Where Do Hypotheses Come From?
WE ALL MAKE THEM
In this chapter we turn to the
question, where do we get scientific hypotheses? The way the question is phrased may be
misleading. Put this way, it
gives the impression that forming hypotheses is something, unique to scientific activity. However, if we
understand a hypothesis as the perception .of some pattern in phenomena, the
establishment of some expectation as
to what will happen next, we realize that "forming hypotheses" is something we do, all the time
and have been doing since birth. We are by nature hypothesis formers. At what
age our practice of interpreting, the World in such structured terms begins is not known, but long before we learn to talk in
sentences we have already gone far beyond the raw impressions given us by our senses. We
organize things coherently into such concepts as "mother," "father,"
"food," and "doggy," each of which implies a whole
complex set of recognitions and expectations.
We are not
normally aware of how much of what we "see" is seen' by inference and memory
rather than with just our eyes. But there are occasions when this is brought home to us, as we
discussed in Chapter 2, by. the
study of the kinds of optical illusions favored by psychologists and the puzzle pages
of newspapers, by encounters with people of different cultures, by occasions where
something radically unexpected happens when, in the graphic but hackneyed phrase, "our whole world collapses about
us."
In making the statement that what we perceive as
reality is actually
Hypothesis, the result of a
culturally and personally determined interaction between ourselves and what
is out there, we are not arguing that there is a discrepancy between
"reality” and what we think is reality. Rather we are saying there is no
reality different from our perceptions of it. We cannot adopt a critical
attitude toward everything we think we know; we couldn't function in
the world if we did. But it is not surprising that, even in situations where
some serious discordance has appeared between our expectations and what actually
happens, we should cling to the ways of thinking and perceiving that we are used to. The discovery of new hypotheses in
science or in daily life is difficult because it is not so much a question of
finding a new pattern where none was previously seen but rather of replacing a pattern we
are used to-so used to that we take for granted that it is really there-by a new one.
The point
was put very well by Josh Billings: -"It aint ignorance that
hurts us,
it's what
we know that aint so!"(1)
We are not trying to suggest that conservatism in ideas
is wrong. It is impossible to subject
everything we believe to doubt, and it is
reasonable, when faced with new problems, to try to cope with them by the methods
we have found to work with old ones. Since not all problems have easy answers, we would be foolish to assume
that because our accustomed methods don't seem to work right off the bat
they must be wrong and should be discarded.
Today we "know" that
the world is round. But we should be sympathetic to our ancestors who
refused to believe it. It flies in the face of common sense: a wealth of
experience with falling off of things like trees, rocks, and steep hills
tells us that if the world were round one would fall off the other side.
We know better now, because we have been taught differently, but the first men to
conjecture that the world might be round did not have this advantage. They had to make an imaginative leap beyond the "facts" known by
everyone, and see things in a completely new way. Even today, a child told for
the first time that the world is round is startled and skeptical.
Because scientific discovery has
this character, one should not be surprised to learn that it is not a routine, mechanical process but
rather one in which the subconscious mind
plays a part (as it does in artistic creativity,
also) and that chance and circumstance contribute. There is a popular but
completely misleading belief about scientific discovery, that it is an orderly process in which facts are
patiently gathered and neatly arranged, at which time the scientist sits
down and contemplates them until some new
pattern emerges. One can contrast this tidy picture with a quotation we have
given earlier from the chemist Kekule
describing the dreamlike reverie
during which the dancing images of the atoms ,images, of course, arising from his own unconscious
mind-forced the new concept into conscious awareness
THE MOMENT OF INSIGHT
Figure
21..
The act of discovery as a flash of
insight rather than the patient
Assembling of the pieces of a jigsaw puzzle is
shown beautifully by the following episode, described by the psychologist W.
