 \((\rPub(q),e)\) has the following intuitive effect: the public announcement of q (i.e., event e) occurs and this is common knowledge; however, the agents still maintain the possibility that the negation \(\lnot q\) was announced (i.e., event f occurred). In effect, the agents will come to believe q (because the announcement of this was most plausible), but they will nevertheless maintain the less plausible possibility that q is false. This allows the agents to accept the announced formula q but with some caution: they can still revise their beliefs if they later learn that q is false. 