Abstract: The introduction to the book discusses the fact that the idea of equality is confronted by two different types of diversities: (1) the basic heterogeneity (diversity) of human beings, and (2) the multiplicity of variables in terms of which equality can be judged. This book is concerned with both these diversities, and also, specifically, with the relation between the two. The heterogeneity of people leads to divergences in the assessment of equality in terms of the choice of different focal variables (income, wealth, etc.), which in the language of economics, are called ‘space’. It is pointed out that ethical theories that reject equality in terms of one variable or space, may endorse it in terms of another. After a preamble on these matters, the introduction gives an outline of the content of the rest of the book.

Keywords: assessment, equality, heterogeneity, human diversity, inequality, space,