand the nature of Science, we must look at the way in which scientists behave towards one another, how they are organized and how information passes between them. The young scientist does not study formal logic, but he learns by imitation and experience a number of conventions that embody strong social relationships. In the language of Sociology, he learns to play his role in a system by which knowledge is acquired, sifted and eventually made public property.

It has, of course, long been recognized that Science is peculiar in its origins to the civilization of Western Europe. The question of the social basis of Science, and its relations to other organizations and institutions of our way of life is much debated. Is it a consequence of the 'Bourgeois Revolution', or of Protestantism - or what? Does it exist despite the Church and the Universities, or because of them? Why did China, with its immense technological and intellectual resources, not develop the same system? What should be the status of the scientific worker in an advanced society; should he be a paid employee, with a prescribed field of study, or an aristocratic dilettante? How should decisions be taken about expenditure on research? And so on.

These problems, profoundly sociological, historical and political though they may be, are not quite what I have in mind. Only too often -the element in the argument that gets the least analysis is the actual institution about which the whole discussion hinges scientific activity itself. To give a contemporary example, there is much talk nowadays about the importance of creating more effective systems for storing and indexing scientific literature, so that every scientist can very quickly become aware of the relevant work of every other scientist in his field. This recognizes that publication is important, but the discussion usually betrays an absence of careful thought about the part that conventional systems of scientific communication play in sifting and sorting the material that they handle. Or again, the problem of why Greek Science never finally took off from its brilliant taxiing runs is discussed in terms of, say, the aristocratic citizen despising the servile labor of practical experiment, when it might have been due to the absence of just such a communications system between scholars as was provided in the Renaissance by alphabetic printing. The internal sociological analysis of Science itself is a necessary preliminary to the study of the Sociology of Knowledge in the secular world.

The present essay cannot pretend to deal with all such questions. The 'Science of Science' is a vast topic, with many aspects. The very core of so many difficulties is suggested by my present argument-which Science stands in the region where the intellectual, the psychological and the sociological coordinate axes intersect. It is knowledge, therefore intellectual, conceptual and abstract. It is inevitably created by individual men and women, and therefore has a strong psychological aspect. It is public, and therefore molded and determined by the social relations between individuals. To keep all these aspects in view simultaneously, and to appreciate their hidden connections, is not at all easy. It has been put to me that one should in fact distinguish carefully between Science as a body of knowledge, Science as what scientists do and Science as a social institution. This is precisely the sort of distinction that one must not make; in the
language of geometry, a solid object cannot be reconstructed from its projections upon the separate Cartesian planes. By assigning the intellectual aspects of Science to the professional philosophers we make of it an and exercise in logic; by allowing the psychologists to take possession of the personal dimension we overemphasize the mysteries of "creativity" at the expense of rationality and the critical power of well-ordered argument; if the social aspects are handed over to the sociologists, we get a description of research as an N-person game, with prestige points for stakes and priority claims as trumps. The problem has been to discover a unifying principle for Science in all its aspects. The recognition that scientific knowledge must be public and consensible (to coin a necessary word) allows one to trace out the complex inner relationships between its various facets. Before one can distinguish and discuss separately the philosophical, psychological or sociological dimension of Science, one must somehow have succeeded in characterizing it as a whole. ("Hence a true philosophy of science must be a philosophy of scientists and laboratories as well as one of waves, particles and symbols." Patrick Meredith in Instruments of Communication, P. 40.)

In an ordinary work of Science one does well not to dwell too long on the hypothesis that is being tested, trying to define and describe it in advance of reporting the results of the experiments or calculations that are supposed to verify or negate it. The results themselves indicate the nature of the hypothesis, its scope and limitations. The present essay is organized in the same manner. Having sketched a point of view in this chapter, I propose to turn the discussion to a number of particular topics that I think can be better understood when seen from this new angle. To give a semblance of order to the argument, the various subjects have been arranged according to whether they are primarily intellectual, for example, some attempt to discriminate between scientific and non-scientific disciplines; psychological - e.g. the role of education, the significance of scientific creativity; sociological - the structure of the scientific community and the institutions by which it maintains scientific standards and procedures. Beyond this classification, the succession of topics is likely to be pretty haphazard; or, as the good lady said, "How do I know what I think until I have heard what I have to say?"

The subject is indeed endless. As pointed out in the Preface, the present brief essay is meant only as an exposition of a general theory, which will be applied to a variety of more specific instances in a larger work. The topics discussed here are chosen, therefore, solely to exemplify the main argument, and are not meant to comprehend the whole field. In many cases, also, the discussion has been kept abstract and schematic, to avoid great marshlands of detail. The reader is begged, once more, to forgive the inaccuracies and imprecisions inevitable in such an account, and to concentrate his critical attention upon the validity of the general principle and its power of explaining how things really are.

Welcome to AP Biology

You are reading this post because you were invited to the blog and accepted - Welcome. The Mariner AP Biology blog will serve as a place to receive assignments, discuss biology with your classmates, ask me questions, and more as we think of uses. Before we begin with the summer assignments I want to share with you a quote by Peter Dorman on the blog Econospeak -

"A part of our paralysis, however, can be chalked up to the fact that the twentieth century’s most important cognitive revolution, the shift from deterministic to probabilistic thinking, is still confined to a tiny sliver of the population. …Don’t worry about the warning label on the package: smoking can’t cause cancer because I know someone who is almost 90, in great health and still smokes a pack a day. …Thinking probabilistically isn’t something we’re born with. It has to be taught; in fact it has to be taught over and over because it seems to go against our natural cognitive tendencies. A lot of readers of this blog (insofar as a high percentage of a low number can be “a lot”) are teachers. Whatever your subject, there is no more important goal you can strive for."

Put another way, the universe plays dice. Science helps us game the system by showing us how the dice are loaded. If you are truly interested in a future in the sciences, learn this. A significant portion of this course will be focused on doing science and that relies on probability and statistics.

Comments?

Check in soon for your first summer assignment.

Mr. Baker