# Knights and Knaves Puzzle - Solution

### The Puzzle:

There are three people (Alex, Brook and Cody), one of whom is a knight, one a knave, and one a spy.

The knight always tells the truth, the knave always lies, and the spy can either lie or tell the truth.

Alex says: "Cody is a knave."

Brook says: "Alex is a knight."

Cody says: "I am the spy."

Who is the knight, who the knave, and who the spy?

The knight always tells the truth, the knave always lies, and the spy can either lie or tell the truth.

Alex says: "Cody is a knave."

Brook says: "Alex is a knight."

Cody says: "I am the spy."

Who is the knight, who the knave, and who the spy?

### Our Solution:

Alex is a Knight

Brook is a Spy

Cody is a Knave

Brook is not the knight, since if he is, then Alex would also be the knight.

Cody is not the knight, since his statement would then be a lie.

Therefore Alex is the knight. Hence Cody is the knave, and Brook is the spy.

Brook is a Spy

Cody is a Knave

Brook is not the knight, since if he is, then Alex would also be the knight.

Cody is not the knight, since his statement would then be a lie.

Therefore Alex is the knight. Hence Cody is the knave, and Brook is the spy.

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