Full Idea
Foundationalist epistemology takes all empirical knowledge to be grounded in the introspective knowledge each mind has of its own states, …holding that introspective judgements are 'incorrigible' or 'infallible', and mental states are 'self-intimating'.
Clarification
'Self-intimating' means obvious; 'incorrigible' means can't be proved false; 'infallible' means must be true
Gist of Idea
Empirical foundationalism says basic knowledge is self-intimating, and incorrigible or infallible
Source
Sydney Shoemaker (Introspection [1994], p.396)
Book Reference
'A Companion to the Philosophy of Mind', ed/tr. Guttenplan,Samuel [Blackwell 1995], p.396
A Reaction
Descartes' foundationalist Cogito also seems to be based on introspection, making introspection the essence of all foundationalism. The standard modern view is that introspective states are incorrigible, but not infallible.