  This objection requires the chance of an event to be insensitive to reference class. Recently, Hájek (2007) has argued that no adequate conception of probability is immune to a reference class problem, so that this requirement cannot be met. (For a related view of relativised chance, though motivated by quite different considerations, see Glynn 2010.) However, as Hájek notes, this conclusion makes it difficult to see how chance could guide credence, and it remains an open question whether a relativised theory of chance that meets the platitudes concerning chance can be developed.