There is a land where every inhabitant is either a day-knight or a night-knight. Day-knights tell the truth in the day and lie at night. Night-knights lie in the day and tell the truth at night.

There are two inhabitants A and B, one of whose name is Santos and the name of the other is Shane.
It is known that, Shane is a day knight and Santos is a night knight.

A says that B is Shane.

Is it day or night?

(In reply to re: Solution by Ady TZIDON)

Perhaps you misread what I wrote.

Saying "the other person is Shane" is equivalent to saying "I am a night-knight."  I haven't said anything about whether or not the person is lying. 

We already know that Shane is a day-night and Santos is a night-knight, so if someone says, "the other person is Shane," they are also saying, "I am Santos," and equivalently saying, "I am a night-knight."

So the puzzle is effectively reduced to this:

There is a land where every inhabitant is either a day-knight or a night-knight. Day-knights tell the truth in the day and lie at night. Night-knights lie in the day and tell the truth at night.

An inhabitant says, "I am a night-knight."

Is it day or night?

Posted by tomarken on 2014-05-02 12:24:18