[New Entry by Bart Geurts on October 3, 2024.]
Compare and contrast the following scenarios. In the first, Betty sends Fred an email saying that she will be in town tomorrow, and then sends the same message to Barney. In the second scenario, Betty addresses the two men jointly with one message. In both scenarios, Barney and Fred are apprised of the fact that Betty will be in town tomorrow, but otherwise their information states are palpably different: whereas in the first scenario they unwittingly share the same information, in the second scenario, it is common ground between…

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