 stating thus that if the agent knows \(\varphi \rightarrow \psi\) and an announcement of \(\psi\) (“\([\psi{!}]\)”) makes her know it \((\psi)\), then she can perform an act of belief revision with \(\varphi\) (“\([\varphi\Uparrow]\)”) in order to believe it. This formalization emphasizes not only that the agent’s initial knowledge plays a crucial role in the generation of possible abductive solutions, but also that the chosen solution can only be accepted in a weak way, therefore making it a candidate for being discarded in the light of further information.