Question

Question 4. Suppose that Aaron (A) sends Britney (B) an email suggesting a place to meet (M). If Britney receives the email, she sends an email to Aaron confirming that she received Aaron’s email. Further, suppose that when either Aaron or Britney sends an email, there is a small chance that the email gets lost, and the sender is not told whether their sent email was lost or not. Consider three possible scenarios:

a.) Aaron’s email gets lost.

b.) Aaron’s email is received by Britney, but Britney’s confirmation email is lost.

c.) Aaron’s email is received by Britney, and Britney’s confirmation email is received by Aaron.

For each scenario:

i.) Does Britney know M?

ii.) What does Aaron know about what Britney knows about M?

iii.) Is M common knowledge?

Answer 1

a.) Aaron’s email gets lost.

(i) No

(ii) Aron thinks Britney knows about M but hasn’t confirmed yet

(iii) No

b.) Aaron’s email is received by Britney, but Britney’s confirmation email is lost.

(i) Yes

(ii) Aron thinks Britney knows about M but hasn’t confirmed yet

(iii) Yes

c.) Aaron’s email is received by Britney, and Britney’s confirmation email is received by Aaron.

(i) Yes

(ii) Aron thinks Britney knows about M but has confirmed and meeting is on

(iii) Yes