Szuman, Alicja2013-03-182013-03-181998Ruch Prawniczy, Ekonomiczny i Socjologiczny 60, 1998, z. 3-4, s. 351-3600035-9629http://hdl.handle.net/10593/5488Some characteristic concepts attempting to explain a mechanism of demographic transformations were presented in the article. All of them have exponed the phemomenon of periodicity as a determinant of population development. Changes in numeral level of population have been explained with wars or pests (G. Bouthoul, W. Able, E. Rosset, A. Lòsch), detections were also made to find out in demography pre-causes of some social phenomenons (J. C. Russel), and some other conceptions are grown on the groundwork of biological ideas (C. Gini, R. Pearl). The attempts made up to the present to find out some regularity of population increase depending on successive phases of development of this process have all failed. Theories were built on a basis of concrete sources of materials which were incomplete as a rule and, above all, incomparable and, as such, it led to distorted results. Fluctuations within the process of population reproduction had therefore various forms. No one from the theories appealing to periodicity does explain mechanism that generates increase in the population number.plCYKLICZNOŚĆ W TEORIACH LUDNOŚCIOWYCHPERIODICITY IN POPULATIONAL THEORIESArtykuł