The theory of population having both scientific and political dimensions based on the writings of Thomas Robert Malthus that views a check on the rate of population growth as both desirable and essential. These checks are either positive including famine, war, and disease or preventive involving moral restraint: late marriage, premarital abstinence, and celibacy. Malthusianism is generally associated with the operation of positive checks on population growth and, if as is likely, these fail to achieve a balance, the inevitability of disastrous shortages.