Kohler (2):
Nueva [a young female chimpanzee] was tested 3 days
after her arrival. ... She had not yet made the acquaintance of the other
animals but remained isolated in a
cage. A little stick is introduced into her cage; she scrapes the ground with it, pushes the banana
skins together in a heap, and then
carelessly drops the stick at a distance of about three-quarters of a metre from the bars. Ten minutes later, fruit is
placed outside the cage beyond her
reach. She grasps at it, vainly of course, and then begins the characteristic complaint of the chimpanzee; she
thrusts both lips especially the lower-forward, for
a couple of inches, gazes imploringly at the observer, utters whimpering
sounds, and finally flings herself on to the ground on her back-a gesture
most eloquent of despair, which may
be observed on other occasions as
well. Thus, between lamentations and entreaties, some time passes, until--about seven
minutes after the fruit has been exhibited to her-she-suddenly casts a look at
the stick, ceases her moaning, seizes the stick, stretches it out of the cage, and
succeeds, though somewhat clumsily, in drawing the bananas within arm's length.
Moreover,
Nueva at once puts the end of her stick behind and beyond her objective. The test is repeated
after an hour's interval; on this second occasion, the animal has recourse
to the stick much sooner, and uses it with more skill; and at a third repetition, the stick
is used immediately, as on all subsequent occasions. (pp. 32-33)
Another example of the role of the unconscious mind in discovery is given in a description by the
French mathematician Poincare of his discoveries of some new lasses of mathematical functions and their properties. One does not need
to understand "Fuchsian functions" or other mathematical terms used by Poincare to appreciate his story (3):
It is time to penetrate deeper
and to see what goes on in the very soul of the mathematician. For this, I believe, I can do best
by recalling memories of my own. But I shall limit
myself to telling how I wrote my first memoir on Fuchsian functions. I beg the reader's pardon; I am
about to use some technical
expressions, but they need not frighten him, for he is not obliged to understand them. I shall say, for example, that
I have found the demonstration of
such a theorem under such circumstances. This theorem will have a barbarous name, unfamiliar to many, but that
is unimportant, what is of interest for
the psychologist is not the theorem but the circumstances.
For fifteen days I strove to prove
that there could not be any functions like those I have since called Fuchsian functions. I was
then very ignorant; every day I seated myself at my work table, stayed an hour or two, tried
a great number
of combinations and reached no results. One evening, contrary to my custom, I drank black
coffee and could not sleep. Ideas rose in crowds; I felt them collide until
pairs interlocked, so to speak, making a
Stable
combinations.
By the next morning i had established the existence of-a class of Fuchsian functions, those which come from
the hyper geometric series; I had only to write out the results, which took but a few
hours....
Just at this time I left Caen, where I was then
living, to go on a geologic excursion under the auspices of the school of mines. The
changes of
travel made me forget my mathematical work. Having reached Courtances, we entered an omnibus to go some place or other. At the moment when I put my foot on the step the idea came to me, without anything in my former
thoughts seeming to have paved the way for it, that the transformations I. had used to define the Fuchsian
functions were identical with those of
non-Euclidean geometry. I did not verify the idea, I should not have had, time. as, upon taking my seat in the omnibus, I went on with a conversation already commenced, but I felt a perfect
certainty. On my return to Caen, for conscience's sake I verified the result at my
leisure... (pp.
52-55)
POETRY ALSO
The similarity of the process to other creative
activities, such as the writing of poetry,
is shown by this quotation from A. E. Houseman(4):
In short I think that the production of
poetry, in its first stage, is less an active than a passive and
involuntary process; and if I were obliged, not to define poetry, but to name
the class of things to which it belongs, I should call it a secretion; whether a natural
secretion, like turpentine in the fir, or a morbid secretion, like the
pearl in the oyster. I think that my own case, though I may not deal with the
material so cleverly as the oyster does, is the latter, because I have seldom
written poetry unless I was rather out of health, and the experience,
though pleasurable, was generally agitating and exhausting. If only that you
may, know what to avoid, I will give some account of the process.
Having drunk a pint of beer at
luncheon-beer is a sedative to the brain, and my afternoons are the least intellectual
portion of my life--I would go out for a walk of two or three hours. As I
went along, thinking of nothing in particular, only looking at things around
me and following the progress of the seasons, there would flow into my
mind, with sudden and unaccountable emotion sometimes a line or two of
verse, sometimes a whole stanza at once, accompanied, not preceded, by a vague
notion of the poem which they were destined to form part of. Then there would usually be a lull of an hour or
so, then perhaps the spring would bubble up again. I say bubble up, because so far as I could make out, the
source of the suggestions
thus proffered to the brain was an abyss which I have already had occasion to mention, the pit
of the stomach. When I got home I wrote them down, leaving gaps, and
hoping that further inspiration might be forthcoming another day.
