A critique of a system, in order to be meaningful and important for one who adheres to the system, must be in accordance with the elements of the system in question, ie. it must be shown that the system in question is self-referentially incoherent, rather than being different or in contradiction to the system we ourselves affirm.A belief-set, may contain elements which serve to increase one's belief in the belief-set itself, eg, religious experience in regards to the religion affirmed, and obviously, competing belief-sets may have elements which serve to increase the belief in the belief-set, but this fact is hardly an objection.In order to justify my beliefs, I can only rely on the beliefs I already hold, ie. in order for me to justify all the propositions which I affirm to be true, I must use propositions which I hold to be true. This is the consistent, and necessarily circular nature of a consistent epistemology. To use an analogy, the quine axiom is a set, which is an element of itself. Or if you prefer, the premises which I use to justify my beliefs, are themselves believed, and therefore my belief-set is self-referential.
The diversity of beliefs brought about seems to tell me that this belief producing mechanism is terribly unreliable at best.