   Many utilitarians are monists, arguing that there is only one fundamental value and that is well-being or pleasure or happiness, or something of that sort. In other words, some utilitarians are committed to hedonism.  Monist utilitarians must claim that all other putative values, such as friendship, knowledge and so on, are only instrumental values, which are valuable in so far as they contribute to the foundational value. But utilitarians need not be monists. Amartya Sen, for example, argues that utilitarians can take a ‘vector view of utility’, according to which there are differences in the qualities as well of the quantites of utility in goods in the world. According to Sen, we should interpet Mill as a pluralist in this way. (I return to Mill below: it is not entirely clear how we should understand his view). Sen points out that desire satisfaction theorists can be pluralists too. Just as different sorts of pleasure might have different sorts of value, so different desires might have different sorts of value. (Sen, 1981). Even utilitarians who claim that the value to be maximized is well-being can be pluralist: a prominent view of well-being is that well-being itself is plural, an objective list of things that are fundamentally plural. (See Finnis 1980; Griffin 1986; for recent defences see Fletcher, 2013, Lin, 2014). Another reason to think that hedonistic utilitarians should be pluralists is that it seems essential to say something about the disvalue of pain. As Shelly Kagan points out (2014), we need an account of ill-being in addition to an account of well-being. 