Sometimes it was, if I took my walks in a receptive and expectant frame of mind; but sometimes the
poem had to be taken in hand and completed
by the brain, which was apt to be a matter of trouble and anxiety, involving trial and disappointment, and sometimes ending
in failure. I happen to remember distinctly the genesis of the piece which stands last in my first volume. Two of the stanzas, I do not say which, came into my head, just as they are printed,
while I was crossing the comer of Hampstead Heath between Spaniard's Inn and
the footpath to
Temple Fortune. A third stanza came with a little coaxing after tea. One more was needed, but it did not
come: I had to turn to and compose it myself, and that was a laborious business. I wrote it
thirteen times, and it was more than a twelvemonth before I got it right.
(pp. 47-50)
FOLK WISDOM
Not all
discoveries have arisen unexpectedly out of the subconscious of the discoverers.
There are a number of examples where ideas were in the air, so to speak,
or present in the form of folk beliefs. The achievement of the discoverer was
to take them seriously and think of ways to test them experimentally. Snow was not the
first to think of the water supply as a mode of transmission of cholera: he
states in his book that a number of people had suggested this possibility, some of whom were professionals actively
concerned with finding the cause of the disease and others just ordinary
people expressing a conviction they derived from their own experiences.
Snow's genius was to think of experiments that could prove it.
Jenner learned the idea that the
mild disease of cowpox might confer immunity against smallpox from the milkmaids who
often caught cowpox
from the cows they milked. Jenner took this apparent superstition of uneducated people
seriously enough to test it, even though it required taking the risk of deliberately infecting
people with a disease in the hope of preventing a more serious one. He had to
fight violent opposition
in his program: there are contemporary cartoons showing people growing cow's heads (see
Figure 22) from their shoulders at the site of the inoculation.
Figure
22
FIGURE 22. The Cow
Pock." Etching by James Gillray, 1802. The physidan performing the vaccination is a portrait of Jenner.
(From the Smith, Kline, and French Laboratories collection of the Philadelphia
Museum of Art, and reproduced with the
permission of the Museum.) One of the first conclusive
demonstrations that the bite of an insect is capable of transmitting disease was by
Theobald Smith and E. L. Kilborne in the case of
Texas
cattle fever in
1893. This
work
led to the identification of insect
transmission of such diseases as malaria, bubonic plague, and yellow fever. Smith and Kilborne did not
make the hypothesis
themselves that the ticks that bite the cows transmit the disease; it was the cattle ranchers that concluded
this. They had noticed a relation between the onset of
tick infestations and the appearance of the disease in their cattle.(6)
CHANCE
Sometimes, although more rarely
than one might think, discoveries
are made by accident. The
following is an example reported by A. V. Nalbandov(7):
In 1940 I became interested in
the effects of hypophysectomy of chickens. After I had mastered the surgical
technique my birds continued to die and within a few weeks after the operation none
remained alive. Neither replacement therapy nor any other precautions taken
helped and I was about ready to agree with A. S. Parkes and R. T. Hill who had done
similar operations
_in_ England, that hypophysectomized chickens simply cannot live. I resigned
myself to doing a few short-term experiments and dropping the whole project when
suddenly 98% of a group of hypophysectornized birds survived for 3 weeks and a
great many lived for as long as 6 months. The only explanation I
could find was that my surgical technique had improved with practice. At about
this time, and when I was ready to start a
long-term experiment, the birds again started dying and within a week both recently operated birds and those which
had lived for several months were
dead. This, of course, argued against surgical proficiency. I continued
with the project since i now
knew that they could live under some circumstances which, however, eluded me
completely. At about this time I had a second successful period during which
mortality was very low. But, despite careful analysis of records (the
possibility of disease and many other factors were considered and eliminated) no
explanation was apparent. You can imagine how frustrating it was to be unable to take advantage of something that was
obviously having a profound effect on the ability of these animals to withstand
the operation. Late one night I was driving home from a party via a road which passes
the laboratory. Even though it was 2 A.M. lights were burning in the animal
rooms. I thought
that a careless student had left them on so I stopped to turn them off. A few nights later I noted
again that lights had been left on all night. Upon enquiry it turned out that a
substitute janitor, whose job it was to make sure at midnight that all
