That formulation is only seeking to deal with the logic of the economic rationality assumption. Behind that, as Hay is of course fully aware, lie probems about the notion that self interested behaviour and rational behaviour can be equated. Other theorists, although starting out from an economistic mode of reasoning, recognise that other behavioural modes may determine action. Le Grand, for example, makes a distinction in the analysis of public officials between 'knaves', motivated by self-interest, and the more public spirited altruists, whom h similarly seek to apply evidence from psychology to economic analyses of motivation (2003). Yet even with these modifications, surely Hay's strictures about determinism a What is merely being pointed out is that what is determined may vary.