Any wide-ranging system of beliefs, ways of thought, and categories that provide the foundation of programmes of political and social action: an ideology is a conceptual scheme with a practical application.

Derogatorily, another person’s ideology may be thought of as spectacles that distort and disguise the real status quo (see false consciousness). Promises that political philosophy and morality can be freed from ideology are apt to be vain, since allegedly cleansed and pure programmes depend, for instance, upon particular views of human nature, what counts as human flourishing, and the conditions under which it is found.