6. As soon as an experimental result comes out against the prediction and
we arc satisfied that it is not a blunder we decide to consider the theory
falsified, but only tentatively so.
7. With this we gain a deeper understanding of our problem and proceed to
invent our next hypothetical theory for solving it, which we treat again in
the same way.
8. The concatenation of all these conjectures and refutations constitutes
the dynamics of scientific progress, moving ever closer to the truth, but
never reaching certainty.
In summary, the Popperian deductivist believes that science moves from
the general to the particulars and back to the general— a process without
end. Let me inject a metaphor. I might liken the Popperian view of science
to that of a carriage with two horses. The experimental horse is strong,
but blind. The theoretical horse can see, but it cannot pull. Only both
together can bring the carriage forward. And behind it leaves a track
bearing witness to the incessant struggle of trial and error.
The Deductive-inductive Method.
Just as money makes money, so knowledge already acquired facilitates the
acquisition of more knowledge. It is equally evident in the case of the
method, which will now engage our attention. The progress of science, and
of knowledge generally, is frequently facilitated by supplementing the
simpler inductive methods by deductive reasoning from knowledge already
acquired. Such a combination of deduction with induction, J. S. Mill called
the "Deductive Method," by which he really meant the "Deductive Method of
Induction." To avoid the confusion of the "Deductive Method" with mere
deduction, which is only one part of the whole method, it is better to
describe it as the "Deductive-Inductive Method" or the "Inductive-Deductive
Method." Mill distinguished two principal forms of this method as applied
to the study of natural phenomena, -namely, (1) that form of it in which
deduction precedes induction, and (2) that in which induction precedes
deduction. The first of these (1) he called the "Physical Method"; the
second (2) he called the "Historical Method."
These names are rather misleading, inasmuch as both forms of the method are
frequently employed in physics, where sometimes, say in the study of light,
mathematical (i.e., deductive) calculations precede and suggest physical
experiments (i.e., induction), and sometimes the inductive results of
observation or experiment provide the occasion or stimulus for mathematical
deductions. In any case, the differences in order of sequence are of no
great importance, and hardly deserve separate names. What is of importance
is to note the principal kinds of occasion, which call for the use of this
combined method. They are mainly three in number: (1) When an hypothesis
cannot be verified (i.e., tested) directly, but only indirectly; (2) when
it is possible to systematise a number of already established inductions,
or laws, under more comprehensive laws or theories; (3) when, owing to the
difficulties of certain problems, or on account of the lack of sufficient
and suitable instances of the phenomena under investigation, it is
considered desirable either to confirm an inductive result by independent
deductive reasoning from the nature of the case in the light of previous
knowledge, or to confirm a deductive conclusion by independent inductive
investigation.
An example of each of these types may help to make them clear. (1) When
Galileo was investigating the law of the velocity of falling bodies he
eventually formed the hypothesis that a body starting from rest falls with
a uniform acceleration, and that its velocity varies with the time of its
fall. But he could not devise any method for the direct verification of
this hypothesis. By mathematical deduction, however, he arrived at the
conclusion that a body falling according to his hypothetical law would fall
through a distance proportionate to the time of its fall. This consequence
could be tested by comparing the distances and the time of falling bodies,
which thus served as an indirect verification of his hypothesis. (2) By
inductions from numerous astronomical observations made by Tycho Brahe and
himself, Kepler discovered the three familiar laws called by his name,
namely, (a) that the planets move in elliptic orbits which have the sun for
one of their foci; (6) that the velocity of a planet is such that the
radius vector (i.e., an imaginary line joining the moving planet to the
sun) sweeps out equal areas in equal periods of time; and (c) that the
squares of the periodic times of any two planets (that is, the times which
they take to complete their revolutions round the sun) are proportional to
the cubes of their mean distances from the sun. These three laws appeared
to be quite independent of each other. But Newton systematised them all in
the more comprehensive induction, or theory, of celestial gravitation. He
showed that they could all be deduced from the one law that the planets
tend to move towards each other with a force varying directly with the
product of their masses, and inversely with the square of the distances
between them. (3) H. Spencer, by comparing a number of predominantly
industrial States and also, of predominantly military States, ancient and
modern, inferred inductively that the former type of State is democratic
and gives rise to free institutions, whereas the latter type is
undemocratic and tends to oppression. As the sparse evidence hardly
permitted of a rigorous application of any of .the inductive methods,
Spencer tried to confirm his conclusion by deductive reasoning from the
nature of the case in the light of what is known about the human mind. He
pointed out that in a type of society, which is predominantly industrial,
the trading relations between individuals are the predominant relations,
and these train them to humour and consider others. The result is a
democratic attitude in all. In a State, which is predominantly military,
the relations which are most common among its members are those of
authority, on the one part, and of subordination on the other. The result
is the reverse of a democratic atmosphere.
