Epistemic Circularity and Easy knowledge in Epistemology of Ernest Sosa

The Epistemic Requirement Principle says:”A knowledge source K can yield knowledge for S only if S knows that K is reliable”. If we affirm KR, we face the problem of vicious circularity Because we attain the knowledge that our epistemic sources are reliable, through beliefs derived ultimately from that epistemic sources. But if we deny KR, we have another problem is known easy knowledge. This problem is that once we deny KR we come to know our faculties are reliable in ways that intuitively are too easy. There are some solutions about this problem among these sosa’s suggestion that deny KR in Animal knowledge and accept KR in Reflective knowledge. He maintains that we have virtuous circle in Reflective knowledge.