![](bg9.png)
system proposed in (Modica and Rustichini, 1994) is
the early work of the approach. (Halpern, 2001) found
it to be equivalent to a part of the logic in (Fagin and
Halpern, 1988). Since the work of (Modica and Rus-
tichini, 1999), the focus has been on a formalization
of the concept of unawareness (Heifetz et al., 2006;
Heifetz et al., 2008).
7 CONCLUSION
In this paper, we have introduced Awareness Logic
with Partition (ALP ), where we incorporated the no-
tion of partition among possible worlds and have ex-
tended the distinction of aware/unaware propositions
to indistinguishable possible worlds. With this, we
have properly reflected the agent’s awareness to other
agents’ knowledge. Employing this framework, we
have shown an example where the behavior of each
agent could be logically explained.
Our contributions of this logic are two-fold. From
the logical viewpoint, we introduced the syntax and
the semantics of ALP and have shown its complete-
ness. From the viewpoint of applicability to real
world, we have shown the architecture to explain the
strategic behavior of rational agents in a society or
game theory. We expect that the logic offers a founda-
tion for formal expressions of human minds and prac-
tical agent communication.
There are several directions in the future. On the
conceptual side, we consider incorporating more epis-
temic actions and concepts, such as common knowl-
edge, to represent practical agent communication. On
the technical side, the axiomatic system of the dy-
namic extension, discussed in Section 5, remains. In
addition, our logic is applicable to the studies deal-
ing with multiple agents’ reasoning, such as descrip-
tion and analysis of games that take into account play-
ers’ awareness of possible strategies (Feinberg, 2005;
Kaneko and Suzuki, 2002). Specifically, we plan to
use the logic to analyze rationality to reach an equi-
librium in games with awareness.
ACKNOWLEDGMENTS
The authors thank Professor Thomas
˚
Agotnes and
the anonymous reviewers for their many insightful
comments. This work was supported by JSPS kaken
22H00597.
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