Open University course units are presented on the philosophy of equality and inequality (Unit 3) and on personal inequality as an ideological concept (Unit 4). The substance of Unit 3 consists of extracts from the writings of eight philosophers. The role of the philosopher in forming legitimatizing ideologies is also illustrated. The eight philosophers are: H. Ireton, J.-J. Rousseau, A. de Tocqueville, J. S. Mill, K. Marx, J. F. Stephen, F. Nietzsche, and R. H. Tawney. The aims of Unit 4 are to examine: (1) the concept of personal inequality and its value in interpreting social patterns of inequality, and (2) the concept of innate or natural endowment. The first major section traces the origins of the concept of innate intelligence by examining Darwin's theory of evolution, evaluates its implication for views on the nature of society, and traces the Eugenics movement from its origins in the work of Galton. The scientific and political reactions to doctrinaire forms of biological determinism, the relationship between scientific and ideological thought, and reasons for the continued use of a concept of inherited intelligence are discussed. The development of the intelligence testing movement and further implications are also considered. Questions are presented at the beginning of each unit, and outline answers are given at the end of the unit. References and bibliographic citations are also included. (SW)