Ideology has an ambiguous status in the academic study of British politics. Often it is regarded as a sub-category of political theory rather than having any place within political science. Ideological conflict was a key element in British politics in the 1970s and 1980s when the major parties were sharply divided. After the downfall of Margaret Thatcher in 1990 – and especially when the Labour Party was led by Tony Blair after 1994 – some commentators spoke of a new ideological ‘consensus’ in which parties were more concerned with the pursuit of office than principled objectives. Ideologies are best understood as belief systems which help people to make sense of the world. The best way of explaining the nature of political ideology in Britain is to provide a brief survey of modern British politics from the point of view of ideas. The Irish-born politician Edmund Burke (1729–97) is usually credited as the intellectual founder of conservative ideology.