The coherence theory of truth (which Russell rejects) claims, roughtly, that a belief is true if it coheres with "the completely rounded system which is The Truth." (P 192a)

Two Problems with the Coherence Theory

1. There may be more than one coherent body of beliefs. (P 192a)
2. "the laws of logic supply the . . . framework within which the test of coherence applies, and they themselves cannot be established by this test." (P 192b)

What Role Coherence Plays

Coherence "is often a most important test of truth after a certain amount of truth has become known." (P192b)