 Determinables as ontologically or causally redundant. Irreducible determinables have been taken to be ontologically and causally redundant, since determinates which we have independent reason to posit can explain or do anything that determinables purportedly explain or do. Hence Massin (2013) maintains against Johansson (2000) that perceived inexact resemblances between determinates can explain the “seen unity of the determinate colors”, and Gillett and Rives maintain that determinables are causally unnecessary: