If this is nothing more than a stipulation about how we ought to use the term ‘ideological', then perhaps it will do no harm. But if it is a proposal about how historians ought to set about the business of explaining beliefs, then it seems to me fatal for just the reasons I have sought to give. It refuses to recognise that one of the reasons why someone may hold a certain belief is that there is good evidence in favour of it, that it fits well with their other beliefs, and so on – in a word, that it is rational for them to hold it. If we refuse to speak in these terms, we deprive ourselves of an indispensable means of identifying the most appropriate lines of enquiry to follow in any given case.