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In the social sciences there are many propositions
that are called 'laws', such as, for example, the law
of increasing specialization (sociology), the iron
law of oligarchy (political science), the laws of
motion of capitalism (Marxian economics),
Pareto's law of income distribution (economics),
the law of diminishing returns (economics), etc.
When we examine such statements we discover
that, while they all represent generalizations, they
involve very different kinds of generalizations.
1. Empirical laws
• In his System of Logic (Book VI, chapter V)
John Stuart Mill defines an ‘empirical law’
as ‘an uniformity, whether of succession or
of coexistence, which holds true of all
instances within our limits of observation,
but is not of a nature to afford any assurance
that it would hold beyond those limits…’.
• Let us look at two of the laws in the list
above that are clearly empirical in nature:
‘Pareto’s law of income distribution’ and
'the iron law of oligarchy’ enunciated by
Robert Michels. Vilfredo Pareto, Italian
engineer-economist-sociologist, put forward
the striking law of income distributions in
his lectures at the University of Lausanne,
published as Cours d’economie politique
(Course in Political Economy, 1896-7).
He examined the data on incomes in all
countries for which statistics were then
available and became convinced that the
pattern of income distribution was
substantially the same in all countries and
could be represented by the formula :
log N = log A –α log X
• where N is the number of people whose
income exceeds X, and A and α are
constants. If we plot the (cumulative)
income distribution on double-log graph
paper it will be a straight line with slope
equal to α. The coefficient of α is a
measurement of the degree of inequality in
the income distribution.
Pareto’s empirical studies showed not only
that the above formula fitted the data well
but that, when calculated, α turned out to
have substantially the same magnitude in all
countries, indicating that the degree of
inequality in the distribution of income was
uniform. This suggests that α in Pareto's
formula is similar to Newton’s coefficient of
gravitational attraction: a ‘natural constant’.
2. Analytical laws
This term refers to the kinds of laws one
finds in the disciplines of logic and
mathematics. For example, the ‘law of
contradiction’ states that:
– A thing cannot be both X and not-X
and the ‘law of the excluded middle’ states
– Everything must be classifiable as an X or a
The ‘law of transitivity’ states that
quantitative relationships are such that:
– If A is greater than B and B is greater than C,
then A is greater than C.
A concrete example of the first two of these
laws would be the statement:
– A thing is either a swan or it is not; it can't be
both and of the transitivity law:
– If Albert is taller than Bertha, and Bertha is taller
than Clarence, then Albert is taller than Clarence.
• It is important to note that examples of this
sort merely illustrate the relevant analytic
laws; they play no role in proving them.
Analytic laws are laws of reason or laws of
rational thought, not laws of nature in any
• When we state the transitivity law we are
not asserting anything empirical, such as,
for example, that people behave as if they
believe that when A > B and B > C, then A
> C; we are saying that any other behaviour
would be irrational.
• We are not required to assert that people do
always behave rationally; that would be an
empirical statement, not an analytic one.
3. Causal laws
What most people would find unsatisfactory
about empirical laws and analytic laws is
that they do not connect events together in a
causal fashion. If a ‘law’ is expected to
furnish an explanation of why the
phenomena are as they are and not
otherwise, then empirical laws and analytic
laws are not laws at all.
Many philosophers, and most scientists,
emphasize the importance of causal laws in
science but, unfortunately, there is little
agreement as to what is meant by concept of
‘cause’. In this section I want to focus on a
‘model’ of causation which, though
unsatisfactory in some ways, helps one to
understand how the concept of cause is
typically used in common speech, and by
scientists in their professional work.
Let us consider what is involved in making
a statement like ‘The forest fire was caused
by lightning’. Obviously lightning (L) was
not sufficient to cause the fire (F), since the
forest had to be dry (D) for it to have had
the effect it did. But (L) was not necessary
either, since, given D, F could have resulted
from, say, a discarded cigarette (C).
This is vitally important to the
understanding of ‘laws’ of social behaviour.
For example, the ‘law of demand’ in
economics says: ‘Other things held constant,
when the price of a commodity goes up,
people buy less of it.’ It is not necessary that
everyone buy less, however; the law merely
says that the aggregate purchase will be less.