RELATION OF EPISTEMOLOGY TO OTHER BRANCHES OF PHILOSOPHY
In conclusion, I would like to discuss the relation of epistemology to
other branches of philosophy. Philosophy viewed in the broadest possible
terms divides into many branches: metaphysics, ethics, aesthetics, logic,
philosophy of language, philosophy of mind, philosophy of science, and a
gamut of others. Each of these disciplines has its special subject matter:
for metaphysics it is the ultimate nature of the world; for ethics, the
nature of the good life and how people ideally ought to comport themselves
in their relations with others; and for philosophy of science, the
methodology and results of scientific activity. Each of these disciplines
attempts to arrive at a systematic understanding of the issues that arise
in its particular domain. The word systematic is important in this
connection, referring, as explained earlier, to the construction of sets of
principles or theories that are broad-ranging, consistent, and rationally
defensible. In effect, such theories can be regarded as sets of complex
claims about the various matters that are under consideration.
Epistemology stands in a close and special relationship to each of these
disciplines. Though the various divisions of philosophy differ in their
subject matter and often in the approaches taken by philosophers to their
characteristic questions, they have one feature in common: the desire to
arrive at the truth about that with which they are concerned--say, about
the fundamental ingredients of the world or about the nature of the good
life for man. If no such claims were asserted, there would be no need for
epistemology. But, once theses have been advanced, positions staked out,
and theories proposed, the characteristic questions of epistemology
inexorably follow. How can one know that any such claim is true? What is
the evidence in favour of (or against) it? Can the claim be proven?
Virtually all of the branches of philosophy thus give rise to
epistemological ponderings.
These ponderings may be described as first-order queries. They in turn
inevitably generate others that are, as it were, second-order queries, and
which are equally or more troubling. What is it to know something? What
counts as evidence for or against a particular theory? What is meant by a
proof? Or even, as the Greek Sceptics asked, is human knowledge possible at
all, or is human access to the world such that no knowledge and no
certitude about it is possible? The answers to these second-order questions
also require the construction of theories, and in this respect epistemology
is no different from the other branches of philosophy. One can thus define
or characterise epistemology as that branch of philosophy, which is
dedicated to the resolution of such first- and second-order queries.
BIBLIOGRAPHY:
1. A preface to the logic of science, by Peter Alexander, Sheed and Ward,
London and New York, 1963.
2. Popper selections, edited by Dawid Miller, Princeton University press,
1985.
3. The critical approach to science and philosophy, edited by Mario Bunge,
The free press of Glencoe Collier- Magmillan limited, London, 1964.
4. Britannica encyclopaedia, 1948.
5. Logic without metaphysics, by Ernest Nagel, Glencoe, Ill..: Free Press,
1957.
6. "Epistemology, History of,", by D.W. Hamlyn. The Encyclopaedia of
Philosophy.
7. Introduction to Objectivist Epistemology, expanded 2nd ed., by Ayn Rand,
New York: Penguin Group, 1990.
