CS 404: Journal --- Week 4

1. Now Pocatello wants a College of Engineering! Suppose the following signs are put up:

   Moscow:

   The College of Engineering is not here.

   Boise:

   The College of Engineering is here.

   Pocatello:

   The College of Engineering is not in Boise.

   If exactly one of the signs is true, where is the College of Engineering?
2. Here are some more knights and knaves puzzles. Hint: Associate identifiers as follows. To represent that X is a knight, use the identifier x. If X says a statement S, then you can represent that as x = S since if x then X is a knight and tells the truth, and if - x, X is a knave and lies.
   1. Someone asks B "are you a knight?" to which B replies, "If I am a knight, I'll eat my hat." Prove that B has to eat a hat.
   2. B says of C, "If C is a knight, then I am a knave." What are B and C?