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\Medawar, P. B. Is The Scientific Paper a Fraud? Experiment: A Series of Scientific Case
Histories First Broadcast in the BBC Third Programme, David Edge, editor. London: British
Broadcasting Corporation, 1964, pp. 7-13.\
I have chosen for my title a question: Is the scientific paper a fraud? I ought to explain that a
scientific ‘paper' is a printed communication to a learned journal, and scientists make their work
known almost wholly through papers and not through books, so papers are very important in
scientific communication. As to what I mean by asking ‘is the scientific paper a fraud? - I do not
of course mean ‘does the scientific paper misrepresent facts,' and I do not mean that the
interpretations you find in a scientific paper are wrong or deliberately mistaken. I mean the
scientific paper may be a fraud because it misrepresents the process of thought that accompanied
or gave rise to the work that is described in the paper. That is the question, and I will say right
away that my answer to it is ‘yes.' The scientific paper in its orthodox form does embody a
totally mistaken conception, even a travesty, of the nature of scientific thought.
Just consider for a moment the traditional form of a scientific paper (incidentally, it is a form
which editors themselves often insist upon). The structure of a scientific paper in the biological
sciences is something like this. First, there is a section called the ‘introduction' in which you
merely describe the general field in which your scientific talents are going to be exercised,
followed by a section called ‘previous work' in which you concede, more or less graciously, that
others have dimly groped towards the fundamental truths that you are now about the expound.
The a section on ‘methods - that is O.K. Then comes the section called ‘results.' The section
called ‘results' consists of a stream of factual information in which it is considered extremely bad
form to discuss the significance of the results you are getting. You have to pretend that you mind
is, so to speak, a virgin receptacle, an empty vessel, for information which floods into it from the
external world for no reason which you yourself revealed. You reserve all appraisal of scientific
evidence until the ‘discussion,' and in the discussion you adopt the ludicrous pretence of asking
yourself if the information you have collected actually means anything; of asking yourself if any
general truths are going to emerge from the contemplation of all the evidence you brandished in
the section called ‘results.'
Of course, what I am saying is rather an exaggeration, but there is more than a merely element of
truth in it. The conception underlying this style of scientific writing is that scientific discovery is
an inductive process. What induction implies in its cruder form is roughly speaking this:
scientific discovery, or the formulation of scientific theory, starts with the unvarnished and
unembroidered evidence of the senses. It starts with simple observation - simple, unbiased,
unprejudiced, naive, or innocent observation - and out of this sensory evidence, embodied in the
form of simple propositions or declaration of fact, generalizations will grow up and take shape,
almost as if some process of crystallization or condensation were taking place. Out of a
disorderly array of facts, an orderly conception of scientific discovery in which the initiative
comes from the unembroidered evidence of the senses was mainly the work of a great and wise,
but in this context, I think, very mistaken man - John Stuart Mill.
John Stuart Mill saw, as of course a great many others had seen before him, including Bacon, that
deduction in itself is quite powerless as a method of scientific discovery - and for this simple
reason: that the process of deduction as such only uncovers, brings out into the open, makes
explicit, information that is already present in the axioms or premises from which the process of
deduction started. The process of deduction reveals nothing to us except what the infirmity of our
own minds had so far concealed from us. It was Mill's belief that induction was the method of
science - ‘that great mental operation,' as he called it, ‘the operation of discovering and proving
general propositions.' And around this conception there grew up an inductive logic, of which the
business was ‘to provide rules to which, inductive arguments conform, those arguments are
conclusive.' Now, John Stuart Mill's deeper motive in working out what he conceived to be the
essential method of science was to apply that method to the solution of sociological problems: he
wanted to apply to sociology the methods which the practice of science had shown to be
immensely powerful and exact.
It is ironical that the application to sociology of the inductive method, more or less in the form in
which Mill himself conceived it, should have been an almost entirely fruitless one. The simplest
application of the Millsian process of induction to sociology came in a rather strange movement
called Mass Observation. The beliefs underlying Mass Observation was apparently this: that if
one could only record and set down the actual raw facts about what people do and what say in
pubs in trains, when they make love to each other, when they are playing games, and so on, then
somehow, from this wealth of information, a great generalization would inevitably emerge. Well,
in point of fact, nothing important emerged from this approach, unless somebody's been holding
out of me. I believe the pioneers of Mass Observation were ornithologists. Certainly they were
man-watching - were applying to sociology the very methods which had done so much to bring
ornithology into disrepute.
The theory underlying the inductive method cannot be sustained. Let me give three good reasons
why not. In the first place, the starting point of induction, naive observation, innocent
observation, is a mere philosophic fiction. There is no such thing as unprejudiced observation.
Every act of observation we make is biased. What we see or otherwise sense is a function of what
we have seen or sensed in the past.
The second point is this. Scientific discovery or the formulation of the scientific idea on the one
hand, and demonstration or proof on the other hand, are two entirely different notions, and Mill
confused them. Mill said that induction was the ‘operation of discovering and proving general
propositions,' as if one act of mind would do for both. Now discovery and proof could depend on
the same act of mind, and in deduction they do. When we indulge in the process of deduction - as
in deducing a theorem from Euclidian axioms or postulates - the theorem contains the discovery
(or, more exactly, the uncovery of something which was there in the axioms and postulates,
thought it was no actually evident) and process of deduction itself, if it has been carried out
correctly, is also the proof that the ‘discovery' is valid, is logically correct. So in the process of
deduction, discovery and proof can depend on the same process. But in scientific activity they are
not the same thing - they are, in fact, totally separate acts of mind.
