On a remote, mysterious island there are three types of people: Knights, who always tell the truth; Liars, who always lie and Spies, who may answer in any order that they think fit.

Lenny is visiting this island when he comes across three men. He knows that one of them is a knight, one is a liar and one is a spy. However, he doesn't know the exact identities of the three men.

Lenny is permitted to ask these three gentlemen precisely two yes-no questions. All the three men will answer each question, one at a time, with either a "yes" or "no" response.

How does Lenny determine the true types of these three men?

*** Try avoiding extraneous questions like "Is the sun shining?" or, "Is the earth flat?"

Edited on February 13, 2022, 4:18 pm

Posted by Kenny M on 2022-02-13 14:59:59