John Broome has argued that alleged cases of value incomparability are really examples of vagueness in the betterness relation. The main premiss of his argument is ‘the collapsing principle’. I argue that this principle is dubious, and that Broome's argument is therefore unconvincing. Correspondence:c1 [email protected].

This paper argues for the existence of a fourth positive generic value relation that can hold between two items beyond ‘better than’, ‘worse than’, and ‘equally good’: namely ‘on a par’.

This paper begins with a response to Josh Gert’s challenge that ‘on a par with’ is not a sui generis fourth value relation beyond ‘better than’, ‘worse than’, and ‘equally good’. It then explores two further questions: can parity be modeled by an interval representation of value? And what should one rationally do when faced with items on a par? I argue that an interval representation of value is incompatible with the possibility that items are on a par (a mathematical (...) proof is given in the appendix). I also suggest that there are three senses of ‘rationally permissible’ which, once distinguished, show that parity does distinctive practical work that cannot be done by the usual trichotomy of relations or by incomparability. In this way, we have an additional argument for parity from the workings of practical reason. (shrink)

James Griffin (1986, 1997, 2000) and Ruth Chang (1997) have argued that alternatives (and values) can be comparable when it is neither true that one is better than the other, nor true that they are exactly equal in value. The relation which holds between them has gone under various names: the alternatives are (Griffin) or (Chang). In this paper, I give a formal analysis of this relation. This analysis allows us to distinguish between two slightly different notions of . It (...) is argued that the distinction between these notions is important for discussions of rationality, as is the distinction between or and incomparability. (shrink)