  Both Martha Nussbaum (1986) and David Wiggins (1980) have argued for pluralism on the grounds that only pluralism can explain akrasia, or weakness of will. An agent is said to suffer from weakness of will when she knowingly chooses a less good option over a better one. On the face of it, this is a puzzling thing to do—why would someone knowingly do what they know to be worse? A pluralist has a plausible answer—when the choice is between two different sorts of value, the agent is preferring A to B, rather than preferring less of A to more of A. Wiggins explains the akratic choice by suggesting that the agent is ‘charmed’ by some aspect of the choice, and is swayed by that to choose what she knows to be worse overall (Wiggins 1980, p. 257). However, even Michael Stocker, the arch pluralist, does not accept that this argument works. As Stocker points out, Wiggins is using a distinction between a cognitive and an affective element to the choice, and this distinction can explain akrasia on a monist account of value too. Imagine that a monist hedonist agent is faced with a choice between something that will give her more pleasure and something that will give her less pleasure. The cognitive aspect to the choice is clear—the agent knows that one option is more pleasurable than the other, and hence on her theory better. However, to say that the agent believes that more pleasure is better is not to say that she will always be attracted to the option that is most pleasurable. She may, on occasion, be attracted to the option that is more unusual or interesting. Hence she may act akratically because she was charmed by some aspect of the less good choice—and as Stocker says, there is no need to posit plural values to make sense of this—being charmed is not the same as valuing. (Stocker 1990, p.219).