 ‘Equality’ is a contested concept: “People who praise it or disparage it disagree about what they are praising or disparaging” (Dworkin 2000, p. 2). Our first task is therefore to provide a clear definition of equality in the face of widespread misconceptions about its meaning as a political idea. The terms ‘equality’ (Greek: isotes; Latin: aequitas, aequalitas; French: égalité; German Gleichheit), ‘equal’, and ‘equally’ signify a qualitative relationship. ‘Equality’ (or ‘equal’) signifies correspondence between a group of different objects, persons, processes or circumstances that have the same qualities in at least one respect, but not all respects, i.e., regarding one specific feature, with differences in other features. ‘Equality’ must then be distinguished from ‘identity’, which refers to one and the same object corresponding to itself in all its features. For the same reason, it needs to be distinguished from ‘similarity’ – the concept of merely approximate correspondence (Dann 1975, p. 997; Menne 1962, p. 44 ff.; Westen 1990, pp. 39, 120). Thus, to say that men are equal, for example, is not to say that they are identical. Equality implies similarity rather than ‘sameness’.