If we were to jot down every time we
encounter a nomological proposition in our
reading and then looked over the list when
we had, say, twenty items, we would be
struck by differences in the level of
organization that is represented by them.
Suppose you are a student of biology.
You read, for example, about
(1) the constancy of the 'Chargaff ratios' in the
nucleotides that are part of the DNA molecule
inside the cell;
the principles that govern cell division in mitosis;
the mechanism of cell differentiation in
the processes of reproduction;
the ecological interaction among the species of
plants and animals in an area.
These represent very different levels of
is at the chemical level;
is at the level of the cell;
Is concerned with tissues and organs;
deals with the functions of a whole organism;
focuses upon a community composed of different
species of organisms.
When scientists try to establish the 'laws of nature'
they are dealing with a reality that is law-governed
but one in which different laws operate at different
levels of organization.
The Chargaff ratios and the principles of predatorprey equilibrium are both biological laws, but the
ecologist has very little interest the former and the
latter is not of much relevance to the work of a
So it serves no purpose to refer in general to 'the
laws of biology*.A list of such laws would be so
exceedingly heterogeneous that it would have little
Biologists stick to specialities such as molecular
genetics, cell physiology, embryology, and so on,
because the laws that relate to such restricted
domains of phenomena form a coherent set, and
one can see how new research-fits into the body of
already established knowledge in the restricted
domain of interest.
The methodology of analogical argument is too
complex a subject to be examined here but it is
worth noting that analogical reasoning is as
dangerous as it is tempting. A common fallacy in
reasoning is called by philosophers ignoratio
This refers to the fallacy of setting out to prove
one proposition, proceeding to prove a different
one, and then claiming that the original objective
has been achieved.
A metaphor or analogy can effectively
illustrate an argument for didactic purposes
but it cannot serve as a valid demonstration
unless the analogy is very close.
C. SOCIAL AND NATURAL
The comparison of the social and the natural
sciences will occupy our attention
frequently in the following pages, as it has
At this point it may be useful to draw upon
what has been discussed in sections A and B
of this chapter to make some remarks on the
differences between the social and natural
In previous sections and chapters their
similarities have been stressed; but a
recognition of their differences is also
important. Six major points of difference
should be noted.
1. Nomological propositions are possible only
with respect to phenomena that have some
reasonable degree of uniformity.
2. The social sciences are able to make very little
use of controlled experiments.
3. Perhaps because of the limited ability to
experiment, research in social science cannot be
conducted on the basis of pure curiosity to the
degree that is possible in the natural sciences.
4. Closely connected with the practical or applied
aspects of the social sciences is the fact that they
are more involved with value judgements than the
5. The social sciences deal with the behaviour of
humans, and many (but by no means all) social
scientists would claim that this makes them
fundamentally different from the natural sciences.
6. Finally, we should note once again that wholepart relationships in social phenomena are not like
those of the natural world.
D. POSITIVE AND
The terms “positive” and “normative” are
frequently used in the literature of social
science to differentiate between
propositions about empirical facts and
propositions that are value judgements.
Distinguishing between these two types of
propositions is essential if one is to think or
speak clearly on any matter, but especially
so in dealing with social questions.
The origin of the term “normative” is even more
peculiar. It derives from the Latin word norma,
which is the name for a carpenter's tool, a square
for setting right-angles.
From this clearly “positive” activity, the term
came to be used to mean a standard of good
conduct, or “norm”, perhaps derived from the
notion that a carpenter conducts himself properly
when he gets his angles truly ninety degrees when
they should be.
By the mysterious processes of language
evolution “normative” is now used in
English to refer to those aspects of social
science where value judgements enter the
The essential difference between positive
and normative propositions can be put this
way: when a positive proposition fails to be
supported by empirical evidence, the
proposition is called into question; but when
a normative proposition is at odds with the
state of the world, the state of the world is
called into question.
Put somewhat differently, when a person's
positive beliefs do not agree with the facts,
he is rationally obliged to change his beliefs;
but when the facts do not agree with a
person's normative beliefs he is morally
obliged to change the facts if he can.
The member of the Flat Earth Society
should change his geographical theory; the
thief should change his conduct. Positive
and normative propositions are both vital to
social science in its efforts to understand
and to deal with social problems, but it is
essential to clear thinking that they should
not be confused.