Keynes famously claimed 'soon or late, it is ideas, not vested interested which are dangerous for good or evil'. His neoliberal critics have frequently concurred with this contention, and have happily used the example of Keynes to illustrate it. But is 'the power of ideas' consistent with neoliberal doctrine? The paper argues that the most conclusive case for categorical 'market success' propositions will eliminate ideas as explanatory of economic failure , and imply such failures must be traced to exploitation of by special interests . However, the paper argues that neoliberalism is committed to 'government failure' not 'market success', and government failure does give room for ideas to have power, for good or ill.