the windows were closed and doors locked, preferred to leave on the lights
in the animal room in order to be able to find the exit door (the light
switches not being near the door). Further
checking showed that the two
survival periods coincided with the times when the substitute janitor was
on the job. Controlled experiments soon
showed that hypophysectomized
chickens kept in darkness all died while chickens lighted for 2 one-hour
periods nightly lived indefinitely. The
explanation was that birds in the
dark do not eat and develop hypoglycaemia from which they cannot recover, while birds
which are lighted
eat enough to prevent
hypoglycaemia. Since that time we no longer experience any trouble in
maintaining hypophysectomized birds for as long as we wish. (pp. 167-168)
Accident also played a part in
Semmeiweis's discovery that puerperal fever-childbed fever-which killed thousands of
women during childbirth
in hospitals in the nineteenth century, was transmitted by the hands of the doctors. These
doctors, who had previously examined women already sick with the disease or who had
performed autopsies on fatal cases, in accord with the practice of the time had washed but
not disinfected
their hands. Semmelweis made this discovery when he recognized symptoms similar to
childbed fever in a physician friend of his who died of "blood
poisoning" contracted from a scalpel wound incurred while performing an
autopsy(5).
However, the role of chance in
discovery is only part of the story the discoverer usually plays an active rather than a
passive role: he must recognize the significance of a chance event that most
others would ignore.
There is a famous quotation from Pasteur which sums this up: "Chance favors the prepared
mind." Sir Alexander Fleming discovered penicillin from his observation
that bacterial cultures on petri dishes were killed in the vicinity of mold colonies that
formed accidentally on the nutrient medium. Prior to
Fleming's work, this observation had been made thousands of times in bacteriological
laboratories. The response had been to throw the
mold-infected cultures out because they were no longer any good for growing bacteria.
THE LOST KEYS
These stories of scientific discovery may remind the
reader of such common experiences as misplacing the car keys and searching the house for an hour in mounting
frustration, finally giving up in disgust and going to work, where one suddenly
remembers, 2 hours later, while absorbed in some detail of the job, that one left them
on the shelf in the kitchen while drinking a second cup of coffee. Of course, sometimes the frantic search succeeds, and
sometimes the keys are never found at all.
THE COLLECTIVE UNCONSCIOUS
The above examples of the
importance of the unconscious in discovery may give the impression that
discovery itself is a very chancy business-a matter of having a person with the right
unconscious mind in the right place at the right time. It may seem like a miracle that anything has been discovered at all.
But our unconscious minds are not that independent of
our environments. Scientists share the
broader culture of their society as well as the subculture of their own field, and through these are exposed to all
sorts of influences and suggestions. They have been trained by senior members of their professions; they attend
lectures, have private discussions
with their colleagues, read papers and books, and so Forth. It is trite to say
that any individual is unique, but it is necessary to recognize how much each person shares with
the community. It is hard to document the many ways in which one's
ideas may be influenced or suggested by the ideas of others, but it is a. common
experience in science
and in
life to pick
up ideas from others and without deliberate dishonesty come to believe that one thought of them
oneself.
There have been many remarkable
examples in the history of science where important discoveries were made almost
simultaneously and independently by several scientists. Newton and Leibniz both invented
the calculus at about the same time, and disputed for the rest of their lives about who deserved
credit for the discovery. In retrospect, the time must have been ripe for the
calculus to be discovered, although it would require a careful historical
study of the development of mathematics in the seventeenth century to show this. This
does not imply that it did not require genius to make the discovery at that
moment, but only that a century earlier not even a Newton or a Leibniz-could have done it, and by a century later, even
in their absence, the calculus would have been gradually developed by the efforts of many
lesser mathematicians.
Something similar happened in biology. Gregor Mendel
published a
paper in 1865 describing certain laws of heredity that he had discovered; his work was ignored until
1900, when the same laws were rediscovered simultaneously by three different groups of
scientists. Again, we can conclude that in 1900 the time was ripe for the acceptance of these laws: biology had advanced
in the 35 years from 1865 to 1900 in
ways that
made the subculture of biologists both more likely to discover them and more willing to accept
them.
