Full Idea
Coherence theories of truth differ on their accounts of the coherence relation, and on their accounts of the set (or sets) of propositions with which true propositions occur (the 'specified set').
Gist of Idea
Coherence theories differ over the coherence relation, and over the set of proposition with which to cohere
Source
James O. Young (The Coherence Theory of Truth [2013], §1)
Book Reference
'Stanford Online Encyclopaedia of Philosophy', ed/tr. Stanford University [plato.stanford.edu], p.1
A Reaction
Coherence is clearly more than consistency or mutual entailment, and I like to invoke explanation. The set has to be large, or the theory is absurd (as two absurdities can 'cohere'). So very large, or very very large, or maximally large?
Related Idea
Idea 19078 Coherence with actual beliefs, or our best beliefs, or ultimate ideal beliefs? [Young,JO]