Full Idea
When the whole range of empirical beliefs is taken into account, all of them more or less dependent on memorial knowledge, we find that those which are most credible can be assured by their mutual support, or 'congruence'.
Gist of Idea
We rely on memory for empirical beliefs because they mutually support one another
Source
C.I. Lewis (An Analysis of Knowledge and Valuation [1946], 334), quoted by Erik J. Olsson - Against Coherence 3.1
Book Reference
Olsson,Erik J.: 'Against Coherence' [OUP 2008], p.35
A Reaction
Lewis may be over-confident about this, and is duly attacked by Olson, but it seems to me roughly correct. How do you assess whether some unusual element in your memory was a dream or a real experience?