Kingsley Davis occupies an unusual double position in sociology: he wrote its most contested defence of inequality and helped found its most technically demanding subfield. The 1945 paper written with Wilbert E. Moore made differential rewards the functional answer to the problem of staffing a society's positions, and provoked a critical literature that has never quite closed. In demography he gave the demographic transition its name in the same year, and went on to supply population studies with much of its conceptual furniture.

The two enterprises share a method. In both, Davis begins from a functional requirement any society must meet — filling its positions, reproducing its members — and asks what arrangements meet it and at what cost. This is functionalism used as an analytic device rather than a philosophy, which is why his demographic work has aged better than his stratification theory.

Life and intellectual formation

Davis took his doctorate at Harvard, where the department was being built by Pitirim Sorokin and where Talcott Parsons was formulating the theory of action; Wilbert Moore was a fellow student. He taught at Princeton and Columbia before long tenures at Berkeley and later the University of Southern California, directing major population research programmes and serving as president of the American Sociological Association. His treatise Human Society (1949) is a systematic functionalist sociology that treats population as a sociological rather than a merely statistical fact, and his earlier papers on prostitution and on the child in the social structure show the same instinct: take a phenomenon usually handled morally and ask what it does within a system of relations.

The functional theory of stratification

The Davis and Moore argument begins with a problem of allocation. Every society must place its members in the positions its division of labour requires and motivate them both to seek those positions and to perform the duties attached to them. Positions, however, are unequal in two respects: they differ in functional importance to the society, and they differ in the scarcity of qualified personnel, since some require long, costly and uncongenial training or unusual talent.

It follows that a society must attach unequal rewards to positions. The rewards fall into three kinds: those sustaining subsistence and comfort, those providing humour and diversion, and those serving self-respect and ego expansion. Institutionalised inequality of reward is therefore an unconsciously evolved device by which societies ensure that their most important positions are conscientiously filled. Stratification, on this reading, is universal and functionally necessary, and its shape varies with what a society values — priesthood ranks high where religion is central, technical expertise where production is.

The Tumin critique

Melvin Tumin's 1953 reply is as much a part of the syllabus as the original.

  • Functional importance cannot be measured independently of reward, so the argument is circular: importance is inferred from the rewards a position already receives.
  • Interdependence undercuts the ranking. Unskilled labour is as indispensable to output as management; the claim of greater importance smuggles in a value judgement.
  • Talent is not scarce in the way assumed. Stratification restricts the discovery and training of talent, since the children of the poor never reach the starting line — inequality shrinks the pool it claims to select from.
  • Training is not a sacrifice but deferred income, usually underwritten by the family and carrying prestige of its own; lifetime returns far exceed any loss.
  • Alternative motivations exist — vocation, intrinsic satisfaction, social duty — so material inequality is one solution, not the only one.
  • Stratification is dysfunctional. It breeds hostility and distrust, unequally distributes favourable self-images, weakens the loyalty of the deprived, and legitimises the reproduction of privilege.

Marxist critics added that the theory takes existing reward structures as evidence of their own necessity, converting an ideology of the advantaged into a scientific proposition. Comparative evidence is also awkward for it: rewards track power and inheritance at least as closely as they track function.

Demographic transition and population growth

Davis's 1945 paper set out the sequence now taught as demographic transition theory: societies move from a regime of high birth and high death rates, through a phase in which mortality falls while fertility remains high and population therefore grows explosively, to a regime of low birth and low death rates. The critical insight is that the two do not move together — mortality responds quickly to public health, nutrition and order, whereas fertility is embedded in family structure, inheritance, religion and the status of women, and changes slowly.

He is generally credited with putting the phrases population explosion and zero population growth into circulation, and he used them polemically. His 1967 argument in Science held that family-planning programmes were unlikely to stabilise population on their own, because they helped couples reach the family size they already wanted rather than changing what they wanted; stabilisation required change in the structures that make large families rational, particularly in the position of women, in education and in employment.