But the most fundamental objection is this. It simply is not logically possible to arrive with
certainty at any generalization containing more information than the sum of the particular
statements upon which that generalization was founded, out of which it was woven. How could a
mere act of mind lead to the discovery of new information? It would negate a law as fundamental
as the law of conservation of matter: it would violate the law of conservation of information.
In view of all these objections, it is hardly surprising that Bertrand Russell in a famous footnote
that occurs in his Principles of Mathematics of 1903 should have said that, so far as he could see,
induction was a mere method of making plausible guesses. And our greatest modern authority on
the nature of scientific method, Professor Karl Popper, has no use for induction at all: he regards
the inductive process of thought as a myth. ‘There is no need even to mention induction,' he says
in his great treatise, on The Logic of Scientific Discovery - though of course he does.
Now let me go back to the scientific papers. What is wrong with the tradition form of scientific
paper is simply this: that all scientific work of an experimental or exploratory character starts
with some expectation about the outcome of the inquiry and governs its actual form. It is in the
light of this expectations that some observations are held relevant and others not; that some
methods are chosen, others discarded; that some experiments are done rather than others. It is
only in the light of this prior expectation that the activities the scientist reports in his scientific
papers really have any meaning at all.
Hypotheses arise by guesswork. That is to put it in its crudest form. I should say rather that they
arise by inspiration; but in any event they arise by processes that form part of the subject-matter
of psychology and certainly not of logic, for their is no logically rigorous method for devising
hypotheses. It is a vulgar error, often committed, to speak of ‘deducing' hypotheses. Indeed one
does not deduce hypotheses: hypotheses are what one deduces things from. So the actual
formulation of a hypothesis is - let us say a guess; is inspirational in character. But hypotheses
can be tested rigorously - they are tested by experiment, using the word ‘experiment' in a rather
general sense to mean an act performed to test a hypothesis, that is, to test the deductive
consequences of a hypothesis. If one formulates a hypothesis, one can deduce from it certain
consequences which are predictions or declarations about what will, or with not, be the case. If
these predictions and declarations or mistaken, then the hypothesis must be discarded, or at least
modified. If, on the other hand, the predictions turn out correct, then the hypothesis has stood up
to trial, and remains on probation as before. This formulation illustrates very well, I think, the
distinction between on the one hand the discovery or formulation of a scientific idea or
generalization, which is to a greater or lesser degree an imaginative or inspirational act, and on
the other hand the proof, or rather the testing of a hypothesis, which is indeed a strictly logical
and rigorous process, based upon deductive arguments.
This alternative interpretation of the nature of the scientific process,s of the nature of scientific
method, is sometimes called the hypothetico-deductive interpretation and this is the view which
Professor Karl Popper in the Logic of Scientific Discovery has persuaded us is the correct one.
To give credit where credit is surely due, it is proper to say that the first professional scientist to
express a fully reasoned opinion upon the way scientists actually think where they come upon
their scientific discoveries - namely William Whewell, a geologist, and incidentally the Master of
Trinity College, Cambridge - was also the first person to formulate this hypothetico-deductive
interpretation of scientific activity. Whewell, like his contemporary Mill, wrote at great length -
unnecessarily great length, one is nowadays inclined to think - and I cannot recapitulate his
argument, but one or two quotations will make the gist of this thought clear. He said: ‘An art of
discovery is not possible. We can give no rules for the pursuit of truth which should be
universally and peremptorily applicable.' And of hypotheses, he said, with great daring - why it
was daring I will explain in just a second - ‘a facility in devising hypotheses, so far from being a
fault in the intellectual character of a discoverer, is a faculty indispensable to his task.' I said this
was daring because the word ‘hypothesis' and the conception it stood for was still in Whewell's
day a rather discreditable one. Hypotheses had a flavor about them of what was wanton and
irresponsible. The great Newton, you remember, had frowned upon hypothesis. ‘Hypotheses non
fingo,' he said, and this is another version in which he says ‘hypotheses non sequor - I do not
pursue hypotheses.
So to go back once again to the scientific paper: the scientific paper is a fraud in the sense that it
does given a totally misleading narrative of the process of thought that go into the making of
scientific discoveries. The inductive format of the scientific paper should be discarded. The
discussion which in the traditional scientific paper goes last should surely come at the beginning.
The scientific facts and scientific acts should follow the discussion, and scientists should not be
ashamed to admit, as many of them apparently are ashamed to admit, that hypotheses appear in
their minds along uncharted by-ways of thought; that they are imaginative and inspiration in
character; that they are indeed adventures of the mind. What, after all, is the good of scientists
reproaching others for their neglect of, or indifference to, the scientific style of thinking they set
such great store by, if their own writings show that they themselves have no clear understanding
of it?
Anyhow, I am practicing what I preach. What I have said about the nature of scientific discovery
you can regard as being itself a hypothesis, and the hypothesis comes where I think it should be,
namely, it comes at the beginning of the series. Later speakers will provide the facts which will
enable you to test and appraise this hypothesis, and I think you will find - I hope you will find -
that the evidence they will produce about the nature of scientific discovery will bear me out.
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