Assignment 9

  1. Ex. 13.1 all parts.
  2. Ex. 13.4
  3. Ex. 13.5 (a)
  4. In the handout on Common Knowledge, there is the assertion on page 110 that common knowledge satisfies (K3) as well. Show this first for models with a finite number of worlds, then try to do this if the finiteness restriction is removed.