Against a mechanical reading of transition theory he proposed a theory of change and response: faced with sustained natural increase, families respond on many fronts at once — postponed marriage, contraception, abortion, migration, sending members into wage work — a multiphasic response whose mix depends on the society's structure.

Intermediate variables and the study of fertility

The most technically durable contribution is the framework published with Judith Blake in 1956. Social structure and culture, they reasoned, cannot affect fertility directly; they must operate through a limited set of intermediate variables — the biological and behavioural channels through which any determinant must pass. These fall into three groups: variables governing exposure to intercourse, such as age at entry into unions, permanent celibacy and time spent outside unions; variables governing exposure to conception, such as contraception and sterility; and variables governing gestation and successful parturition, chiefly foetal mortality from voluntary and involuntary causes.

The framework's power lies in its discipline. Any claim that caste, religion, literacy or urbanisation influences fertility must specify which intermediate variable carries the effect — which is why it became the base for later work on the proximate determinants of fertility and remains the best way to organise an answer on the social determinants of fertility in India.

Urbanisation and over-urbanisation

Davis compiled some of the first systematic global series on urban growth, distinguishing urbanisation — a rising proportion of people living in towns, a process that must eventually stop — from the mere growth of cities, which can continue indefinitely. His 1951 study of India and Pakistan remains a landmark reconstruction of subcontinental population history from census material.

From this came the idea of over-urbanisation: in many developing countries the urban share of population is high relative to the level of industrialisation and agricultural productivity, so cities absorb people whom industry cannot employ. The result is a swollen informal sector, slum settlement and rural poverty transferred to the city rather than resolved by it — a diagnosis that shaped Indian debates on migration and city growth, though later scholars doubted that any single ratio of urbanisation to industrialisation can be called normal.

Criticisms and legacy

Beyond Tumin, Davis is criticised for the conservative bent of functional reasoning, which turns description of what a society does into justification of it. Demographers fault transition theory for generalising a western European sequence and for uneven fit with the evidence, since fertility fell in parts of France before industrialisation and stayed high in some industrialised settings. His alarm about numbers has been read as neo-Malthusian, diverting attention from distribution and reproductive rights, a charge sharpened by feminist scholarship that treats population policy as a matter of women's autonomy.

Yet the Davis and Moore thesis survives as the functionalist position against which every other theory of stratification is defined, and the Davis–Tumin exchange remains the discipline's clearest worked example of theoretical argument. In demography his influence is structural rather than citational: the vocabulary of transition and the discipline of intermediate variables are now simply how the subject is done.

For the UPSC answer

Davis pays twice, so know which Davis a question wants. On stratification, present Davis and Moore as a two-step argument — differential functional importance plus scarcity of trained talent, therefore differential reward — and then deploy Tumin point by point, since examiners reward the enumerated critique far more than a general complaint about conservatism. On population, use him for demographic transition and the Davis–Blake intermediate variables, and show reach by adding change and response, which pre-empts the charge that transition theory is mechanical. Over-urbanisation is the concept for Paper II questions on Indian urbanisation, paired with the point that urban growth has outpaced industrial employment. A strong answer links the two halves: both treat inequality and reproduction as things societies organise rather than things that simply happen.

References & further reading

  1. Davis, K. (1945). The World Demographic Transition. Annals of the American Academy of Political and Social Science, 237, 1–11.
  2. Davis, K. and Moore, W. E. (1945). Some Principles of Stratification. American Sociological Review, 10(2), 242–249.
  3. Davis, K. (1949). Human Society. New York: Macmillan.
  4. Davis, K. (1951). The Population of India and Pakistan. Princeton: Princeton University Press.
  5. Davis, K. and Blake, J. (1956). Social Structure and Fertility: An Analytic Framework. Economic Development and Cultural Change, 4(3), 211–235.
  6. Tumin, M. M. (1953). Some Principles of Stratification: A Critical Analysis. American Sociological Review, 18(4), 387–394.