 One may treat “\(KA\)” in (H) as not really standing for knowledge or belief. We should read it as “\(A\) follows logically from the agent’s knowledge”, or “The agent is committed to \(A\), given what it knows/believes”. Then we still lack some logical account of knowledge and belief per se, as opposed to some derivative attitude or conditional commitment. The commitment itself may be questioned: are we committed to believing everything, given that we have inconsistent beliefs? In what sense must a finite agent believe infinitely many logical consequences? Such a “must” lacks a corresponding “can”.