Emerging church people of a more philosophical bent often speak critically of ‘foundationalism’.

What’s that?

Nancey Murphy explains:-

Foundationalism is a theory about knowledge.  More specifically, it is a theory about how claims to know can be justified.  When we seek to justify a belief, we do so by relating it to (basing it on, deriving it from) other beliefs.  If these other beliefs are called into question, then they, too, must be justified.  Foundationalists insist that this chain of justification must stop somewhere; it must not be circular, nor must it constitute an infinite regress.  Thus, the regress must end in a ‘foundation’ of beliefs that cannot themselves be called into question.

Anglo-American Postmodernity, cited in Gibbs & Bolger, Emerging Churches: Creating Christian Community in Postmodern Cultures, 69.