THE TACTICS OF SCIENCE
The examples quoted above may
give a misleading impression about scientffic discovery in general. Poincare studying the problem of Fuchsian functions, Nalbandov trying
to keep alive chicks whose pituitary glands had been removed, and
Theobold Smith working on Texas cattle fever were scientists struggling with a problem and suddenly breaking through to a solution.
Many scientific discoveries are
made this way, but many are not. This may sound paradoxical: how can you solve problems
without struggling
with them? But science does not always progress by deliberate and direct ways. P.B. Medawar
uses a very appropriate military metaphor: problems do not always yield to direct
assault, sometimes they are solved by attrition, and sometimes they are outflanked.(8) Discoveries are often made and problems solved in
completely unexpected ways, by achievements in other fields that seem to
have no connection whatever with the problem at hand. It was not a biologist, a doctor, or an astronomer who invented the microscope or the
telescope, but grinders of lenses, who as far as we know were motivated only by idle curiosity or the desire for
amusement. But biology, medicine, and astronomy were revolutionized by these inventions.
The laws of Newton described very
accurately the motions of all the planets in their orbits around the sun except for Mercury, which showed certain slight deviations. Astronomers struggled
with the problem for years, proposing many hypotheses
in an attempt to show that if Newton's laws were properly applied the discrepancies
could be explained. None worked. Einstein, working on a completely different problem arising from certain peculiarities of the transmission of electromagnetic waves, was led to new laws of physics that replaced
Newton’s and explained the misbehavior of Mercury.
So it must be acknowledged that,
to make scientific discoveries, both genius and patient hard work are useful, but
neither is any guarantee of success. There is something about discovery
that cannot be programmed.
It is this unpredictable character
that makes it hard to know how to proceed, when aced with some deeply felt need. We want
to cure or, better
still, prevent cancer, how do we go about it? We can try to improve the tools at hand: better
methods of surgery or radiation treatment, earlier diagnosis, new drugs, a search for possible
environmental agents. But none of these may turn out to provide a real
solution. More fundamental understanding of cell biology may provide an answer, or it
may come unexpectedly from
completely unrelated areas: research on hay fever, insecticides, or abnormal psychology.
Choosing a problem and deciding
how to go about solving it are
Difficult. It isn't enough that
the problem should be important- it may not be solvable at the time, or
by the tactics proposed. Medawar has put it as follows
(8):
No scientist is admired for failing in the attempt to
solve problems that lie beyond
his competence. The most he can hope for is the kindly contempt earned by the Utopian politician.
If politics is the art of the possible, research is surely the art of the soluble. Both are
immensely practical minded
affairs. (p. 97)
REFERENCE NOTES
1. This quotation is apparently a paraphrase of Billings, who actually
said: "It is better tew know nothing
than tew know what aint so." We copied it when we saw it quoted somewhere we have lost track of. It is phrased
better that way for our purpose than the way Billings actually put it.
2. W. Kohler, The Mentality of Apes, Routledge & Kegan Paul, London, 1927 (reissued
1973). Reprinted with the permission of Routledge
& Kegan Paul.
3. Henri Poincare, Science and Method, Dover
Publications, New York, undated.
4. A. E. Houseman, The Name and Nature of Poetry, Cambridge University Press, Cam
bridge, 1933. Reprinted with the permission of
Cambridge University Press:
5. Harry Wain, A History of Preventive Medicine, Charles C Thomas, Springfield, I11., 1970. 6. H. Zinsser, Biographical
Memoirs of Theobald Smith, National Academy of
Sciences,
Washington, D.C., 1936.
7. W. I. Beveridge, The Art of Scientific Investigation, W. W. Norton & Co., Inc.; New York, 1950. Reprinted with permission of W. W. Norton and
Professor Beveridge. A paperback edition has been published by Vintage Books
(Random House. New York, undated).
8. P. B Medawar,
The Art of the Soluble, Pelican,
London, 1%9. Quoted with the permission
of Sir Peter Medawar.
SUGGESTED READING
Brewster Ghiselin, Ed., The Creative Process, University of
California Press, Berkeley,1952. Arthur Koestler, The Act of Creation, Macmillan, New York, 1964.
Tidak ada komentar:
Posting Komentar