Yes. If they personally didn't want it, they'd say "no". As they're uncertain about the others, they say they don't know. Then the final person knows the other

Yes. If they personally didn't want it, they'd say "no". As they're uncertain about the others, they say they don't know. Then the final person knows the others all want yes, and personally wants yes, so says yes. It's like lazy evaluation of booleans in if statements.