Knowledge is reciprocal disscus?

Ab-so-lutely not! For knowledge to be reciprocal, it needs to have a common basis both in reality (less there would be no knowledge at all) and in belief (less there be no common knowledge). Even granting the former, which I do not hold, the latter is impossible for me to allow.

Knowledge as justified true belief:
Belief - "I hold there is a building there"
Justified - "I have many of the phenomenological sensations of buildingness when I look/go over there"
True - 'There really is a building over there'

I fault common knowledge at the 'belief' stage (but I also doubt it, and the whole shabang, at the 'true' stage) - that is, when I hold there is a building over there, I either hold its buildingness as the total of the phenomenology of what I sense, the concept of buildingness I have in my head, or some combination of both (and its likely the latter). In all three cases, these are nonreciprocal concepts; there is no sharing of phenomenological sensations nor mental concepts almost by definition. So if the beliefs are never the same, the knowledge is never the same. QED, if very very briefly.