Full Idea
The Isolation Argument objects that coherence theories cut justification off from the world.
Gist of Idea
Coherence theories isolate justification from the world
Source
J Pollock / J Cruz (Contemporary theories of Knowledge (2nd) [1999], §3.2.4)
Book Reference
Pollock,J.L./Cruz,J: 'Contemporary Theories of Knowledge (2nd)' [Rowman and Littlefield 1999], p.74
A Reaction
I don't see this as a strong objection. Justification can be in the way beliefs cohere together, but the beliefs themselves consist of holding propositions to be true, and truth asserts a connection to the world (I say).